diff --git a/.php_cs.dist b/.php_cs.dist
index 620c6ee2db..48e57c7899 100644
--- a/.php_cs.dist
+++ b/.php_cs.dist
@@ -12,6 +12,10 @@ return PhpCsFixer\Config::create()
         'php_unit_no_expectation_annotation' => false, // part of `PHPUnitXYMigration:risky` ruleset, to be enabled when PHPUnit 4.x support will be dropped, as we don't want to rewrite exceptions handling twice
         'array_syntax' => array('syntax' => 'long'),
         'protected_to_private' => false,
+        // TODO remove the disabling once https://github.com/FriendsOfPHP/PHP-CS-Fixer/pull/3876 is merged and released
+        'native_constant_invocation' => false,
+        // Part of @Symfony:risky in PHP-CS-Fixer 2.13.0. To be removed from the config file once upgrading
+        'native_function_invocation' => array('include' => array('@compiler_optimized'), 'scope' => 'namespaced'),
     ))
     ->setRiskyAllowed(true)
     ->setFinder(
@@ -26,12 +30,17 @@ return PhpCsFixer\Config::create()
                 'Symfony/Component/Routing/Tests/Fixtures/dumper',
                 // fixture templates
                 'Symfony/Component/Templating/Tests/Fixtures/templates',
+                'Symfony/Bundle/FrameworkBundle/Tests/Fixtures/TemplatePathsCache',
                 'Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/Resources/Custom',
                 // generated fixtures
                 'Symfony/Component/VarDumper/Tests/Fixtures',
                 // resource templates
                 'Symfony/Bundle/FrameworkBundle/Resources/views/Form',
+                // explicit trigger_error tests
+                'Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/',
             ))
+            // Support for older PHPunit version
+            ->notPath('Symfony/Bridge/PhpUnit/SymfonyTestsListener.php')
             // file content autogenerated by `var_export`
             ->notPath('Symfony/Component/Translation/Tests/fixtures/resources.php')
             // test template
@@ -39,8 +48,6 @@ return PhpCsFixer\Config::create()
             // explicit heredoc test
             ->notPath('Symfony/Bundle/FrameworkBundle/Tests/Fixtures/Resources/views/translation.html.php')
             // explicit trigger_error tests
-            ->notPath('Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/default.phpt')
-            ->notPath('Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/weak.phpt')
             ->notPath('Symfony/Component/Debug/Tests/DebugClassLoaderTest.php')
             // invalid annotations on purpose
             ->notPath('Symfony/Component/DependencyInjection/Tests/Fixtures/includes/autowiring_classes.php')
diff --git a/src/Symfony/Bridge/Doctrine/ContainerAwareEventManager.php b/src/Symfony/Bridge/Doctrine/ContainerAwareEventManager.php
index 9ba6912e0f..20aaae85a1 100644
--- a/src/Symfony/Bridge/Doctrine/ContainerAwareEventManager.php
+++ b/src/Symfony/Bridge/Doctrine/ContainerAwareEventManager.php
@@ -54,7 +54,7 @@ class ContainerAwareEventManager extends EventManager
             $initialized = isset($this->initialized[$eventName]);
 
             foreach ($this->listeners[$eventName] as $hash => $listener) {
-                if (!$initialized && is_string($listener)) {
+                if (!$initialized && \is_string($listener)) {
                     $this->listeners[$eventName][$hash] = $listener = $this->container->get($listener);
                 }
 
@@ -98,7 +98,7 @@ class ContainerAwareEventManager extends EventManager
      */
     public function addEventListener($events, $listener)
     {
-        if (is_string($listener)) {
+        if (\is_string($listener)) {
             if ($this->initialized) {
                 throw new \RuntimeException('Adding lazy-loading listeners after construction is not supported.');
             }
@@ -124,7 +124,7 @@ class ContainerAwareEventManager extends EventManager
      */
     public function removeEventListener($events, $listener)
     {
-        if (is_string($listener)) {
+        if (\is_string($listener)) {
             $hash = '_service_'.$listener;
         } else {
             // Picks the hash code related to that listener
diff --git a/src/Symfony/Bridge/Doctrine/DataCollector/DoctrineDataCollector.php b/src/Symfony/Bridge/Doctrine/DataCollector/DoctrineDataCollector.php
index dae5d43f36..0b1434a71e 100644
--- a/src/Symfony/Bridge/Doctrine/DataCollector/DoctrineDataCollector.php
+++ b/src/Symfony/Bridge/Doctrine/DataCollector/DoctrineDataCollector.php
@@ -134,14 +134,14 @@ class DoctrineDataCollector extends DataCollector
         if (null === $query['params']) {
             $query['params'] = array();
         }
-        if (!is_array($query['params'])) {
+        if (!\is_array($query['params'])) {
             $query['params'] = array($query['params']);
         }
         foreach ($query['params'] as $j => $param) {
             if (isset($query['types'][$j])) {
                 // Transform the param according to the type
                 $type = $query['types'][$j];
-                if (is_string($type)) {
+                if (\is_string($type)) {
                     $type = Type::getType($type);
                 }
                 if ($type instanceof Type) {
@@ -168,15 +168,15 @@ class DoctrineDataCollector extends DataCollector
      */
     private function sanitizeParam($var): array
     {
-        if (is_object($var)) {
-            $className = get_class($var);
+        if (\is_object($var)) {
+            $className = \get_class($var);
 
             return method_exists($var, '__toString') ?
                 array(sprintf('/* Object(%s): */"%s"', $className, $var->__toString()), false) :
                 array(sprintf('/* Object(%s) */', $className), false);
         }
 
-        if (is_array($var)) {
+        if (\is_array($var)) {
             $a = array();
             $original = true;
             foreach ($var as $k => $v) {
@@ -188,7 +188,7 @@ class DoctrineDataCollector extends DataCollector
             return array($a, $original);
         }
 
-        if (is_resource($var)) {
+        if (\is_resource($var)) {
             return array(sprintf('/* Resource(%s) */', get_resource_type($var)), false);
         }
 
diff --git a/src/Symfony/Bridge/Doctrine/DependencyInjection/AbstractDoctrineExtension.php b/src/Symfony/Bridge/Doctrine/DependencyInjection/AbstractDoctrineExtension.php
index 2850ab47cd..8ae09d32ef 100644
--- a/src/Symfony/Bridge/Doctrine/DependencyInjection/AbstractDoctrineExtension.php
+++ b/src/Symfony/Bridge/Doctrine/DependencyInjection/AbstractDoctrineExtension.php
@@ -141,7 +141,7 @@ abstract class AbstractDoctrineExtension extends Extension
      */
     protected function getMappingDriverBundleConfigDefaults(array $bundleConfig, \ReflectionClass $bundle, ContainerBuilder $container)
     {
-        $bundleDir = dirname($bundle->getFileName());
+        $bundleDir = \dirname($bundle->getFileName());
 
         if (!$bundleConfig['type']) {
             $bundleConfig['type'] = $this->detectMetadataDriver($bundleDir, $container);
@@ -153,7 +153,7 @@ abstract class AbstractDoctrineExtension extends Extension
         }
 
         if (!$bundleConfig['dir']) {
-            if (in_array($bundleConfig['type'], array('annotation', 'staticphp'))) {
+            if (\in_array($bundleConfig['type'], array('annotation', 'staticphp'))) {
                 $bundleConfig['dir'] = $bundleDir.'/'.$this->getMappingObjectDefaultName();
             } else {
                 $bundleConfig['dir'] = $bundleDir.'/'.$this->getMappingResourceConfigDirectory();
@@ -240,7 +240,7 @@ abstract class AbstractDoctrineExtension extends Extension
             throw new \InvalidArgumentException(sprintf('Specified non-existing directory "%s" as Doctrine mapping source.', $mappingConfig['dir']));
         }
 
-        if (!in_array($mappingConfig['type'], array('xml', 'yml', 'annotation', 'php', 'staticphp'))) {
+        if (!\in_array($mappingConfig['type'], array('xml', 'yml', 'annotation', 'php', 'staticphp'))) {
             throw new \InvalidArgumentException(sprintf('Can only configure "xml", "yml", "annotation", "php" or '.
                 '"staticphp" through the DoctrineBundle. Use your own bundle to configure other metadata drivers. '.
                 'You can register them by adding a new driver to the '.
@@ -272,7 +272,7 @@ abstract class AbstractDoctrineExtension extends Extension
             // add the closest existing directory as a resource
             $resource = $dir.'/'.$configPath;
             while (!is_dir($resource)) {
-                $resource = dirname($resource);
+                $resource = \dirname($resource);
             }
             $container->fileExists($resource, false);
 
diff --git a/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/DoctrineValidationPass.php b/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/DoctrineValidationPass.php
index 5f74ecfbcc..17f5be39bd 100644
--- a/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/DoctrineValidationPass.php
+++ b/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/DoctrineValidationPass.php
@@ -52,7 +52,7 @@ class DoctrineValidationPass implements CompilerPassInterface
 
         foreach ($container->getParameter('kernel.bundles') as $bundle) {
             $reflection = new \ReflectionClass($bundle);
-            if ($container->fileExists($file = dirname($reflection->getFileName()).'/'.$validationPath)) {
+            if ($container->fileExists($file = \dirname($reflection->getFileName()).'/'.$validationPath)) {
                 $files[] = $file;
             }
         }
diff --git a/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterEventListenersAndSubscribersPass.php b/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterEventListenersAndSubscribersPass.php
index 0753f5f09c..c26a2f84ff 100644
--- a/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterEventListenersAndSubscribersPass.php
+++ b/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterEventListenersAndSubscribersPass.php
@@ -146,7 +146,7 @@ class RegisterEventListenersAndSubscribersPass implements CompilerPassInterface
 
         if ($sortedTags) {
             krsort($sortedTags);
-            $sortedTags = call_user_func_array('array_merge', $sortedTags);
+            $sortedTags = \call_user_func_array('array_merge', $sortedTags);
         }
 
         return $sortedTags;
diff --git a/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterMappingsPass.php b/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterMappingsPass.php
index 4f140f81ed..73cd2dc06c 100644
--- a/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterMappingsPass.php
+++ b/src/Symfony/Bridge/Doctrine/DependencyInjection/CompilerPass/RegisterMappingsPass.php
@@ -124,7 +124,7 @@ abstract class RegisterMappingsPass implements CompilerPassInterface
         $this->managerParameters = $managerParameters;
         $this->driverPattern = $driverPattern;
         $this->enabledParameter = $enabledParameter;
-        if (count($aliasMap) && (!$configurationPattern || !$registerAliasMethodName)) {
+        if (\count($aliasMap) && (!$configurationPattern || !$registerAliasMethodName)) {
             throw new \InvalidArgumentException('configurationPattern and registerAliasMethodName are required to register namespace alias');
         }
         $this->configurationPattern = $configurationPattern;
@@ -149,7 +149,7 @@ abstract class RegisterMappingsPass implements CompilerPassInterface
             $chainDriverDef->addMethodCall('addDriver', array($mappingDriverDef, $namespace));
         }
 
-        if (!count($this->aliasMap)) {
+        if (!\count($this->aliasMap)) {
             return;
         }
 
diff --git a/src/Symfony/Bridge/Doctrine/Form/ChoiceList/DoctrineChoiceLoader.php b/src/Symfony/Bridge/Doctrine/Form/ChoiceList/DoctrineChoiceLoader.php
index a5a08b13ea..7df0c37a4e 100644
--- a/src/Symfony/Bridge/Doctrine/Form/ChoiceList/DoctrineChoiceLoader.php
+++ b/src/Symfony/Bridge/Doctrine/Form/ChoiceList/DoctrineChoiceLoader.php
@@ -83,7 +83,7 @@ class DoctrineChoiceLoader implements ChoiceLoaderInterface
 
         // Optimize performance for single-field identifiers. We already
         // know that the IDs are used as values
-        $optimize = null === $value || is_array($value) && $value[0] === $this->idReader;
+        $optimize = null === $value || \is_array($value) && $value[0] === $this->idReader;
 
         // Attention: This optimization does not check choices for existence
         if ($optimize && !$this->choiceList && $this->idReader->isSingleId()) {
@@ -120,7 +120,7 @@ class DoctrineChoiceLoader implements ChoiceLoaderInterface
 
         // Optimize performance in case we have an object loader and
         // a single-field identifier
-        $optimize = null === $value || is_array($value) && $this->idReader === $value[0];
+        $optimize = null === $value || \is_array($value) && $this->idReader === $value[0];
 
         if ($optimize && !$this->choiceList && $this->objectLoader && $this->idReader->isSingleId()) {
             $unorderedObjects = $this->objectLoader->getEntitiesByIds($this->idReader->getIdField(), $values);
diff --git a/src/Symfony/Bridge/Doctrine/Form/ChoiceList/IdReader.php b/src/Symfony/Bridge/Doctrine/Form/ChoiceList/IdReader.php
index 3f3a5c8ac4..381d02fcbe 100644
--- a/src/Symfony/Bridge/Doctrine/Form/ChoiceList/IdReader.php
+++ b/src/Symfony/Bridge/Doctrine/Form/ChoiceList/IdReader.php
@@ -42,8 +42,8 @@ class IdReader
 
         $this->om = $om;
         $this->classMetadata = $classMetadata;
-        $this->singleId = 1 === count($ids);
-        $this->intId = $this->singleId && in_array($idType, array('integer', 'smallint', 'bigint'));
+        $this->singleId = 1 === \count($ids);
+        $this->intId = $this->singleId && \in_array($idType, array('integer', 'smallint', 'bigint'));
         $this->idField = current($ids);
 
         // single field association are resolved, since the schema column could be an int
@@ -95,7 +95,7 @@ class IdReader
         }
 
         if (!$this->om->contains($object)) {
-            throw new RuntimeException(sprintf('Entity of type "%s" passed to the choice field must be managed. Maybe you forget to persist it in the entity manager?', get_class($object)));
+            throw new RuntimeException(sprintf('Entity of type "%s" passed to the choice field must be managed. Maybe you forget to persist it in the entity manager?', \get_class($object)));
         }
 
         $this->om->initializeObject($object);
diff --git a/src/Symfony/Bridge/Doctrine/Form/ChoiceList/ORMQueryBuilderLoader.php b/src/Symfony/Bridge/Doctrine/Form/ChoiceList/ORMQueryBuilderLoader.php
index 540fd0e031..5481eb872e 100644
--- a/src/Symfony/Bridge/Doctrine/Form/ChoiceList/ORMQueryBuilderLoader.php
+++ b/src/Symfony/Bridge/Doctrine/Form/ChoiceList/ORMQueryBuilderLoader.php
@@ -64,7 +64,7 @@ class ORMQueryBuilderLoader implements EntityLoaderInterface
         // Guess type
         $entity = current($qb->getRootEntities());
         $metadata = $qb->getEntityManager()->getClassMetadata($entity);
-        if (in_array($metadata->getTypeOfField($identifier), array('integer', 'bigint', 'smallint'))) {
+        if (\in_array($metadata->getTypeOfField($identifier), array('integer', 'bigint', 'smallint'))) {
             $parameterType = Connection::PARAM_INT_ARRAY;
 
             // Filter out non-integer values (e.g. ""). If we don't, some
@@ -72,7 +72,7 @@ class ORMQueryBuilderLoader implements EntityLoaderInterface
             $values = array_values(array_filter($values, function ($v) {
                 return (string) $v === (string) (int) $v || ctype_digit($v);
             }));
-        } elseif (in_array($metadata->getTypeOfField($identifier), array('uuid', 'guid'))) {
+        } elseif (\in_array($metadata->getTypeOfField($identifier), array('uuid', 'guid'))) {
             $parameterType = Connection::PARAM_STR_ARRAY;
 
             // Like above, but we just filter out empty strings.
diff --git a/src/Symfony/Bridge/Doctrine/Form/DataTransformer/CollectionToArrayTransformer.php b/src/Symfony/Bridge/Doctrine/Form/DataTransformer/CollectionToArrayTransformer.php
index 307361a52a..63c8f2439b 100644
--- a/src/Symfony/Bridge/Doctrine/Form/DataTransformer/CollectionToArrayTransformer.php
+++ b/src/Symfony/Bridge/Doctrine/Form/DataTransformer/CollectionToArrayTransformer.php
@@ -36,7 +36,7 @@ class CollectionToArrayTransformer implements DataTransformerInterface
 
         // For cases when the collection getter returns $collection->toArray()
         // in order to prevent modifications of the returned collection
-        if (is_array($collection)) {
+        if (\is_array($collection)) {
             return $collection;
         }
 
diff --git a/src/Symfony/Bridge/Doctrine/Form/DoctrineOrmTypeGuesser.php b/src/Symfony/Bridge/Doctrine/Form/DoctrineOrmTypeGuesser.php
index 9ed6027379..2194e2d5e7 100644
--- a/src/Symfony/Bridge/Doctrine/Form/DoctrineOrmTypeGuesser.php
+++ b/src/Symfony/Bridge/Doctrine/Form/DoctrineOrmTypeGuesser.php
@@ -140,7 +140,7 @@ class DoctrineOrmTypeGuesser implements FormTypeGuesserInterface
                 return new ValueGuess($mapping['length'], Guess::HIGH_CONFIDENCE);
             }
 
-            if (in_array($ret[0]->getTypeOfField($property), array(Type::DECIMAL, Type::FLOAT))) {
+            if (\in_array($ret[0]->getTypeOfField($property), array(Type::DECIMAL, Type::FLOAT))) {
                 return new ValueGuess(null, Guess::MEDIUM_CONFIDENCE);
             }
         }
@@ -153,7 +153,7 @@ class DoctrineOrmTypeGuesser implements FormTypeGuesserInterface
     {
         $ret = $this->getMetadata($class);
         if ($ret && isset($ret[0]->fieldMappings[$property]) && !$ret[0]->hasAssociation($property)) {
-            if (in_array($ret[0]->getTypeOfField($property), array(Type::DECIMAL, Type::FLOAT))) {
+            if (\in_array($ret[0]->getTypeOfField($property), array(Type::DECIMAL, Type::FLOAT))) {
                 return new ValueGuess(null, Guess::MEDIUM_CONFIDENCE);
             }
         }
diff --git a/src/Symfony/Bridge/Doctrine/Form/EventListener/MergeDoctrineCollectionListener.php b/src/Symfony/Bridge/Doctrine/Form/EventListener/MergeDoctrineCollectionListener.php
index 487523dd5d..17e645d5d6 100644
--- a/src/Symfony/Bridge/Doctrine/Form/EventListener/MergeDoctrineCollectionListener.php
+++ b/src/Symfony/Bridge/Doctrine/Form/EventListener/MergeDoctrineCollectionListener.php
@@ -45,7 +45,7 @@ class MergeDoctrineCollectionListener implements EventSubscriberInterface
 
         // If all items were removed, call clear which has a higher
         // performance on persistent collections
-        if ($collection instanceof Collection && 0 === count($data)) {
+        if ($collection instanceof Collection && 0 === \count($data)) {
             $collection->clear();
         }
     }
diff --git a/src/Symfony/Bridge/Doctrine/Form/Type/DoctrineType.php b/src/Symfony/Bridge/Doctrine/Form/Type/DoctrineType.php
index 547a70adab..666ad25fc3 100644
--- a/src/Symfony/Bridge/Doctrine/Form/Type/DoctrineType.php
+++ b/src/Symfony/Bridge/Doctrine/Form/Type/DoctrineType.php
@@ -216,8 +216,8 @@ abstract class DoctrineType extends AbstractType implements ResetInterface
         // Invoke the query builder closure so that we can cache choice lists
         // for equal query builders
         $queryBuilderNormalizer = function (Options $options, $queryBuilder) {
-            if (is_callable($queryBuilder)) {
-                $queryBuilder = call_user_func($queryBuilder, $options['em']->getRepository($options['class']));
+            if (\is_callable($queryBuilder)) {
+                $queryBuilder = \call_user_func($queryBuilder, $options['em']->getRepository($options['class']));
             }
 
             return $queryBuilder;
diff --git a/src/Symfony/Bridge/Doctrine/Form/Type/EntityType.php b/src/Symfony/Bridge/Doctrine/Form/Type/EntityType.php
index 4b07e83652..fa4176ee18 100644
--- a/src/Symfony/Bridge/Doctrine/Form/Type/EntityType.php
+++ b/src/Symfony/Bridge/Doctrine/Form/Type/EntityType.php
@@ -28,8 +28,8 @@ class EntityType extends DoctrineType
         // Invoke the query builder closure so that we can cache choice lists
         // for equal query builders
         $queryBuilderNormalizer = function (Options $options, $queryBuilder) {
-            if (is_callable($queryBuilder)) {
-                $queryBuilder = call_user_func($queryBuilder, $options['em']->getRepository($options['class']));
+            if (\is_callable($queryBuilder)) {
+                $queryBuilder = \call_user_func($queryBuilder, $options['em']->getRepository($options['class']));
 
                 if (null !== $queryBuilder && !$queryBuilder instanceof QueryBuilder) {
                     throw new UnexpectedTypeException($queryBuilder, 'Doctrine\ORM\QueryBuilder');
diff --git a/src/Symfony/Bridge/Doctrine/Logger/DbalLogger.php b/src/Symfony/Bridge/Doctrine/Logger/DbalLogger.php
index 42574edcad..9099fe0676 100644
--- a/src/Symfony/Bridge/Doctrine/Logger/DbalLogger.php
+++ b/src/Symfony/Bridge/Doctrine/Logger/DbalLogger.php
@@ -71,12 +71,12 @@ class DbalLogger implements SQLLogger
     {
         foreach ($params as $index => $param) {
             // normalize recursively
-            if (is_array($param)) {
+            if (\is_array($param)) {
                 $params[$index] = $this->normalizeParams($param);
                 continue;
             }
 
-            if (!is_string($params[$index])) {
+            if (!\is_string($params[$index])) {
                 continue;
             }
 
diff --git a/src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php b/src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php
index ea2793d471..324b02ea58 100644
--- a/src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php
+++ b/src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php
@@ -51,7 +51,7 @@ class EntityUserProvider implements UserProviderInterface
             $user = $repository->findOneBy(array($this->property => $username));
         } else {
             if (!$repository instanceof UserLoaderInterface) {
-                throw new \InvalidArgumentException(sprintf('You must either make the "%s" entity Doctrine Repository ("%s") implement "Symfony\Bridge\Doctrine\Security\User\UserLoaderInterface" or set the "property" option in the corresponding entity provider configuration.', $this->classOrAlias, get_class($repository)));
+                throw new \InvalidArgumentException(sprintf('You must either make the "%s" entity Doctrine Repository ("%s") implement "Symfony\Bridge\Doctrine\Security\User\UserLoaderInterface" or set the "property" option in the corresponding entity provider configuration.', $this->classOrAlias, \get_class($repository)));
             }
 
             $user = $repository->loadUserByUsername($username);
@@ -71,7 +71,7 @@ class EntityUserProvider implements UserProviderInterface
     {
         $class = $this->getClass();
         if (!$user instanceof $class) {
-            throw new UnsupportedUserException(sprintf('Instances of "%s" are not supported.', get_class($user)));
+            throw new UnsupportedUserException(sprintf('Instances of "%s" are not supported.', \get_class($user)));
         }
 
         $repository = $this->getRepository();
diff --git a/src/Symfony/Bridge/Doctrine/Test/DoctrineTestHelper.php b/src/Symfony/Bridge/Doctrine/Test/DoctrineTestHelper.php
index ee1e36859e..2b555d87b1 100644
--- a/src/Symfony/Bridge/Doctrine/Test/DoctrineTestHelper.php
+++ b/src/Symfony/Bridge/Doctrine/Test/DoctrineTestHelper.php
@@ -34,7 +34,7 @@ class DoctrineTestHelper
      */
     public static function createTestEntityManager(Configuration $config = null)
     {
-        if (!extension_loaded('pdo_sqlite')) {
+        if (!\extension_loaded('pdo_sqlite')) {
             TestCase::markTestSkipped('Extension pdo_sqlite is required.');
         }
 
diff --git a/src/Symfony/Bridge/Doctrine/Tests/DependencyInjection/DoctrineExtensionTest.php b/src/Symfony/Bridge/Doctrine/Tests/DependencyInjection/DoctrineExtensionTest.php
index 9770e031a1..039cb6aaf2 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/DependencyInjection/DoctrineExtensionTest.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/DependencyInjection/DoctrineExtensionTest.php
@@ -68,7 +68,7 @@ class DoctrineExtensionTest extends TestCase
             'SecondBundle' => 'My\SecondBundle',
         );
 
-        $reflection = new \ReflectionClass(get_class($this->extension));
+        $reflection = new \ReflectionClass(\get_class($this->extension));
         $method = $reflection->getMethod('fixManagersAutoMappings');
         $method->setAccessible(true);
 
@@ -157,7 +157,7 @@ class DoctrineExtensionTest extends TestCase
             'SecondBundle' => 'My\SecondBundle',
         );
 
-        $reflection = new \ReflectionClass(get_class($this->extension));
+        $reflection = new \ReflectionClass(\get_class($this->extension));
         $method = $reflection->getMethod('fixManagersAutoMappings');
         $method->setAccessible(true);
 
diff --git a/src/Symfony/Bridge/Doctrine/Tests/Form/Type/EntityTypePerformanceTest.php b/src/Symfony/Bridge/Doctrine/Tests/Form/Type/EntityTypePerformanceTest.php
index ac96ea21c5..048747c937 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/Form/Type/EntityTypePerformanceTest.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/Form/Type/EntityTypePerformanceTest.php
@@ -72,7 +72,7 @@ class EntityTypePerformanceTest extends FormPerformanceTestCase
         $ids = range(1, 300);
 
         foreach ($ids as $id) {
-            $name = 65 + (int) chr($id % 57);
+            $name = 65 + (int) \chr($id % 57);
             $this->em->persist(new SingleIntIdEntity($id, $name));
         }
 
diff --git a/src/Symfony/Bridge/Doctrine/Tests/Logger/DbalLoggerTest.php b/src/Symfony/Bridge/Doctrine/Tests/Logger/DbalLoggerTest.php
index 1e3e6ca6ec..38bbed1294 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/Logger/DbalLoggerTest.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/Logger/DbalLoggerTest.php
@@ -145,7 +145,7 @@ class DbalLoggerTest extends TestCase
         ;
 
         $testStringArray = array('é', 'á', 'ű', 'ő', 'ú', 'ö', 'ü', 'ó', 'í');
-        $testStringCount = count($testStringArray);
+        $testStringCount = \count($testStringArray);
 
         $shortString = '';
         $longString = '';
diff --git a/src/Symfony/Bridge/Doctrine/Tests/PropertyInfo/Fixtures/DoctrineFooType.php b/src/Symfony/Bridge/Doctrine/Tests/PropertyInfo/Fixtures/DoctrineFooType.php
index 394eaebdef..8d0a938114 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/PropertyInfo/Fixtures/DoctrineFooType.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/PropertyInfo/Fixtures/DoctrineFooType.php
@@ -50,7 +50,7 @@ class DoctrineFooType extends Type
             return;
         }
         if (!$value instanceof Foo) {
-            throw new ConversionException(sprintf('Expected %s, got %s', 'Symfony\Bridge\Doctrine\Tests\PropertyInfo\Fixtures\Foo', gettype($value)));
+            throw new ConversionException(sprintf('Expected %s, got %s', 'Symfony\Bridge\Doctrine\Tests\PropertyInfo\Fixtures\Foo', \gettype($value)));
         }
 
         return $foo->bar;
@@ -64,7 +64,7 @@ class DoctrineFooType extends Type
         if (null === $value) {
             return;
         }
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw ConversionException::conversionFailed($value, self::NAME);
         }
 
diff --git a/src/Symfony/Bridge/Doctrine/Tests/Security/User/EntityUserProviderTest.php b/src/Symfony/Bridge/Doctrine/Tests/Security/User/EntityUserProviderTest.php
index 78a2cdb6f3..45568a626a 100644
--- a/src/Symfony/Bridge/Doctrine/Tests/Security/User/EntityUserProviderTest.php
+++ b/src/Symfony/Bridge/Doctrine/Tests/Security/User/EntityUserProviderTest.php
@@ -146,7 +146,7 @@ class EntityUserProviderTest extends TestCase
         $provider = new EntityUserProvider($this->getManager($em), 'Symfony\Bridge\Doctrine\Tests\Fixtures\User', 'name');
 
         $user2 = $em->getReference('Symfony\Bridge\Doctrine\Tests\Fixtures\User', array('id1' => 1, 'id2' => 1));
-        $this->assertTrue($provider->supportsClass(get_class($user2)));
+        $this->assertTrue($provider->supportsClass(\get_class($user2)));
     }
 
     public function testLoadUserByUserNameShouldLoadUserWhenProperInterfaceProvided()
diff --git a/src/Symfony/Bridge/Doctrine/Validator/Constraints/UniqueEntityValidator.php b/src/Symfony/Bridge/Doctrine/Validator/Constraints/UniqueEntityValidator.php
index 004de6f67e..230b52fd56 100644
--- a/src/Symfony/Bridge/Doctrine/Validator/Constraints/UniqueEntityValidator.php
+++ b/src/Symfony/Bridge/Doctrine/Validator/Constraints/UniqueEntityValidator.php
@@ -46,17 +46,17 @@ class UniqueEntityValidator extends ConstraintValidator
             throw new UnexpectedTypeException($constraint, __NAMESPACE__.'\UniqueEntity');
         }
 
-        if (!is_array($constraint->fields) && !is_string($constraint->fields)) {
+        if (!\is_array($constraint->fields) && !\is_string($constraint->fields)) {
             throw new UnexpectedTypeException($constraint->fields, 'array');
         }
 
-        if (null !== $constraint->errorPath && !is_string($constraint->errorPath)) {
+        if (null !== $constraint->errorPath && !\is_string($constraint->errorPath)) {
             throw new UnexpectedTypeException($constraint->errorPath, 'string or null');
         }
 
         $fields = (array) $constraint->fields;
 
-        if (0 === count($fields)) {
+        if (0 === \count($fields)) {
             throw new ConstraintDefinitionException('At least one field has to be specified.');
         }
 
@@ -71,14 +71,14 @@ class UniqueEntityValidator extends ConstraintValidator
                 throw new ConstraintDefinitionException(sprintf('Object manager "%s" does not exist.', $constraint->em));
             }
         } else {
-            $em = $this->registry->getManagerForClass(get_class($entity));
+            $em = $this->registry->getManagerForClass(\get_class($entity));
 
             if (!$em) {
-                throw new ConstraintDefinitionException(sprintf('Unable to find the object manager associated with an entity of class "%s".', get_class($entity)));
+                throw new ConstraintDefinitionException(sprintf('Unable to find the object manager associated with an entity of class "%s".', \get_class($entity)));
             }
         }
 
-        $class = $em->getClassMetadata(get_class($entity));
+        $class = $em->getClassMetadata(\get_class($entity));
         /* @var $class \Doctrine\Common\Persistence\Mapping\ClassMetadata */
 
         $criteria = array();
@@ -133,7 +133,7 @@ class UniqueEntityValidator extends ConstraintValidator
                 throw new ConstraintDefinitionException(sprintf('The "%s" entity repository does not support the "%s" entity. The entity should be an instance of or extend "%s".', $constraint->entityClass, $class->getName(), $supportedClass));
             }
         } else {
-            $repository = $em->getRepository(get_class($entity));
+            $repository = $em->getRepository(\get_class($entity));
         }
 
         $result = $repository->{$constraint->repositoryMethod}($criteria);
@@ -182,11 +182,11 @@ class UniqueEntityValidator extends ConstraintValidator
 
     private function formatWithIdentifiers(ObjectManager $em, ClassMetadata $class, $value)
     {
-        if (!is_object($value) || $value instanceof \DateTimeInterface) {
+        if (!\is_object($value) || $value instanceof \DateTimeInterface) {
             return $this->formatValue($value, self::PRETTY_DATE);
         }
 
-        if ($class->getName() !== $idClass = get_class($value)) {
+        if ($class->getName() !== $idClass = \get_class($value)) {
             // non unique value might be a composite PK that consists of other entity objects
             if ($em->getMetadataFactory()->hasMetadataFor($idClass)) {
                 $identifiers = $em->getClassMetadata($idClass)->getIdentifierValues($value);
@@ -204,10 +204,10 @@ class UniqueEntityValidator extends ConstraintValidator
         }
 
         array_walk($identifiers, function (&$id, $field) {
-            if (!is_object($id) || $id instanceof \DateTimeInterface) {
+            if (!\is_object($id) || $id instanceof \DateTimeInterface) {
                 $idAsString = $this->formatValue($id, self::PRETTY_DATE);
             } else {
-                $idAsString = sprintf('object("%s")', get_class($id));
+                $idAsString = sprintf('object("%s")', \get_class($id));
             }
 
             $id = sprintf('%s => %s', $field, $idAsString);
diff --git a/src/Symfony/Bridge/Doctrine/Validator/DoctrineInitializer.php b/src/Symfony/Bridge/Doctrine/Validator/DoctrineInitializer.php
index 42cafdd129..010c051581 100644
--- a/src/Symfony/Bridge/Doctrine/Validator/DoctrineInitializer.php
+++ b/src/Symfony/Bridge/Doctrine/Validator/DoctrineInitializer.php
@@ -30,7 +30,7 @@ class DoctrineInitializer implements ObjectInitializerInterface
 
     public function initialize($object)
     {
-        $manager = $this->registry->getManagerForClass(get_class($object));
+        $manager = $this->registry->getManagerForClass(\get_class($object));
         if (null !== $manager) {
             $manager->initializeObject($object);
         }
diff --git a/src/Symfony/Bridge/Monolog/Handler/FingersCrossed/HttpCodeActivationStrategy.php b/src/Symfony/Bridge/Monolog/Handler/FingersCrossed/HttpCodeActivationStrategy.php
index 561af6f394..a97168e3a6 100644
--- a/src/Symfony/Bridge/Monolog/Handler/FingersCrossed/HttpCodeActivationStrategy.php
+++ b/src/Symfony/Bridge/Monolog/Handler/FingersCrossed/HttpCodeActivationStrategy.php
@@ -61,7 +61,7 @@ class HttpCodeActivationStrategy extends ErrorLevelActivationStrategy
                 }
 
                 $urlBlacklist = null;
-                if (count($exclusion['urls'])) {
+                if (\count($exclusion['urls'])) {
                     return !preg_match('{('.implode('|', $exclusion['urls']).')}i', $request->getPathInfo());
                 }
 
diff --git a/src/Symfony/Bridge/Monolog/Handler/ServerLogHandler.php b/src/Symfony/Bridge/Monolog/Handler/ServerLogHandler.php
index 99979c5a80..6c21a335f0 100644
--- a/src/Symfony/Bridge/Monolog/Handler/ServerLogHandler.php
+++ b/src/Symfony/Bridge/Monolog/Handler/ServerLogHandler.php
@@ -102,7 +102,7 @@ class ServerLogHandler extends AbstractHandler
     {
         if ($this->processors) {
             foreach ($this->processors as $processor) {
-                $record = call_user_func($processor, $record);
+                $record = \call_user_func($processor, $record);
             }
         }
 
diff --git a/src/Symfony/Bridge/PhpUnit/ClockMock.php b/src/Symfony/Bridge/PhpUnit/ClockMock.php
index 40ed8ecc0e..9ab2c779b3 100644
--- a/src/Symfony/Bridge/PhpUnit/ClockMock.php
+++ b/src/Symfony/Bridge/PhpUnit/ClockMock.php
@@ -71,7 +71,7 @@ class ClockMock
 
     public static function register($class)
     {
-        $self = get_called_class();
+        $self = \get_called_class();
 
         $mockedNs = array(substr($class, 0, strrpos($class, '\\')));
         if (0 < strpos($class, '\\Tests\\')) {
@@ -81,7 +81,7 @@ class ClockMock
             $mockedNs[] = substr($class, 6, strrpos($class, '\\') - 6);
         }
         foreach ($mockedNs as $ns) {
-            if (function_exists($ns.'\time')) {
+            if (\function_exists($ns.'\time')) {
                 continue;
             }
             eval(<<<EOPHP
diff --git a/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php b/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php
index 2836d9136d..7086c834b1 100644
--- a/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php
+++ b/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php
@@ -68,7 +68,7 @@ class DeprecationErrorHandler
                 foreach (get_declared_classes() as $class) {
                     if ('C' === $class[0] && 0 === strpos($class, 'ComposerAutoloaderInit')) {
                         $r = new \ReflectionClass($class);
-                        $v = dirname(dirname($r->getFileName()));
+                        $v = \dirname(\dirname($r->getFileName()));
                         if (file_exists($v.'/composer/installed.json')) {
                             $vendors[] = $v;
                         }
@@ -80,7 +80,7 @@ class DeprecationErrorHandler
                 return true;
             }
             foreach ($vendors as $vendor) {
-                if (0 === strpos($realPath, $vendor) && false !== strpbrk(substr($realPath, strlen($vendor), 1), '/'.\DIRECTORY_SEPARATOR)) {
+                if (0 === strpos($realPath, $vendor) && false !== strpbrk(substr($realPath, \strlen($vendor), 1), '/'.\DIRECTORY_SEPARATOR)) {
                     return true;
                 }
             }
@@ -112,7 +112,7 @@ class DeprecationErrorHandler
             $group = 'other';
             $isVendor = DeprecationErrorHandler::MODE_WEAK_VENDORS === $mode && $inVendors($file);
 
-            $i = count($trace);
+            $i = \count($trace);
             while (1 < $i && (!isset($trace[--$i]['class']) || ('ReflectionMethod' === $trace[$i]['class'] || 0 === strpos($trace[$i]['class'], 'PHPUnit_') || 0 === strpos($trace[$i]['class'], 'PHPUnit\\')))) {
                 // No-op
             }
@@ -129,7 +129,7 @@ class DeprecationErrorHandler
                     // if the error has been triggered from vendor code.
                     $isVendor = DeprecationErrorHandler::MODE_WEAK_VENDORS === $mode && isset($parsedMsg['triggering_file']) && $inVendors($parsedMsg['triggering_file']);
                 } else {
-                    $class = isset($trace[$i]['object']) ? get_class($trace[$i]['object']) : $trace[$i]['class'];
+                    $class = isset($trace[$i]['object']) ? \get_class($trace[$i]['object']) : $trace[$i]['class'];
                     $method = $trace[$i]['function'];
                 }
 
@@ -141,7 +141,7 @@ class DeprecationErrorHandler
                     || 0 === strpos($method, 'provideLegacy')
                     || 0 === strpos($method, 'getLegacy')
                     || strpos($class, '\Legacy')
-                    || in_array('legacy', $Test::getGroups($class, $method), true)
+                    || \in_array('legacy', $Test::getGroups($class, $method), true)
                 ) {
                     $group = 'legacy';
                 } elseif ($isVendor) {
@@ -154,7 +154,7 @@ class DeprecationErrorHandler
                     $e = new \Exception($msg);
                     $r = new \ReflectionProperty($e, 'trace');
                     $r->setAccessible(true);
-                    $r->setValue($e, array_slice($trace, 1, $i));
+                    $r->setValue($e, \array_slice($trace, 1, $i));
 
                     echo "\n".ucfirst($group).' deprecation triggered by '.$class.'::'.$method.':';
                     echo "\n".$msg;
@@ -255,12 +255,12 @@ class DeprecationErrorHandler
 
                 // reset deprecations array
                 foreach ($deprecations as $group => $arrayOrInt) {
-                    $deprecations[$group] = is_int($arrayOrInt) ? 0 : array();
+                    $deprecations[$group] = \is_int($arrayOrInt) ? 0 : array();
                 }
 
                 register_shutdown_function(function () use (&$deprecations, $isFailing, $displayDeprecations, $mode) {
                     foreach ($deprecations as $group => $arrayOrInt) {
-                        if (0 < (is_int($arrayOrInt) ? $arrayOrInt : count($arrayOrInt))) {
+                        if (0 < (\is_int($arrayOrInt) ? $arrayOrInt : \count($arrayOrInt))) {
                             echo "Shutdown-time deprecations:\n";
                             break;
                         }
@@ -307,7 +307,7 @@ class DeprecationErrorHandler
      */
     private static function hasColorSupport()
     {
-        if (!defined('STDOUT')) {
+        if (!\defined('STDOUT')) {
             return false;
         }
 
@@ -316,18 +316,18 @@ class DeprecationErrorHandler
         }
 
         if (\DIRECTORY_SEPARATOR === '\\') {
-            return (function_exists('sapi_windows_vt100_support')
+            return (\function_exists('sapi_windows_vt100_support')
                 && sapi_windows_vt100_support(STDOUT))
                 || false !== getenv('ANSICON')
                 || 'ON' === getenv('ConEmuANSI')
                 || 'xterm' === getenv('TERM');
         }
 
-        if (function_exists('stream_isatty')) {
+        if (\function_exists('stream_isatty')) {
             return stream_isatty(STDOUT);
         }
 
-        if (function_exists('posix_isatty')) {
+        if (\function_exists('posix_isatty')) {
             return posix_isatty(STDOUT);
         }
 
diff --git a/src/Symfony/Bridge/PhpUnit/DnsMock.php b/src/Symfony/Bridge/PhpUnit/DnsMock.php
index a85ec977c7..790cfa91af 100644
--- a/src/Symfony/Bridge/PhpUnit/DnsMock.php
+++ b/src/Symfony/Bridge/PhpUnit/DnsMock.php
@@ -163,7 +163,7 @@ class DnsMock
 
     public static function register($class)
     {
-        $self = get_called_class();
+        $self = \get_called_class();
 
         $mockedNs = array(substr($class, 0, strrpos($class, '\\')));
         if (0 < strpos($class, '\\Tests\\')) {
@@ -173,7 +173,7 @@ class DnsMock
             $mockedNs[] = substr($class, 6, strrpos($class, '\\') - 6);
         }
         foreach ($mockedNs as $ns) {
-            if (function_exists($ns.'\checkdnsrr')) {
+            if (\function_exists($ns.'\checkdnsrr')) {
                 continue;
             }
             eval(<<<EOPHP
diff --git a/src/Symfony/Bridge/PhpUnit/Legacy/CoverageListenerTrait.php b/src/Symfony/Bridge/PhpUnit/Legacy/CoverageListenerTrait.php
index ab1cda6702..8e9bdbe92e 100644
--- a/src/Symfony/Bridge/PhpUnit/Legacy/CoverageListenerTrait.php
+++ b/src/Symfony/Bridge/PhpUnit/Legacy/CoverageListenerTrait.php
@@ -58,7 +58,7 @@ class CoverageListenerTrait
                 if (method_exists($test->getTestResultObject(), 'addWarning') && class_exists(Warning::class)) {
                     $test->getTestResultObject()->addWarning($test, new Warning($message), 0);
                 } else {
-                    $this->warnings[] = sprintf("%s::%s\n%s", get_class($test), $test->getName(), $message);
+                    $this->warnings[] = sprintf("%s::%s\n%s", \get_class($test), $test->getName(), $message);
                 }
             }
 
@@ -75,7 +75,7 @@ class CoverageListenerTrait
 
         $cache = $r->getValue();
         $cache = array_replace_recursive($cache, array(
-            get_class($test) => array(
+            \get_class($test) => array(
                 'covers' => array($sutFqcn),
             ),
         ));
@@ -90,7 +90,7 @@ class CoverageListenerTrait
             return $resolver($test);
         }
 
-        $class = get_class($test);
+        $class = \get_class($test);
 
         $sutFqcn = str_replace('\\Tests\\', '\\', $class);
         $sutFqcn = preg_replace('{Test$}', '', $sutFqcn);
diff --git a/src/Symfony/Bridge/PhpUnit/Legacy/SymfonyTestsListenerTrait.php b/src/Symfony/Bridge/PhpUnit/Legacy/SymfonyTestsListenerTrait.php
index 7ded32a782..d072e7e91f 100644
--- a/src/Symfony/Bridge/PhpUnit/Legacy/SymfonyTestsListenerTrait.php
+++ b/src/Symfony/Bridge/PhpUnit/Legacy/SymfonyTestsListenerTrait.php
@@ -53,7 +53,7 @@ class SymfonyTestsListenerTrait
         }
 
         foreach ($mockedNamespaces as $type => $namespaces) {
-            if (!is_array($namespaces)) {
+            if (!\is_array($namespaces)) {
                 $namespaces = array($namespaces);
             }
             if ('time-sensitive' === $type) {
@@ -98,10 +98,10 @@ class SymfonyTestsListenerTrait
         $this->testsWithWarnings = array();
 
         foreach ($suite->tests() as $test) {
-            if (!($test instanceof \PHPUnit_Framework_TestCase || $test instanceof TestCase)) {
+            if (!($test instanceof \PHPUnit\Framework\TestCase || $test instanceof TestCase)) {
                 continue;
             }
-            if (null === $Test::getPreserveGlobalStateSettings(get_class($test), $test->getName(false))) {
+            if (null === $Test::getPreserveGlobalStateSettings(\get_class($test), $test->getName(false))) {
                 $test->setPreserveGlobalState(false);
             }
         }
@@ -139,10 +139,10 @@ class SymfonyTestsListenerTrait
                             continue;
                         }
                         $groups = $Test::getGroups($test->getName());
-                        if (in_array('time-sensitive', $groups, true)) {
+                        if (\in_array('time-sensitive', $groups, true)) {
                             ClockMock::register($test->getName());
                         }
-                        if (in_array('dns-sensitive', $groups, true)) {
+                        if (\in_array('dns-sensitive', $groups, true)) {
                             DnsMock::register($test->getName());
                         }
                     }
@@ -151,7 +151,7 @@ class SymfonyTestsListenerTrait
         } elseif (2 === $this->state) {
             $skipped = array();
             foreach ($suite->tests() as $test) {
-                if (!($test instanceof \PHPUnit_Framework_TestCase || $test instanceof TestCase)
+                if (!($test instanceof \PHPUnit\Framework\TestCase || $test instanceof TestCase)
                     || isset($this->wasSkipped[$suiteName]['*'])
                     || isset($this->wasSkipped[$suiteName][$test->getName()])) {
                     $skipped[] = $test;
@@ -164,8 +164,8 @@ class SymfonyTestsListenerTrait
     public function addSkippedTest($test, \Exception $e, $time)
     {
         if (0 < $this->state) {
-            if ($test instanceof \PHPUnit_Framework_TestCase || $test instanceof TestCase) {
-                $class = get_class($test);
+            if ($test instanceof \PHPUnit\Framework\TestCase || $test instanceof TestCase) {
+                $class = \get_class($test);
                 $method = $test->getName();
             } else {
                 $class = $test->getName();
@@ -178,7 +178,7 @@ class SymfonyTestsListenerTrait
 
     public function startTest($test)
     {
-        if (-2 < $this->state && ($test instanceof \PHPUnit_Framework_TestCase || $test instanceof TestCase)) {
+        if (-2 < $this->state && ($test instanceof \PHPUnit\Framework\TestCase || $test instanceof TestCase)) {
             if (null !== $test->getTestResultObject()) {
                 $this->reportUselessTests = $test->getTestResultObject()->isStrictAboutTestsThatDoNotTestAnything();
             }
@@ -196,25 +196,25 @@ class SymfonyTestsListenerTrait
                 $Test = 'PHPUnit\Util\Test';
                 $AssertionFailedError = 'PHPUnit\Framework\AssertionFailedError';
             }
-            $groups = $Test::getGroups(get_class($test), $test->getName(false));
+            $groups = $Test::getGroups(\get_class($test), $test->getName(false));
 
             if (!$this->runsInSeparateProcess) {
-                if (in_array('time-sensitive', $groups, true)) {
-                    ClockMock::register(get_class($test));
+                if (\in_array('time-sensitive', $groups, true)) {
+                    ClockMock::register(\get_class($test));
                     ClockMock::withClockMock(true);
                 }
-                if (in_array('dns-sensitive', $groups, true)) {
-                    DnsMock::register(get_class($test));
+                if (\in_array('dns-sensitive', $groups, true)) {
+                    DnsMock::register(\get_class($test));
                 }
             }
 
-            $annotations = $Test::parseTestMethodAnnotations(get_class($test), $test->getName(false));
+            $annotations = $Test::parseTestMethodAnnotations(\get_class($test), $test->getName(false));
 
             if (isset($annotations['class']['expectedDeprecation'])) {
                 $test->getTestResultObject()->addError($test, new $AssertionFailedError('`@expectedDeprecation` annotations are not allowed at the class level.'), 0);
             }
             if (isset($annotations['method']['expectedDeprecation'])) {
-                if (!in_array('legacy', $groups, true)) {
+                if (!\in_array('legacy', $groups, true)) {
                     $this->error = new $AssertionFailedError('Only tests with the `@group legacy` annotation can have `@expectedDeprecation`.');
                 }
 
@@ -228,7 +228,7 @@ class SymfonyTestsListenerTrait
 
     public function addWarning($test, $e, $time)
     {
-        if ($test instanceof \PHPUnit_Framework_TestCase || $test instanceof TestCase) {
+        if ($test instanceof \PHPUnit\Framework\TestCase || $test instanceof TestCase) {
             $this->testsWithWarnings[$test->getName()] = true;
         }
     }
@@ -244,7 +244,7 @@ class SymfonyTestsListenerTrait
             $BaseTestRunner = 'PHPUnit\Runner\BaseTestRunner';
             $Warning = 'PHPUnit\Framework\Warning';
         }
-        $className = get_class($test);
+        $className = \get_class($test);
         $classGroups = $Test::getGroups($className);
         $groups = $Test::getGroups($className, $test->getName(false));
 
@@ -265,7 +265,7 @@ class SymfonyTestsListenerTrait
             foreach ($deprecations ? unserialize($deprecations) : array() as $deprecation) {
                 $error = serialize(array('deprecation' => $deprecation[1], 'class' => $className, 'method' => $test->getName(false), 'triggering_file' => isset($deprecation[2]) ? $deprecation[2] : null));
                 if ($deprecation[0]) {
-                    trigger_error($error, E_USER_DEPRECATED);
+                    @trigger_error($error, E_USER_DEPRECATED);
                 } else {
                     @trigger_error($error, E_USER_DEPRECATED);
                 }
@@ -274,13 +274,13 @@ class SymfonyTestsListenerTrait
         }
 
         if ($this->expectedDeprecations) {
-            if (!in_array($test->getStatus(), array($BaseTestRunner::STATUS_SKIPPED, $BaseTestRunner::STATUS_INCOMPLETE), true)) {
-                $test->addToAssertionCount(count($this->expectedDeprecations));
+            if (!\in_array($test->getStatus(), array($BaseTestRunner::STATUS_SKIPPED, $BaseTestRunner::STATUS_INCOMPLETE), true)) {
+                $test->addToAssertionCount(\count($this->expectedDeprecations));
             }
 
             restore_error_handler();
 
-            if (!$errored && !in_array($test->getStatus(), array($BaseTestRunner::STATUS_SKIPPED, $BaseTestRunner::STATUS_INCOMPLETE, $BaseTestRunner::STATUS_FAILURE, $BaseTestRunner::STATUS_ERROR), true)) {
+            if (!$errored && !\in_array($test->getStatus(), array($BaseTestRunner::STATUS_SKIPPED, $BaseTestRunner::STATUS_INCOMPLETE, $BaseTestRunner::STATUS_FAILURE, $BaseTestRunner::STATUS_ERROR), true)) {
                 try {
                     $prefix = "@expectedDeprecation:\n";
                     $test->assertStringMatchesFormat($prefix.'%A  '.implode("\n%A  ", $this->expectedDeprecations)."\n%A", $prefix.'  '.implode("\n  ", $this->gatheredDeprecations)."\n");
@@ -294,11 +294,11 @@ class SymfonyTestsListenerTrait
             $this->expectedDeprecations = $this->gatheredDeprecations = array();
             $this->previousErrorHandler = null;
         }
-        if (!$this->runsInSeparateProcess && -2 < $this->state && ($test instanceof \PHPUnit_Framework_TestCase || $test instanceof TestCase)) {
-            if (in_array('time-sensitive', $groups, true)) {
+        if (!$this->runsInSeparateProcess && -2 < $this->state && ($test instanceof \PHPUnit\Framework\TestCase || $test instanceof TestCase)) {
+            if (\in_array('time-sensitive', $groups, true)) {
                 ClockMock::withClockMock(false);
             }
-            if (in_array('dns-sensitive', $groups, true)) {
+            if (\in_array('dns-sensitive', $groups, true)) {
                 DnsMock::withMockedHosts(array());
             }
         }
@@ -314,7 +314,7 @@ class SymfonyTestsListenerTrait
         // If the message is serialized we need to extract the message. This occurs when the error is triggered by
         // by the isolated test path in \Symfony\Bridge\PhpUnit\Legacy\SymfonyTestsListenerTrait::endTest().
         $parsedMsg = @unserialize($msg);
-        if (is_array($parsedMsg)) {
+        if (\is_array($parsedMsg)) {
             $msg = $parsedMsg['deprecation'];
         }
         if (error_reporting()) {
diff --git a/src/Symfony/Bridge/ProxyManager/LazyProxy/PhpDumper/ProxyDumper.php b/src/Symfony/Bridge/ProxyManager/LazyProxy/PhpDumper/ProxyDumper.php
index b3234194bc..208639a4b1 100644
--- a/src/Symfony/Bridge/ProxyManager/LazyProxy/PhpDumper/ProxyDumper.php
+++ b/src/Symfony/Bridge/ProxyManager/LazyProxy/PhpDumper/ProxyDumper.php
@@ -103,7 +103,7 @@ EOF;
             return '0.0.1';
         }
 
-        return defined(Version::class.'::VERSION') ? Version::VERSION : Version::getVersion();
+        return \defined(Version::class.'::VERSION') ? Version::VERSION : Version::getVersion();
     }
 
     /**
diff --git a/src/Symfony/Bridge/ProxyManager/Tests/LazyProxy/PhpDumper/ProxyDumperTest.php b/src/Symfony/Bridge/ProxyManager/Tests/LazyProxy/PhpDumper/ProxyDumperTest.php
index 4d5702dc8d..b1dc1cf66a 100644
--- a/src/Symfony/Bridge/ProxyManager/Tests/LazyProxy/PhpDumper/ProxyDumperTest.php
+++ b/src/Symfony/Bridge/ProxyManager/Tests/LazyProxy/PhpDumper/ProxyDumperTest.php
@@ -13,7 +13,6 @@ namespace Symfony\Bridge\ProxyManager\Tests\LazyProxy\PhpDumper;
 
 use PHPUnit\Framework\TestCase;
 use Symfony\Bridge\ProxyManager\LazyProxy\PhpDumper\ProxyDumper;
-use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Definition;
 
 /**
diff --git a/src/Symfony/Bridge/Twig/AppVariable.php b/src/Symfony/Bridge/Twig/AppVariable.php
index 54a785c0a4..702edcbcea 100644
--- a/src/Symfony/Bridge/Twig/AppVariable.php
+++ b/src/Symfony/Bridge/Twig/AppVariable.php
@@ -83,7 +83,7 @@ class AppVariable
         }
 
         $user = $token->getUser();
-        if (is_object($user)) {
+        if (\is_object($user)) {
             return $user;
         }
     }
@@ -169,7 +169,7 @@ class AppVariable
             return $session->getFlashBag()->all();
         }
 
-        if (is_string($types)) {
+        if (\is_string($types)) {
             return $session->getFlashBag()->get($types);
         }
 
diff --git a/src/Symfony/Bridge/Twig/Command/DebugCommand.php b/src/Symfony/Bridge/Twig/Command/DebugCommand.php
index e8f67d1623..f00dac08b8 100644
--- a/src/Symfony/Bridge/Twig/Command/DebugCommand.php
+++ b/src/Symfony/Bridge/Twig/Command/DebugCommand.php
@@ -121,7 +121,7 @@ EOF
         $firstNamespace = true;
         $prevHasSeparator = false;
         foreach ($this->getLoaderPaths() as $namespace => $paths) {
-            if (!$firstNamespace && !$prevHasSeparator && count($paths) > 1) {
+            if (!$firstNamespace && !$prevHasSeparator && \count($paths) > 1) {
                 $rows[] = array('', '');
             }
             $firstNamespace = false;
@@ -129,7 +129,7 @@ EOF
                 $rows[] = array($namespace, $path.DIRECTORY_SEPARATOR);
                 $namespace = '';
             }
-            if (count($paths) > 1) {
+            if (\count($paths) > 1) {
                 $rows[] = array('', '');
                 $prevHasSeparator = true;
             } else {
@@ -159,7 +159,7 @@ EOF
         foreach ($loader->getNamespaces() as $namespace) {
             $paths = array_map(function ($path) {
                 if (null !== $this->projectDir && 0 === strpos($path, $this->projectDir)) {
-                    $path = ltrim(substr($path, strlen($this->projectDir)), DIRECTORY_SEPARATOR);
+                    $path = ltrim(substr($path, \strlen($this->projectDir)), DIRECTORY_SEPARATOR);
                 }
 
                 return $path;
@@ -190,16 +190,16 @@ EOF
             if (null === $cb) {
                 return;
             }
-            if (is_array($cb)) {
+            if (\is_array($cb)) {
                 if (!method_exists($cb[0], $cb[1])) {
                     return;
                 }
                 $refl = new \ReflectionMethod($cb[0], $cb[1]);
-            } elseif (is_object($cb) && method_exists($cb, '__invoke')) {
+            } elseif (\is_object($cb) && method_exists($cb, '__invoke')) {
                 $refl = new \ReflectionMethod($cb, '__invoke');
-            } elseif (function_exists($cb)) {
+            } elseif (\function_exists($cb)) {
                 $refl = new \ReflectionFunction($cb);
-            } elseif (is_string($cb) && preg_match('{^(.+)::(.+)$}', $cb, $m) && method_exists($m[1], $m[2])) {
+            } elseif (\is_string($cb) && preg_match('{^(.+)::(.+)$}', $cb, $m) && method_exists($m[1], $m[2])) {
                 $refl = new \ReflectionMethod($m[1], $m[2]);
             } else {
                 throw new \UnexpectedValueException('Unsupported callback type');
@@ -249,8 +249,8 @@ EOF
         }
 
         if ('globals' === $type) {
-            if (is_object($meta)) {
-                return ' = object('.get_class($meta).')';
+            if (\is_object($meta)) {
+                return ' = object('.\get_class($meta).')';
             }
 
             return ' = '.substr(@json_encode($meta), 0, 50);
diff --git a/src/Symfony/Bridge/Twig/Command/LintCommand.php b/src/Symfony/Bridge/Twig/Command/LintCommand.php
index 84a62ae933..68eebf123c 100644
--- a/src/Symfony/Bridge/Twig/Command/LintCommand.php
+++ b/src/Symfony/Bridge/Twig/Command/LintCommand.php
@@ -77,7 +77,7 @@ EOF
         $io = new SymfonyStyle($input, $output);
         $filenames = $input->getArgument('filename');
 
-        if (0 === count($filenames)) {
+        if (0 === \count($filenames)) {
             if (0 !== ftell(STDIN)) {
                 throw new RuntimeException('Please provide a filename or pipe template content to STDIN.');
             }
@@ -162,9 +162,9 @@ EOF
         }
 
         if (0 === $errors) {
-            $io->success(sprintf('All %d Twig files contain valid syntax.', count($filesInfo)));
+            $io->success(sprintf('All %d Twig files contain valid syntax.', \count($filesInfo)));
         } else {
-            $io->warning(sprintf('%d Twig files have valid syntax and %d contain errors.', count($filesInfo) - $errors, $errors));
+            $io->warning(sprintf('%d Twig files have valid syntax and %d contain errors.', \count($filesInfo) - $errors, $errors));
         }
 
         return min($errors, 1);
@@ -217,7 +217,7 @@ EOF
         $lines = explode("\n", $template);
 
         $position = max(0, $line - $context);
-        $max = min(count($lines), $line - 1 + $context);
+        $max = min(\count($lines), $line - 1 + $context);
 
         $result = array();
         while ($position < $max) {
diff --git a/src/Symfony/Bridge/Twig/Extension/CodeExtension.php b/src/Symfony/Bridge/Twig/Extension/CodeExtension.php
index f2885266d9..e158007c5c 100644
--- a/src/Symfony/Bridge/Twig/Extension/CodeExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/CodeExtension.php
@@ -35,7 +35,7 @@ class CodeExtension extends AbstractExtension
     public function __construct($fileLinkFormat, string $rootDir, string $charset, string $projectDir = null)
     {
         $this->fileLinkFormat = $fileLinkFormat ?: ini_get('xdebug.file_link_format') ?: get_cfg_var('xdebug.file_link_format');
-        $this->rootDir = str_replace('/', DIRECTORY_SEPARATOR, dirname($rootDir)).DIRECTORY_SEPARATOR;
+        $this->rootDir = str_replace('/', DIRECTORY_SEPARATOR, \dirname($rootDir)).DIRECTORY_SEPARATOR;
         $this->charset = $charset;
         $this->projectDir = $projectDir;
     }
@@ -97,7 +97,7 @@ class CodeExtension extends AbstractExtension
                 $short = array_pop($parts);
                 $formattedValue = sprintf('<em>object</em>(<abbr title="%s">%s</abbr>)', $item[1], $short);
             } elseif ('array' === $item[0]) {
-                $formattedValue = sprintf('<em>array</em>(%s)', is_array($item[1]) ? $this->formatArgs($item[1]) : $item[1]);
+                $formattedValue = sprintf('<em>array</em>(%s)', \is_array($item[1]) ? $this->formatArgs($item[1]) : $item[1]);
             } elseif ('null' === $item[0]) {
                 $formattedValue = '<em>null</em>';
             } elseif ('boolean' === $item[0]) {
@@ -108,7 +108,7 @@ class CodeExtension extends AbstractExtension
                 $formattedValue = str_replace("\n", '', htmlspecialchars(var_export($item[1], true), ENT_COMPAT | ENT_SUBSTITUTE, $this->charset));
             }
 
-            $result[] = is_int($key) ? $formattedValue : sprintf("'%s' => %s", $key, $formattedValue);
+            $result[] = \is_int($key) ? $formattedValue : sprintf("'%s' => %s", $key, $formattedValue);
         }
 
         return implode(', ', $result);
@@ -151,10 +151,10 @@ class CodeExtension extends AbstractExtension
 
             $lines = array();
             if (0 > $srcContext) {
-                $srcContext = count($content);
+                $srcContext = \count($content);
             }
 
-            for ($i = max($line - $srcContext, 1), $max = min($line + $srcContext, count($content)); $i <= $max; ++$i) {
+            for ($i = max($line - $srcContext, 1), $max = min($line + $srcContext, \count($content)); $i <= $max; ++$i) {
                 $lines[] = '<li'.($i == $line ? ' class="selected"' : '').'><a class="anchor" name="line'.$i.'"></a><code>'.self::fixCodeMarkup($content[$i - 1]).'</code></li>';
             }
 
@@ -178,7 +178,7 @@ class CodeExtension extends AbstractExtension
         if (null === $text) {
             $text = str_replace('/', DIRECTORY_SEPARATOR, $file);
             if (0 === strpos($text, $this->rootDir)) {
-                $text = substr($text, strlen($this->rootDir));
+                $text = substr($text, \strlen($this->rootDir));
                 $text = explode(DIRECTORY_SEPARATOR, $text, 2);
                 $text = sprintf('<abbr title="%s%2$s">%s</abbr>%s', $this->rootDir, $text[0], isset($text[1]) ? DIRECTORY_SEPARATOR.$text[1] : '');
             }
@@ -206,7 +206,7 @@ class CodeExtension extends AbstractExtension
     public function getFileLink($file, $line)
     {
         if ($fmt = $this->fileLinkFormat) {
-            return is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line);
+            return \is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line);
         }
 
         return false;
diff --git a/src/Symfony/Bridge/Twig/Extension/DumpExtension.php b/src/Symfony/Bridge/Twig/Extension/DumpExtension.php
index 2cc3f1a4b0..3d4c6841f2 100644
--- a/src/Symfony/Bridge/Twig/Extension/DumpExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/DumpExtension.php
@@ -58,7 +58,7 @@ class DumpExtension extends AbstractExtension
             return;
         }
 
-        if (2 === func_num_args()) {
+        if (2 === \func_num_args()) {
             $vars = array();
             foreach ($context as $key => $value) {
                 if (!$value instanceof Template) {
@@ -68,7 +68,7 @@ class DumpExtension extends AbstractExtension
 
             $vars = array($vars);
         } else {
-            $vars = func_get_args();
+            $vars = \func_get_args();
             unset($vars[0], $vars[1]);
         }
 
diff --git a/src/Symfony/Bridge/Twig/Extension/FormExtension.php b/src/Symfony/Bridge/Twig/Extension/FormExtension.php
index 197d3c2c8a..54f3b70bf1 100644
--- a/src/Symfony/Bridge/Twig/Extension/FormExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/FormExtension.php
@@ -101,8 +101,8 @@ class FormExtension extends AbstractExtension
  */
 function twig_is_selected_choice(ChoiceView $choice, $selectedValue)
 {
-    if (is_array($selectedValue)) {
-        return in_array($choice->value, $selectedValue, true);
+    if (\is_array($selectedValue)) {
+        return \in_array($choice->value, $selectedValue, true);
     }
 
     return $choice->value === $selectedValue;
diff --git a/src/Symfony/Bridge/Twig/Extension/HttpFoundationExtension.php b/src/Symfony/Bridge/Twig/Extension/HttpFoundationExtension.php
index 0dad40cfa0..1c1b47bb2b 100644
--- a/src/Symfony/Bridge/Twig/Extension/HttpFoundationExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/HttpFoundationExtension.php
@@ -97,7 +97,7 @@ class HttpFoundationExtension extends AbstractExtension
 
         if (!$path || '/' !== $path[0]) {
             $prefix = $request->getPathInfo();
-            $last = strlen($prefix) - 1;
+            $last = \strlen($prefix) - 1;
             if ($last !== $pos = strrpos($prefix, '/')) {
                 $prefix = substr($prefix, 0, $pos).'/';
             }
diff --git a/src/Symfony/Bridge/Twig/Extension/RoutingExtension.php b/src/Symfony/Bridge/Twig/Extension/RoutingExtension.php
index 57e8902dce..a23a62bb28 100644
--- a/src/Symfony/Bridge/Twig/Extension/RoutingExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/RoutingExtension.php
@@ -100,7 +100,7 @@ class RoutingExtension extends AbstractExtension
             $argsNode->hasNode(1) ? $argsNode->getNode(1) : null
         );
 
-        if (null === $paramsNode || $paramsNode instanceof ArrayExpression && count($paramsNode) <= 2 &&
+        if (null === $paramsNode || $paramsNode instanceof ArrayExpression && \count($paramsNode) <= 2 &&
             (!$paramsNode->hasNode(1) || $paramsNode->getNode(1) instanceof ConstantExpression)
         ) {
             return array('html');
diff --git a/src/Symfony/Bridge/Twig/Extension/YamlExtension.php b/src/Symfony/Bridge/Twig/Extension/YamlExtension.php
index 81f1d32446..88b29d7c23 100644
--- a/src/Symfony/Bridge/Twig/Extension/YamlExtension.php
+++ b/src/Symfony/Bridge/Twig/Extension/YamlExtension.php
@@ -42,7 +42,7 @@ class YamlExtension extends AbstractExtension
             $dumper = new YamlDumper();
         }
 
-        if (defined('Symfony\Component\Yaml\Yaml::DUMP_OBJECT')) {
+        if (\defined('Symfony\Component\Yaml\Yaml::DUMP_OBJECT')) {
             return $dumper->dump($input, $inline, 0, $dumpObjects);
         }
 
@@ -51,12 +51,12 @@ class YamlExtension extends AbstractExtension
 
     public function dump($value, $inline = 0, $dumpObjects = false)
     {
-        if (is_resource($value)) {
+        if (\is_resource($value)) {
             return '%Resource%';
         }
 
-        if (is_array($value) || is_object($value)) {
-            return '%'.gettype($value).'% '.$this->encode($value, $inline, $dumpObjects);
+        if (\is_array($value) || \is_object($value)) {
+            return '%'.\gettype($value).'% '.$this->encode($value, $inline, $dumpObjects);
         }
 
         return $this->encode($value, $inline, $dumpObjects);
diff --git a/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php b/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php
index 51abce7104..bf97e52ad3 100644
--- a/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php
+++ b/src/Symfony/Bridge/Twig/Form/TwigRendererEngine.php
@@ -98,7 +98,7 @@ class TwigRendererEngine extends AbstractRendererEngine
 
         // Check each theme whether it contains the searched block
         if (isset($this->themes[$cacheKey])) {
-            for ($i = count($this->themes[$cacheKey]) - 1; $i >= 0; --$i) {
+            for ($i = \count($this->themes[$cacheKey]) - 1; $i >= 0; --$i) {
                 $this->loadResourcesFromTheme($cacheKey, $this->themes[$cacheKey][$i]);
                 // CONTINUE LOADING (see doc comment)
             }
@@ -107,7 +107,7 @@ class TwigRendererEngine extends AbstractRendererEngine
         // Check the default themes once we reach the root view without success
         if (!$view->parent) {
             if (!isset($this->useDefaultThemes[$cacheKey]) || $this->useDefaultThemes[$cacheKey]) {
-                for ($i = count($this->defaultThemes) - 1; $i >= 0; --$i) {
+                for ($i = \count($this->defaultThemes) - 1; $i >= 0; --$i) {
                     $this->loadResourcesFromTheme($cacheKey, $this->defaultThemes[$i]);
                     // CONTINUE LOADING (see doc comment)
                 }
diff --git a/src/Symfony/Bridge/Twig/NodeVisitor/TranslationDefaultDomainNodeVisitor.php b/src/Symfony/Bridge/Twig/NodeVisitor/TranslationDefaultDomainNodeVisitor.php
index 1a60e67a2f..7b443ffe5f 100644
--- a/src/Symfony/Bridge/Twig/NodeVisitor/TranslationDefaultDomainNodeVisitor.php
+++ b/src/Symfony/Bridge/Twig/NodeVisitor/TranslationDefaultDomainNodeVisitor.php
@@ -64,7 +64,7 @@ class TranslationDefaultDomainNodeVisitor extends AbstractNodeVisitor
             return $node;
         }
 
-        if ($node instanceof FilterExpression && in_array($node->getNode('filter')->getAttribute('value'), array('trans', 'transchoice'))) {
+        if ($node instanceof FilterExpression && \in_array($node->getNode('filter')->getAttribute('value'), array('trans', 'transchoice'))) {
             $arguments = $node->getNode('arguments');
             $ind = 'trans' === $node->getNode('filter')->getAttribute('value') ? 1 : 2;
             if ($this->isNamedArguments($arguments)) {
@@ -119,7 +119,7 @@ class TranslationDefaultDomainNodeVisitor extends AbstractNodeVisitor
     private function isNamedArguments($arguments)
     {
         foreach ($arguments as $name => $node) {
-            if (!is_int($name)) {
+            if (!\is_int($name)) {
                 return true;
             }
         }
diff --git a/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php b/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php
index 77d522f523..26201b2904 100644
--- a/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Command/DebugCommandTest.php
@@ -64,7 +64,7 @@ TXT;
 
     private function createCommandTester(array $paths = array())
     {
-        $filesystemLoader = new FilesystemLoader(array(), dirname(__DIR__).'/Fixtures');
+        $filesystemLoader = new FilesystemLoader(array(), \dirname(__DIR__).'/Fixtures');
         foreach ($paths as $namespace => $relDirs) {
             foreach ($relDirs as $relDir) {
                 $filesystemLoader->addPath($relDir, $namespace);
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php b/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php
index ce80418c83..e195641c09 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/DumpExtensionTest.php
@@ -76,7 +76,7 @@ class DumpExtensionTest extends TestCase
         array_unshift($args, $context);
         array_unshift($args, $twig);
 
-        $dump = call_user_func_array(array($extension, 'dump'), $args);
+        $dump = \call_user_func_array(array($extension, 'dump'), $args);
 
         if ($debug) {
             $this->assertStringStartsWith('<script>', $dump);
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/StopwatchExtensionTest.php b/src/Symfony/Bridge/Twig/Tests/Extension/StopwatchExtensionTest.php
index 25b2e029ee..901425b1b9 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/StopwatchExtensionTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/StopwatchExtensionTest.php
@@ -56,7 +56,7 @@ class StopwatchExtensionTest extends TestCase
 
     protected function getStopwatch($events = array())
     {
-        $events = is_array($events) ? $events : array($events);
+        $events = \is_array($events) ? $events : array($events);
         $stopwatch = $this->getMockBuilder('Symfony\Component\Stopwatch\Stopwatch')->getMock();
 
         $i = -1;
diff --git a/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php b/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php
index 88a39b1ea9..4784d2e00d 100644
--- a/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Extension/TranslationExtensionTest.php
@@ -206,7 +206,7 @@ class TranslationExtensionTest extends TestCase
             $translator = new Translator('en');
         }
 
-        if (is_array($template)) {
+        if (\is_array($template)) {
             $loader = new TwigArrayLoader($template);
         } else {
             $loader = new TwigArrayLoader(array('index' => $template));
diff --git a/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php b/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php
index 013598a40b..50d447bfb8 100644
--- a/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php
+++ b/src/Symfony/Bridge/Twig/Tests/Translation/TwigExtractorTest.php
@@ -90,7 +90,7 @@ class TwigExtractorTest extends TestCase
             $extractor->extract($resources, new MessageCatalogue('en'));
         } catch (Error $e) {
             if (method_exists($e, 'getSourceContext')) {
-                $this->assertSame(dirname(__DIR__).strtr('/Fixtures/extractor/syntax_error.twig', '/', DIRECTORY_SEPARATOR), $e->getFile());
+                $this->assertSame(\dirname(__DIR__).strtr('/Fixtures/extractor/syntax_error.twig', '/', DIRECTORY_SEPARATOR), $e->getFile());
                 $this->assertSame(1, $e->getLine());
                 $this->assertSame('Unclosed "block".', $e->getMessage());
             } else {
diff --git a/src/Symfony/Bundle/FrameworkBundle/Client.php b/src/Symfony/Bundle/FrameworkBundle/Client.php
index bc76ce28f0..0ebc04dbcd 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Client.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Client.php
@@ -169,7 +169,7 @@ class Client extends BaseClient
         foreach (get_declared_classes() as $class) {
             if (0 === strpos($class, 'ComposerAutoloaderInit')) {
                 $r = new \ReflectionClass($class);
-                $file = dirname(dirname($r->getFileName())).'/autoload.php';
+                $file = \dirname(\dirname($r->getFileName())).'/autoload.php';
                 if (file_exists($file)) {
                     $requires .= "require_once '".str_replace("'", "\\'", $file)."';\n";
                 }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/AboutCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/AboutCommand.php
index b6860a24ec..930de24466 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/AboutCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/AboutCommand.php
@@ -70,7 +70,7 @@ EOT
             new TableSeparator(),
             array('<info>Kernel</>'),
             new TableSeparator(),
-            array('Type', get_class($kernel)),
+            array('Type', \get_class($kernel)),
             array('Name', $kernel->getName()),
             array('Environment', $kernel->getEnvironment()),
             array('Debug', $kernel->isDebug() ? 'true' : 'false'),
@@ -85,9 +85,9 @@ EOT
             array('Architecture', (PHP_INT_SIZE * 8).' bits'),
             array('Intl locale', class_exists('Locale', false) && \Locale::getDefault() ? \Locale::getDefault() : 'n/a'),
             array('Timezone', date_default_timezone_get().' (<comment>'.(new \DateTime())->format(\DateTime::W3C).'</>)'),
-            array('OPcache', extension_loaded('Zend OPcache') && ini_get('opcache.enable') ? 'true' : 'false'),
-            array('APCu', extension_loaded('apcu') && ini_get('apc.enabled') ? 'true' : 'false'),
-            array('Xdebug', extension_loaded('xdebug') ? 'true' : 'false'),
+            array('OPcache', \extension_loaded('Zend OPcache') && ini_get('opcache.enable') ? 'true' : 'false'),
+            array('APCu', \extension_loaded('apcu') && ini_get('apc.enabled') ? 'true' : 'false'),
+            array('Xdebug', \extension_loaded('xdebug') ? 'true' : 'false'),
         );
 
         if ($dotenv = self::getDotenvVars()) {
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/AbstractConfigCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/AbstractConfigCommand.php
index edd3e64556..6d8960cd03 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/AbstractConfigCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/AbstractConfigCommand.php
@@ -109,7 +109,7 @@ abstract class AbstractConfigCommand extends ContainerDebugCommand
         }
 
         if (!$configuration instanceof ConfigurationInterface) {
-            throw new \LogicException(sprintf('Configuration class "%s" should implement ConfigurationInterface in order to be dumpable', get_class($configuration)));
+            throw new \LogicException(sprintf('Configuration class "%s" should implement ConfigurationInterface in order to be dumpable', \get_class($configuration)));
         }
     }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php
index 78bea75d37..58719fc2d9 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/AssetsInstallCommand.php
@@ -228,8 +228,8 @@ EOT
     private function symlink(string $originDir, string $targetDir, bool $relative = false)
     {
         if ($relative) {
-            $this->filesystem->mkdir(dirname($targetDir));
-            $originDir = $this->filesystem->makePathRelative($originDir, realpath(dirname($targetDir)));
+            $this->filesystem->mkdir(\dirname($targetDir));
+            $originDir = $this->filesystem->makePathRelative($originDir, realpath(\dirname($targetDir)));
         }
         $this->filesystem->symlink($originDir, $targetDir);
         if (!file_exists($targetDir)) {
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php
index 2127d5fbe9..2bf608904d 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php
@@ -95,7 +95,7 @@ EOF
         $this->getApplication()->setDispatcher(new EventDispatcher());
 
         $containerFile = (new \ReflectionObject($kernel->getContainer()))->getFileName();
-        $containerDir = basename(dirname($containerFile));
+        $containerDir = basename(\dirname($containerFile));
 
         // the warmup cache dir name must have the same length as the real one
         // to avoid the many problems in serialized resources files
@@ -136,7 +136,7 @@ EOF
 
             if ('/' === \DIRECTORY_SEPARATOR && $mounts = @file('/proc/mounts')) {
                 foreach ($mounts as $mount) {
-                    $mount = array_slice(explode(' ', $mount), 1, -3);
+                    $mount = \array_slice(explode(' ', $mount), 1, -3);
                     if (!\in_array(array_pop($mount), array('vboxsf', 'nfs'))) {
                         continue;
                     }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/ContainerDebugCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/ContainerDebugCommand.php
index e7ca1d5335..1bd0d1679f 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/ContainerDebugCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/ContainerDebugCommand.php
@@ -197,7 +197,7 @@ EOF
         $kernel = $this->getApplication()->getKernel();
 
         if (!$kernel->isDebug() || !(new ConfigCache($kernel->getContainer()->getParameter('debug.container.dump'), true))->isFresh()) {
-            $buildContainer = \Closure::bind(function () { return $this->buildContainer(); }, $kernel, get_class($kernel));
+            $buildContainer = \Closure::bind(function () { return $this->buildContainer(); }, $kernel, \get_class($kernel));
             $container = $buildContainer();
             $container->getCompilerPassConfig()->setRemovingPasses(array());
             $container->compile();
@@ -219,7 +219,7 @@ EOF
             throw new InvalidArgumentException(sprintf('No services found that match "%s".', $name));
         }
 
-        $default = 1 === count($matchingServices) ? $matchingServices[0] : null;
+        $default = 1 === \count($matchingServices) ? $matchingServices[0] : null;
 
         return $io->choice('Select one of the following services to display its information', $matchingServices, $default);
     }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/RouterDebugCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/RouterDebugCommand.php
index e4cec8d309..0d06e24976 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/RouterDebugCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/RouterDebugCommand.php
@@ -79,7 +79,7 @@ EOF
 
         if ($name) {
             if (!($route = $routes->get($name)) && $matchingRoutes = $this->findRouteNameContaining($name, $routes)) {
-                $default = 1 === count($matchingRoutes) ? $matchingRoutes[0] : null;
+                $default = 1 === \count($matchingRoutes) ? $matchingRoutes[0] : null;
                 $name = $io->choice('Select one of the matching routes', $matchingRoutes, $default);
                 $route = $routes->get($name);
             }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php
index 225269d7f1..d24885f35d 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationDebugCommand.php
@@ -219,8 +219,8 @@ EOF
                     $states[] = self::MESSAGE_UNUSED;
                 }
 
-                if (!in_array(self::MESSAGE_UNUSED, $states) && true === $input->getOption('only-unused')
-                    || !in_array(self::MESSAGE_MISSING, $states) && true === $input->getOption('only-missing')) {
+                if (!\in_array(self::MESSAGE_UNUSED, $states) && true === $input->getOption('only-unused')
+                    || !\in_array(self::MESSAGE_MISSING, $states) && true === $input->getOption('only-missing')) {
                     continue;
                 }
 
@@ -284,7 +284,7 @@ EOF
             if (mb_strlen($string, $encoding) > $length) {
                 return mb_substr($string, 0, $length - 3, $encoding).'...';
             }
-        } elseif (strlen($string) > $length) {
+        } elseif (\strlen($string) > $length) {
             return substr($string, 0, $length - 3).'...';
         }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
index 3322d32309..70e5f596f6 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/TranslationUpdateCommand.php
@@ -111,7 +111,7 @@ EOF
 
         // check format
         $supportedFormats = $this->writer->getFormats();
-        if (!in_array($input->getOption('output-format'), $supportedFormats)) {
+        if (!\in_array($input->getOption('output-format'), $supportedFormats)) {
             $errorIo->error(array('Wrong output format', 'Supported formats are: '.implode(', ', $supportedFormats).'.'));
 
             return 1;
@@ -190,7 +190,7 @@ EOF
             : new MergeOperation($currentCatalogue, $extractedCatalogue);
 
         // Exit if no messages found.
-        if (!count($operation->getDomains())) {
+        if (!\count($operation->getDomains())) {
             $errorIo->warning('No translation messages were found.');
 
             return;
@@ -216,7 +216,7 @@ EOF
                     }, array_keys($operation->getObsoleteMessages($domain)))
                 );
 
-                $domainMessagesCount = count($list);
+                $domainMessagesCount = \count($list);
 
                 $io->section(sprintf('Messages extracted for domain "<info>%s</info>" (%d message%s)', $domain, $domainMessagesCount, $domainMessagesCount > 1 ? 's' : ''));
                 $io->listing($list);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php
index 7161a18cec..07f27563a2 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/Descriptor.php
@@ -72,11 +72,11 @@ abstract class Descriptor implements DescriptorInterface
             case $object instanceof EventDispatcherInterface:
                 $this->describeEventDispatcherListeners($object, $options);
                 break;
-            case is_callable($object):
+            case \is_callable($object):
                 $this->describeCallable($object, $options);
                 break;
             default:
-                throw new \InvalidArgumentException(sprintf('Object of type "%s" is not describable.', get_class($object)));
+                throw new \InvalidArgumentException(sprintf('Object of type "%s" is not describable.', \get_class($object)));
         }
     }
 
@@ -181,11 +181,11 @@ abstract class Descriptor implements DescriptorInterface
      */
     protected function formatValue($value)
     {
-        if (is_object($value)) {
-            return sprintf('object(%s)', get_class($value));
+        if (\is_object($value)) {
+            return sprintf('object(%s)', \get_class($value));
         }
 
-        if (is_string($value)) {
+        if (\is_string($value)) {
             return $value;
         }
 
@@ -201,7 +201,7 @@ abstract class Descriptor implements DescriptorInterface
      */
     protected function formatParameter($value)
     {
-        if (is_bool($value) || is_array($value) || (null === $value)) {
+        if (\is_bool($value) || \is_array($value) || (null === $value)) {
             $jsonString = json_encode($value);
 
             if (preg_match('/^(.{60})./us', $jsonString, $matches)) {
diff --git a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/JsonDescriptor.php b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/JsonDescriptor.php
index 90747f4fd8..4bc8cafc41 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/JsonDescriptor.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/JsonDescriptor.php
@@ -90,7 +90,7 @@ class JsonDescriptor extends Descriptor
         } elseif ($service instanceof Definition) {
             $this->writeData($this->getContainerDefinitionData($service, isset($options['omit_tags']) && $options['omit_tags'], isset($options['show_arguments']) && $options['show_arguments']), $options);
         } else {
-            $this->writeData(get_class($service), $options);
+            $this->writeData(\get_class($service), $options);
         }
     }
 
@@ -121,7 +121,7 @@ class JsonDescriptor extends Descriptor
             } elseif ($service instanceof Definition) {
                 $data['definitions'][$serviceId] = $this->getContainerDefinitionData($service, $omitTags, $showArguments);
             } else {
-                $data['services'][$serviceId] = get_class($service);
+                $data['services'][$serviceId] = \get_class($service);
             }
         }
 
@@ -200,7 +200,7 @@ class JsonDescriptor extends Descriptor
             'hostRegex' => '' !== $route->getHost() ? $route->compile()->getHostRegex() : '',
             'scheme' => $route->getSchemes() ? implode('|', $route->getSchemes()) : 'ANY',
             'method' => $route->getMethods() ? implode('|', $route->getMethods()) : 'ANY',
-            'class' => get_class($route),
+            'class' => \get_class($route),
             'defaults' => $route->getDefaults(),
             'requirements' => $route->getRequirements() ?: 'NO CUSTOM',
             'options' => $route->getOptions(),
@@ -227,7 +227,7 @@ class JsonDescriptor extends Descriptor
         $data['file'] = $definition->getFile();
 
         if ($factory = $definition->getFactory()) {
-            if (is_array($factory)) {
+            if (\is_array($factory)) {
                 if ($factory[0] instanceof Reference) {
                     $data['factory_service'] = (string) $factory[0];
                 } elseif ($factory[0] instanceof Definition) {
@@ -242,7 +242,7 @@ class JsonDescriptor extends Descriptor
         }
 
         $calls = $definition->getMethodCalls();
-        if (count($calls) > 0) {
+        if (\count($calls) > 0) {
             $data['calls'] = array();
             foreach ($calls as $callData) {
                 $data['calls'][] = $callData[0];
@@ -299,12 +299,12 @@ class JsonDescriptor extends Descriptor
     {
         $data = array();
 
-        if (is_array($callable)) {
+        if (\is_array($callable)) {
             $data['type'] = 'function';
 
-            if (is_object($callable[0])) {
+            if (\is_object($callable[0])) {
                 $data['name'] = $callable[1];
-                $data['class'] = get_class($callable[0]);
+                $data['class'] = \get_class($callable[0]);
             } else {
                 if (0 !== strpos($callable[1], 'parent::')) {
                     $data['name'] = $callable[1];
@@ -321,7 +321,7 @@ class JsonDescriptor extends Descriptor
             return $data;
         }
 
-        if (is_string($callable)) {
+        if (\is_string($callable)) {
             $data['type'] = 'function';
 
             if (false === strpos($callable, '::')) {
@@ -345,7 +345,7 @@ class JsonDescriptor extends Descriptor
 
         if (method_exists($callable, '__invoke')) {
             $data['type'] = 'object';
-            $data['name'] = get_class($callable);
+            $data['name'] = \get_class($callable);
 
             return $data;
         }
@@ -355,7 +355,7 @@ class JsonDescriptor extends Descriptor
 
     private function describeValue($value, $omitTags, $showArguments)
     {
-        if (is_array($value)) {
+        if (\is_array($value)) {
             $data = array();
             foreach ($value as $k => $v) {
                 $data[$k] = $this->describeValue($v, $omitTags, $showArguments);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/MarkdownDescriptor.php b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/MarkdownDescriptor.php
index f96b684dc0..d14af62767 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/MarkdownDescriptor.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/MarkdownDescriptor.php
@@ -55,13 +55,13 @@ class MarkdownDescriptor extends Descriptor
             ."\n".'- Host Regex: '.('' !== $route->getHost() ? $route->compile()->getHostRegex() : '')
             ."\n".'- Scheme: '.($route->getSchemes() ? implode('|', $route->getSchemes()) : 'ANY')
             ."\n".'- Method: '.($route->getMethods() ? implode('|', $route->getMethods()) : 'ANY')
-            ."\n".'- Class: '.get_class($route)
+            ."\n".'- Class: '.\get_class($route)
             ."\n".'- Defaults: '.$this->formatRouterConfig($route->getDefaults())
             ."\n".'- Requirements: '.($route->getRequirements() ? $this->formatRouterConfig($route->getRequirements()) : 'NO CUSTOM')
             ."\n".'- Options: '.$this->formatRouterConfig($route->getOptions());
 
         $this->write(isset($options['name'])
-            ? $options['name']."\n".str_repeat('-', strlen($options['name']))."\n\n".$output
+            ? $options['name']."\n".str_repeat('-', \strlen($options['name']))."\n\n".$output
             : $output);
         $this->write("\n");
     }
@@ -86,7 +86,7 @@ class MarkdownDescriptor extends Descriptor
         $this->write("Container tags\n==============");
 
         foreach ($this->findDefinitionsByTag($builder, $showHidden) as $tag => $definitions) {
-            $this->write("\n\n".$tag."\n".str_repeat('-', strlen($tag)));
+            $this->write("\n\n".$tag."\n".str_repeat('-', \strlen($tag)));
             foreach ($definitions as $serviceId => $definition) {
                 $this->write("\n\n");
                 $this->describeContainerDefinition($definition, array('omit_tags' => true, 'id' => $serviceId));
@@ -110,7 +110,7 @@ class MarkdownDescriptor extends Descriptor
         } elseif ($service instanceof Definition) {
             $this->describeContainerDefinition($service, $childOptions);
         } else {
-            $this->write(sprintf('**`%s`:** `%s`', $options['id'], get_class($service)));
+            $this->write(sprintf('**`%s`:** `%s`', $options['id'], \get_class($service)));
         }
     }
 
@@ -125,7 +125,7 @@ class MarkdownDescriptor extends Descriptor
         if (isset($options['tag'])) {
             $title .= ' with tag `'.$options['tag'].'`';
         }
-        $this->write($title."\n".str_repeat('=', strlen($title)));
+        $this->write($title."\n".str_repeat('=', \strlen($title)));
 
         $serviceIds = isset($options['tag']) && $options['tag'] ? array_keys($builder->findTaggedServiceIds($options['tag'])) : $builder->getServiceIds();
         $showArguments = isset($options['show_arguments']) && $options['show_arguments'];
@@ -171,7 +171,7 @@ class MarkdownDescriptor extends Descriptor
             $this->write("\n\nServices\n--------\n");
             foreach ($services['services'] as $id => $service) {
                 $this->write("\n");
-                $this->write(sprintf('- `%s`: `%s`', $id, get_class($service)));
+                $this->write(sprintf('- `%s`: `%s`', $id, \get_class($service)));
             }
         }
     }
@@ -200,7 +200,7 @@ class MarkdownDescriptor extends Descriptor
         }
 
         if ($factory = $definition->getFactory()) {
-            if (is_array($factory)) {
+            if (\is_array($factory)) {
                 if ($factory[0] instanceof Reference) {
                     $output .= "\n".'- Factory Service: `'.$factory[0].'`';
                 } elseif ($factory[0] instanceof Definition) {
@@ -260,7 +260,7 @@ class MarkdownDescriptor extends Descriptor
      */
     protected function describeContainerParameter($parameter, array $options = array())
     {
-        $this->write(isset($options['parameter']) ? sprintf("%s\n%s\n\n%s", $options['parameter'], str_repeat('=', strlen($options['parameter'])), $this->formatParameter($parameter)) : $parameter);
+        $this->write(isset($options['parameter']) ? sprintf("%s\n%s\n\n%s", $options['parameter'], str_repeat('=', \strlen($options['parameter'])), $this->formatParameter($parameter)) : $parameter);
     }
 
     /**
@@ -306,12 +306,12 @@ class MarkdownDescriptor extends Descriptor
     {
         $string = '';
 
-        if (is_array($callable)) {
+        if (\is_array($callable)) {
             $string .= "\n- Type: `function`";
 
-            if (is_object($callable[0])) {
+            if (\is_object($callable[0])) {
                 $string .= "\n".sprintf('- Name: `%s`', $callable[1]);
-                $string .= "\n".sprintf('- Class: `%s`', get_class($callable[0]));
+                $string .= "\n".sprintf('- Class: `%s`', \get_class($callable[0]));
             } else {
                 if (0 !== strpos($callable[1], 'parent::')) {
                     $string .= "\n".sprintf('- Name: `%s`', $callable[1]);
@@ -328,7 +328,7 @@ class MarkdownDescriptor extends Descriptor
             return $this->write($string."\n");
         }
 
-        if (is_string($callable)) {
+        if (\is_string($callable)) {
             $string .= "\n- Type: `function`";
 
             if (false === strpos($callable, '::')) {
@@ -352,7 +352,7 @@ class MarkdownDescriptor extends Descriptor
 
         if (method_exists($callable, '__invoke')) {
             $string .= "\n- Type: `object`";
-            $string .= "\n".sprintf('- Name: `%s`', get_class($callable));
+            $string .= "\n".sprintf('- Name: `%s`', \get_class($callable));
 
             return $this->write($string."\n");
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/TextDescriptor.php b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/TextDescriptor.php
index 13b860ca28..b2dcc5f238 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/TextDescriptor.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/TextDescriptor.php
@@ -59,8 +59,8 @@ class TextDescriptor extends Descriptor
                 $controller = $route->getDefault('_controller');
                 if ($controller instanceof \Closure) {
                     $controller = 'Closure';
-                } elseif (is_object($controller)) {
-                    $controller = get_class($controller);
+                } elseif (\is_object($controller)) {
+                    $controller = \get_class($controller);
                 }
                 $row[] = $controller;
             }
@@ -92,7 +92,7 @@ class TextDescriptor extends Descriptor
             array('Scheme', ($route->getSchemes() ? implode('|', $route->getSchemes()) : 'ANY')),
             array('Method', ($route->getMethods() ? implode('|', $route->getMethods()) : 'ANY')),
             array('Requirements', ($route->getRequirements() ? $this->formatRouterConfig($route->getRequirements()) : 'NO CUSTOM')),
-            array('Class', get_class($route)),
+            array('Class', \get_class($route)),
             array('Defaults', $this->formatRouterConfig($route->getDefaults())),
             array('Options', $this->formatRouterConfig($route->getOptions())),
         );
@@ -155,7 +155,7 @@ class TextDescriptor extends Descriptor
             $options['output']->table(
                 array('Service ID', 'Class'),
                 array(
-                    array(isset($options['id']) ? $options['id'] : '-', get_class($service)),
+                    array(isset($options['id']) ? $options['id'] : '-', \get_class($service)),
                 )
             );
         }
@@ -203,10 +203,10 @@ class TextDescriptor extends Descriptor
                     foreach ($tags as $tag) {
                         foreach ($tag as $key => $value) {
                             if (!isset($maxTags[$key])) {
-                                $maxTags[$key] = strlen($key);
+                                $maxTags[$key] = \strlen($key);
                             }
-                            if (strlen($value) > $maxTags[$key]) {
-                                $maxTags[$key] = strlen($value);
+                            if (\strlen($value) > $maxTags[$key]) {
+                                $maxTags[$key] = \strlen($value);
                             }
                         }
                     }
@@ -214,7 +214,7 @@ class TextDescriptor extends Descriptor
             }
         }
 
-        $tagsCount = count($maxTags);
+        $tagsCount = \count($maxTags);
         $tagsNames = array_keys($maxTags);
 
         $tableHeaders = array_merge(array('Service ID'), $tagsNames, array('Class name'));
@@ -244,7 +244,7 @@ class TextDescriptor extends Descriptor
                 $alias = $definition;
                 $tableRows[] = array_merge(array($styledServiceId, sprintf('alias for "%s"', $alias)), $tagsCount ? array_fill(0, $tagsCount, '') : array());
             } else {
-                $tableRows[] = array_merge(array($styledServiceId, get_class($definition)), $tagsCount ? array_fill(0, $tagsCount, '') : array());
+                $tableRows[] = array_merge(array($styledServiceId, \get_class($definition)), $tagsCount ? array_fill(0, $tagsCount, '') : array());
             }
         }
 
@@ -289,7 +289,7 @@ class TextDescriptor extends Descriptor
         $tableRows[] = array('Tags', $tagInformation);
 
         $calls = $definition->getMethodCalls();
-        if (count($calls) > 0) {
+        if (\count($calls) > 0) {
             $callInformation = array();
             foreach ($calls as $call) {
                 $callInformation[] = $call[0];
@@ -310,7 +310,7 @@ class TextDescriptor extends Descriptor
         }
 
         if ($factory = $definition->getFactory()) {
-            if (is_array($factory)) {
+            if (\is_array($factory)) {
                 if ($factory[0] instanceof Reference) {
                     $tableRows[] = array('Factory Service', $factory[0]);
                 } elseif ($factory[0] instanceof Definition) {
@@ -334,13 +334,13 @@ class TextDescriptor extends Descriptor
                 if ($argument instanceof Reference) {
                     $argumentsInformation[] = sprintf('Service(%s)', (string) $argument);
                 } elseif ($argument instanceof IteratorArgument) {
-                    $argumentsInformation[] = sprintf('Iterator (%d element(s))', count($argument->getValues()));
+                    $argumentsInformation[] = sprintf('Iterator (%d element(s))', \count($argument->getValues()));
                 } elseif ($argument instanceof ServiceLocatorArgument) {
-                    $argumentsInformation[] = sprintf('Service locator (%d element(s))', count($argument->getValues()));
+                    $argumentsInformation[] = sprintf('Service locator (%d element(s))', \count($argument->getValues()));
                 } elseif ($argument instanceof Definition) {
                     $argumentsInformation[] = 'Inlined Service';
                 } else {
-                    $argumentsInformation[] = is_array($argument) ? sprintf('Array (%d element(s))', count($argument)) : $argument;
+                    $argumentsInformation[] = \is_array($argument) ? sprintf('Array (%d element(s))', \count($argument)) : $argument;
                 }
             }
 
@@ -447,15 +447,15 @@ class TextDescriptor extends Descriptor
 
     private function formatCallable($callable): string
     {
-        if (is_array($callable)) {
-            if (is_object($callable[0])) {
-                return sprintf('%s::%s()', get_class($callable[0]), $callable[1]);
+        if (\is_array($callable)) {
+            if (\is_object($callable[0])) {
+                return sprintf('%s::%s()', \get_class($callable[0]), $callable[1]);
             }
 
             return sprintf('%s::%s()', $callable[0], $callable[1]);
         }
 
-        if (is_string($callable)) {
+        if (\is_string($callable)) {
             return sprintf('%s()', $callable);
         }
 
@@ -464,7 +464,7 @@ class TextDescriptor extends Descriptor
         }
 
         if (method_exists($callable, '__invoke')) {
-            return sprintf('%s::__invoke()', get_class($callable));
+            return sprintf('%s::__invoke()', \get_class($callable));
         }
 
         throw new \InvalidArgumentException('Callable is not describable.');
diff --git a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/XmlDescriptor.php b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/XmlDescriptor.php
index c3404ead51..385444d228 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/XmlDescriptor.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Console/Descriptor/XmlDescriptor.php
@@ -164,7 +164,7 @@ class XmlDescriptor extends Descriptor
             $routeXML->setAttribute('name', $name);
         }
 
-        $routeXML->setAttribute('class', get_class($route));
+        $routeXML->setAttribute('class', \get_class($route));
 
         $routeXML->appendChild($pathXML = $dom->createElement('path'));
         $pathXML->setAttribute('regex', $route->compile()->getRegex());
@@ -264,7 +264,7 @@ class XmlDescriptor extends Descriptor
         } else {
             $dom->appendChild($serviceXML = $dom->createElement('service'));
             $serviceXML->setAttribute('id', $id);
-            $serviceXML->setAttribute('class', get_class($service));
+            $serviceXML->setAttribute('class', \get_class($service));
         }
 
         return $dom;
@@ -309,7 +309,7 @@ class XmlDescriptor extends Descriptor
         if ($factory = $definition->getFactory()) {
             $serviceXML->appendChild($factoryXML = $dom->createElement('factory'));
 
-            if (is_array($factory)) {
+            if (\is_array($factory)) {
                 if ($factory[0] instanceof Reference) {
                     $factoryXML->setAttribute('service', (string) $factory[0]);
                 } elseif ($factory[0] instanceof Definition) {
@@ -333,7 +333,7 @@ class XmlDescriptor extends Descriptor
         $serviceXML->setAttribute('file', $definition->getFile());
 
         $calls = $definition->getMethodCalls();
-        if (count($calls) > 0) {
+        if (\count($calls) > 0) {
             $serviceXML->appendChild($callsXML = $dom->createElement('calls'));
             foreach ($calls as $callData) {
                 $callsXML->appendChild($callXML = $dom->createElement('call'));
@@ -377,7 +377,7 @@ class XmlDescriptor extends Descriptor
         foreach ($arguments as $argumentKey => $argument) {
             $argumentXML = $dom->createElement('argument');
 
-            if (is_string($argumentKey)) {
+            if (\is_string($argumentKey)) {
                 $argumentXML->setAttribute('key', $argumentKey);
             }
 
@@ -396,7 +396,7 @@ class XmlDescriptor extends Descriptor
                 }
             } elseif ($argument instanceof Definition) {
                 $argumentXML->appendChild($dom->importNode($this->getContainerDefinitionDocument($argument, null, false, true)->childNodes->item(0), true));
-            } elseif (is_array($argument)) {
+            } elseif (\is_array($argument)) {
                 $argumentXML->setAttribute('type', 'collection');
 
                 foreach ($this->getArgumentNodes($argument, $dom) as $childArgumenXML) {
@@ -478,12 +478,12 @@ class XmlDescriptor extends Descriptor
         $dom = new \DOMDocument('1.0', 'UTF-8');
         $dom->appendChild($callableXML = $dom->createElement('callable'));
 
-        if (is_array($callable)) {
+        if (\is_array($callable)) {
             $callableXML->setAttribute('type', 'function');
 
-            if (is_object($callable[0])) {
+            if (\is_object($callable[0])) {
                 $callableXML->setAttribute('name', $callable[1]);
-                $callableXML->setAttribute('class', get_class($callable[0]));
+                $callableXML->setAttribute('class', \get_class($callable[0]));
             } else {
                 if (0 !== strpos($callable[1], 'parent::')) {
                     $callableXML->setAttribute('name', $callable[1]);
@@ -500,7 +500,7 @@ class XmlDescriptor extends Descriptor
             return $dom;
         }
 
-        if (is_string($callable)) {
+        if (\is_string($callable)) {
             $callableXML->setAttribute('type', 'function');
 
             if (false === strpos($callable, '::')) {
@@ -524,7 +524,7 @@ class XmlDescriptor extends Descriptor
 
         if (method_exists($callable, '__invoke')) {
             $callableXML->setAttribute('type', 'object');
-            $callableXML->setAttribute('name', get_class($callable));
+            $callableXML->setAttribute('name', \get_class($callable));
 
             return $dom;
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Controller/AbstractController.php b/src/Symfony/Bundle/FrameworkBundle/Controller/AbstractController.php
index 7286162c2e..b839335804 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Controller/AbstractController.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Controller/AbstractController.php
@@ -65,7 +65,7 @@ abstract class AbstractController implements ServiceSubscriberInterface
     protected function getParameter(string $name)
     {
         if (!$this->container->has('parameter_bag')) {
-            throw new ServiceNotFoundException('parameter_bag', null, null, array(), sprintf('The "%s::getParameter()" method is missing a parameter bag to work properly. Did you forget to register your controller as a service subscriber? This can be fixed either by using autoconfiguration or by manually wiring a "parameter_bag" in the service locator passed to the controller.', get_class($this)));
+            throw new ServiceNotFoundException('parameter_bag', null, null, array(), sprintf('The "%s::getParameter()" method is missing a parameter bag to work properly. Did you forget to register your controller as a service subscriber? This can be fixed either by using autoconfiguration or by manually wiring a "parameter_bag" in the service locator passed to the controller.', \get_class($this)));
         }
 
         return $this->container->get('parameter_bag')->get($name);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerNameParser.php b/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerNameParser.php
index c2ede8175c..d02a9824ce 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerNameParser.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerNameParser.php
@@ -44,12 +44,12 @@ class ControllerNameParser
      */
     public function parse($controller)
     {
-        if (2 > func_num_args() || func_get_arg(1)) {
+        if (2 > \func_num_args() || func_get_arg(1)) {
             @trigger_error(sprintf('The "%s" class is deprecated since Symfony 4.1.', __CLASS__), E_USER_DEPRECATED);
         }
 
         $parts = explode(':', $controller);
-        if (3 !== count($parts) || in_array('', $parts, true)) {
+        if (3 !== \count($parts) || \in_array('', $parts, true)) {
             throw new \InvalidArgumentException(sprintf('The "%s" controller is not a valid "a:b:c" controller string.', $controller));
         }
 
@@ -131,7 +131,7 @@ class ControllerNameParser
             }
 
             $lev = levenshtein($nonExistentBundleName, $bundleName);
-            if ($lev <= strlen($nonExistentBundleName) / 3 && (null === $alternative || $lev < $shortest)) {
+            if ($lev <= \strlen($nonExistentBundleName) / 3 && (null === $alternative || $lev < $shortest)) {
                 $alternative = $bundleName;
                 $shortest = $lev;
             }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerResolver.php b/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerResolver.php
index d8f2cd8e1a..7ce0f337c1 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerResolver.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerResolver.php
@@ -62,7 +62,7 @@ class ControllerResolver extends ContainerControllerResolver
         if ($controller instanceof AbstractController) {
             if (null === $previousContainer = $controller->setContainer($this->container)) {
                 @trigger_error(sprintf('Auto-injection of the container for "%s" is deprecated since Symfony 4.2. Configure it as a service instead.', $class), E_USER_DEPRECATED);
-                // To be uncommented on Symfony 5:
+            // To be uncommented on Symfony 5:
                 //throw new \LogicException(sprintf('"%s" has no container set, did you forget to define it as a service subscriber?', $class));
             } else {
                 $controller->setContainer($previousContainer);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerTrait.php b/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerTrait.php
index 8d0525dd89..0d58e32940 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerTrait.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Controller/ControllerTrait.php
@@ -358,7 +358,7 @@ trait ControllerTrait
             return;
         }
 
-        if (!is_object($user = $token->getUser())) {
+        if (!\is_object($user = $token->getUser())) {
             // e.g. anonymous authentication
             return;
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Controller/RedirectController.php b/src/Symfony/Bundle/FrameworkBundle/Controller/RedirectController.php
index 45811e5c42..46fd22ca7a 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Controller/RedirectController.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Controller/RedirectController.php
@@ -61,7 +61,7 @@ class RedirectController
         }
 
         $attributes = array();
-        if (false === $ignoreAttributes || is_array($ignoreAttributes)) {
+        if (false === $ignoreAttributes || \is_array($ignoreAttributes)) {
             $attributes = $request->attributes->get('_route_params');
             $attributes = $keepQueryParams ? array_merge($request->query->all(), $attributes) : $attributes;
             unset($attributes['route'], $attributes['permanent'], $attributes['ignoreAttributes'], $attributes['keepRequestMethod'], $attributes['keepQueryParams']);
diff --git a/src/Symfony/Bundle/FrameworkBundle/DataCollector/RouterDataCollector.php b/src/Symfony/Bundle/FrameworkBundle/DataCollector/RouterDataCollector.php
index b7289e793d..114a0621b3 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DataCollector/RouterDataCollector.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DataCollector/RouterDataCollector.php
@@ -24,7 +24,7 @@ class RouterDataCollector extends BaseRouterDataCollector
 {
     public function guessRoute(Request $request, $controller)
     {
-        if (is_array($controller)) {
+        if (\is_array($controller)) {
             $controller = $controller[0];
         }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/TemplatingPass.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/TemplatingPass.php
index b916a27a6d..b6cf261b57 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/TemplatingPass.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/TemplatingPass.php
@@ -41,7 +41,7 @@ class TemplatingPass implements CompilerPassInterface
                 }
             }
 
-            if (count($helpers) > 0) {
+            if (\count($helpers) > 0) {
                 $definition = $container->getDefinition('templating.engine.php');
                 $definition->addMethodCall('setHelpers', array($helpers));
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
index 37d35c1a09..00328b4b5f 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Compiler/UnusedTagsPass.php
@@ -68,7 +68,7 @@ class UnusedTagsPass implements CompilerPassInterface
 
         foreach ($container->findUnusedTags() as $tag) {
             // skip whitelisted tags
-            if (in_array($tag, $this->whitelist)) {
+            if (\in_array($tag, $this->whitelist)) {
                 continue;
             }
 
@@ -79,7 +79,7 @@ class UnusedTagsPass implements CompilerPassInterface
                     continue;
                 }
 
-                if (false !== strpos($definedTag, $tag) || levenshtein($tag, $definedTag) <= strlen($tag) / 3) {
+                if (false !== strpos($definedTag, $tag) || levenshtein($tag, $definedTag) <= \strlen($tag) / 3) {
                     $candidates[] = $definedTag;
                 }
             }
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
index 06f371f1aa..e611d71422 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/Configuration.php
@@ -220,7 +220,7 @@ class Configuration implements ConfigurationInterface
                                 $workflows = $v;
                                 unset($workflows['enabled']);
 
-                                if (1 === count($workflows) && isset($workflows[0]['enabled'])) {
+                                if (1 === \count($workflows) && isset($workflows[0]['enabled'])) {
                                     $workflows = array();
                                 }
 
@@ -300,19 +300,19 @@ class Configuration implements ConfigurationInterface
                                             ->always()
                                             ->then(function ($places) {
                                                 // It's an indexed array of shape  ['place1', 'place2']
-                                                if (isset($places[0]) && is_string($places[0])) {
+                                                if (isset($places[0]) && \is_string($places[0])) {
                                                     return array_map(function (string $place) {
                                                         return array('name' => $place);
                                                     }, $places);
                                                 }
 
                                                 // It's an indexed array, we let the validation occur
-                                                if (isset($places[0]) && is_array($places[0])) {
+                                                if (isset($places[0]) && \is_array($places[0])) {
                                                     return $places;
                                                 }
 
                                                 foreach ($places as $name => $place) {
-                                                    if (is_array($place) && array_key_exists('name', $place)) {
+                                                    if (\is_array($place) && array_key_exists('name', $place)) {
                                                         continue;
                                                     }
                                                     $place['name'] = $name;
@@ -345,12 +345,12 @@ class Configuration implements ConfigurationInterface
                                             ->always()
                                             ->then(function ($transitions) {
                                                 // It's an indexed array, we let the validation occur
-                                                if (isset($transitions[0]) && is_array($transitions[0])) {
+                                                if (isset($transitions[0]) && \is_array($transitions[0])) {
                                                     return $transitions;
                                                 }
 
                                                 foreach ($transitions as $name => $transition) {
-                                                    if (is_array($transition) && array_key_exists('name', $transition)) {
+                                                    if (\is_array($transition) && array_key_exists('name', $transition)) {
                                                         continue;
                                                     }
                                                     $transition['name'] = $name;
@@ -512,11 +512,11 @@ class Configuration implements ConfigurationInterface
                             ->useAttributeAsKey('name')
                             ->prototype('array')
                                 ->beforeNormalization()
-                                    ->ifTrue(function ($v) { return is_array($v) && isset($v['mime_type']); })
+                                    ->ifTrue(function ($v) { return \is_array($v) && isset($v['mime_type']); })
                                     ->then(function ($v) { return $v['mime_type']; })
                                 ->end()
                                 ->beforeNormalization()
-                                    ->ifTrue(function ($v) { return !is_array($v); })
+                                    ->ifTrue(function ($v) { return !\is_array($v); })
                                     ->then(function ($v) { return array($v); })
                                 ->end()
                                 ->prototype('scalar')->end()
@@ -536,7 +536,7 @@ class Configuration implements ConfigurationInterface
                     ->info('templating configuration')
                     ->canBeEnabled()
                     ->beforeNormalization()
-                        ->ifTrue(function ($v) { return false === $v || is_array($v) && false === $v['enabled']; })
+                        ->ifTrue(function ($v) { return false === $v || \is_array($v) && false === $v['enabled']; })
                         ->then(function () { return array('enabled' => false, 'engines' => false); })
                     ->end()
                     ->children()
@@ -550,7 +550,7 @@ class Configuration implements ConfigurationInterface
                                     ->addDefaultChildrenIfNoneSet()
                                     ->prototype('scalar')->defaultValue('FrameworkBundle:Form')->end()
                                     ->validate()
-                                        ->ifTrue(function ($v) {return !in_array('FrameworkBundle:Form', $v); })
+                                        ->ifTrue(function ($v) {return !\in_array('FrameworkBundle:Form', $v); })
                                         ->then(function ($v) {
                                             return array_merge(array('FrameworkBundle:Form'), $v);
                                         })
@@ -567,7 +567,7 @@ class Configuration implements ConfigurationInterface
                             ->requiresAtLeastOneElement()
                             ->canBeUnset()
                             ->beforeNormalization()
-                                ->ifTrue(function ($v) { return !is_array($v) && false !== $v; })
+                                ->ifTrue(function ($v) { return !\is_array($v) && false !== $v; })
                                 ->then(function ($v) { return array($v); })
                             ->end()
                             ->prototype('scalar')->end()
@@ -577,7 +577,7 @@ class Configuration implements ConfigurationInterface
                     ->children()
                         ->arrayNode('loaders')
                             ->beforeNormalization()
-                                ->ifTrue(function ($v) { return !is_array($v); })
+                                ->ifTrue(function ($v) { return !\is_array($v); })
                                 ->then(function ($v) { return array($v); })
                              ->end()
                             ->prototype('scalar')->end()
@@ -605,7 +605,7 @@ class Configuration implements ConfigurationInterface
                         ->arrayNode('base_urls')
                             ->requiresAtLeastOneElement()
                             ->beforeNormalization()
-                                ->ifTrue(function ($v) { return !is_array($v); })
+                                ->ifTrue(function ($v) { return !\is_array($v); })
                                 ->then(function ($v) { return array($v); })
                             ->end()
                             ->prototype('scalar')->end()
@@ -649,7 +649,7 @@ class Configuration implements ConfigurationInterface
                                     ->arrayNode('base_urls')
                                         ->requiresAtLeastOneElement()
                                         ->beforeNormalization()
-                                            ->ifTrue(function ($v) { return !is_array($v); })
+                                            ->ifTrue(function ($v) { return !\is_array($v); })
                                             ->then(function ($v) { return array($v); })
                                         ->end()
                                         ->prototype('scalar')->end()
@@ -747,7 +747,7 @@ class Configuration implements ConfigurationInterface
                             ->prototype('scalar')->end()
                             ->treatFalseLike(array())
                             ->validate()
-                                ->ifTrue(function ($v) { return !is_array($v); })
+                                ->ifTrue(function ($v) { return !\is_array($v); })
                                 ->then(function ($v) { return (array) $v; })
                             ->end()
                         ->end()
@@ -933,7 +933,7 @@ class Configuration implements ConfigurationInterface
                         ->ifString()->then(function ($v) { return array('enabled' => true, 'resources' => $v); })
                     ->end()
                     ->beforeNormalization()
-                        ->ifTrue(function ($v) { return is_array($v) && !isset($v['resources']); })
+                        ->ifTrue(function ($v) { return \is_array($v) && !isset($v['resources']); })
                         ->then(function ($v) {
                             $e = $v['enabled'];
                             unset($v['enabled']);
@@ -951,7 +951,7 @@ class Configuration implements ConfigurationInterface
                                 ->ifString()->then(function ($v) { return array('default' => $v); })
                             ->end()
                             ->beforeNormalization()
-                                ->ifTrue(function ($v) { return is_array($v) && array_keys($v) === range(0, count($v) - 1); })
+                                ->ifTrue(function ($v) { return \is_array($v) && array_keys($v) === range(0, \count($v) - 1); })
                                 ->then(function ($v) { return array('default' => $v); })
                             ->end()
                             ->prototype('array')
diff --git a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
index 28ad3bc887..58f16a2203 100644
--- a/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
+++ b/src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php
@@ -121,7 +121,7 @@ class FrameworkExtension extends Extension
      */
     public function load(array $configs, ContainerBuilder $container)
     {
-        $loader = new XmlFileLoader($container, new FileLocator(dirname(__DIR__).'/Resources/config'));
+        $loader = new XmlFileLoader($container, new FileLocator(\dirname(__DIR__).'/Resources/config'));
 
         $loader->load('web.xml');
         $loader->load('services.xml');
@@ -805,7 +805,7 @@ class FrameworkExtension extends Extension
             $loaders = array_map(function ($loader) { return new Reference($loader); }, $config['loaders']);
 
             // Use a delegation unless only a single loader was registered
-            if (1 === count($loaders)) {
+            if (1 === \count($loaders)) {
                 $container->setAlias('templating.loader', (string) reset($loaders))->setPrivate(true);
             } else {
                 $container->getDefinition('templating.loader.chain')->addArgument($loaders);
@@ -827,7 +827,7 @@ class FrameworkExtension extends Extension
         $engines = array_map(function ($engine) { return new Reference('templating.engine.'.$engine); }, $config['engines']);
 
         // Use a delegation unless only a single engine was registered
-        if (1 === count($engines)) {
+        if (1 === \count($engines)) {
             $container->setAlias('templating', (string) reset($engines))->setPublic(true);
         } else {
             $templateEngineDefinition = $container->getDefinition('templating.engine.delegating');
@@ -843,7 +843,7 @@ class FrameworkExtension extends Extension
         ;
 
         // configure the PHP engine if needed
-        if (in_array('php', $config['engines'], true)) {
+        if (\in_array('php', $config['engines'], true)) {
             $loader->load('templating_php.xml');
 
             $container->setParameter('templating.helper.form.resources', $config['form']['resources']);
@@ -975,17 +975,17 @@ class FrameworkExtension extends Extension
         if (class_exists('Symfony\Component\Validator\Validation')) {
             $r = new \ReflectionClass('Symfony\Component\Validator\Validation');
 
-            $dirs[] = dirname($r->getFileName()).'/Resources/translations';
+            $dirs[] = \dirname($r->getFileName()).'/Resources/translations';
         }
         if (class_exists('Symfony\Component\Form\Form')) {
             $r = new \ReflectionClass('Symfony\Component\Form\Form');
 
-            $dirs[] = dirname($r->getFileName()).'/Resources/translations';
+            $dirs[] = \dirname($r->getFileName()).'/Resources/translations';
         }
         if (class_exists('Symfony\Component\Security\Core\Exception\AuthenticationException')) {
             $r = new \ReflectionClass('Symfony\Component\Security\Core\Exception\AuthenticationException');
 
-            $dirs[] = dirname(dirname($r->getFileName())).'/Resources/translations';
+            $dirs[] = \dirname(\dirname($r->getFileName())).'/Resources/translations';
         }
         $defaultDir = $container->getParameterBag()->resolveValue($config['default_path']);
         $rootDir = $container->getParameter('kernel.root_dir');
@@ -1105,7 +1105,7 @@ class FrameworkExtension extends Extension
 
         if (interface_exists('Symfony\Component\Form\FormInterface')) {
             $reflClass = new \ReflectionClass('Symfony\Component\Form\FormInterface');
-            $fileRecorder('xml', dirname($reflClass->getFileName()).'/Resources/config/validation.xml');
+            $fileRecorder('xml', \dirname($reflClass->getFileName()).'/Resources/config/validation.xml');
         }
 
         foreach ($container->getParameter('kernel.bundles_metadata') as $bundle) {
@@ -1300,7 +1300,7 @@ class FrameworkExtension extends Extension
         }
 
         $fileRecorder = function ($extension, $path) use (&$serializerLoaders) {
-            $definition = new Definition(in_array($extension, array('yaml', 'yml')) ? 'Symfony\Component\Serializer\Mapping\Loader\YamlFileLoader' : 'Symfony\Component\Serializer\Mapping\Loader\XmlFileLoader', array($path));
+            $definition = new Definition(\in_array($extension, array('yaml', 'yml')) ? 'Symfony\Component\Serializer\Mapping\Loader\YamlFileLoader' : 'Symfony\Component\Serializer\Mapping\Loader\XmlFileLoader', array($path));
             $definition->setPublic(false);
             $serializerLoaders[] = $definition;
         };
@@ -1378,7 +1378,7 @@ class FrameworkExtension extends Extension
         $loader->load('lock.xml');
 
         foreach ($config['resources'] as $resourceName => $resourceStores) {
-            if (0 === count($resourceStores)) {
+            if (0 === \count($resourceStores)) {
                 continue;
             }
 
@@ -1419,7 +1419,7 @@ class FrameworkExtension extends Extension
             }
 
             // Wrap array of stores with CombinedStore
-            if (count($storeDefinitions) > 1) {
+            if (\count($storeDefinitions) > 1) {
                 $combinedDefinition = new ChildDefinition('lock.store.combined.abstract');
                 $combinedDefinition->replaceArgument(0, $storeDefinitions);
                 $container->setDefinition('lock.'.$resourceName.'.store', $combinedDefinition);
@@ -1633,7 +1633,7 @@ class FrameworkExtension extends Extension
      */
     public function getXsdValidationBasePath()
     {
-        return dirname(__DIR__).'/Resources/config/schema';
+        return \dirname(__DIR__).'/Resources/config/schema';
     }
 
     public function getNamespace()
diff --git a/src/Symfony/Bundle/FrameworkBundle/EventListener/ResolveControllerNameSubscriber.php b/src/Symfony/Bundle/FrameworkBundle/EventListener/ResolveControllerNameSubscriber.php
index 1e6a37fd99..d4186daef6 100644
--- a/src/Symfony/Bundle/FrameworkBundle/EventListener/ResolveControllerNameSubscriber.php
+++ b/src/Symfony/Bundle/FrameworkBundle/EventListener/ResolveControllerNameSubscriber.php
@@ -35,7 +35,7 @@ class ResolveControllerNameSubscriber implements EventSubscriberInterface
     public function onKernelRequest(GetResponseEvent $event)
     {
         $controller = $event->getRequest()->attributes->get('_controller');
-        if (is_string($controller) && false === strpos($controller, '::') && 2 === substr_count($controller, ':')) {
+        if (\is_string($controller) && false === strpos($controller, '::') && 2 === substr_count($controller, ':')) {
             // controller in the a:b:c notation then
             $event->getRequest()->attributes->set('_controller', $this->parser->parse($controller, false));
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Routing/DelegatingLoader.php b/src/Symfony/Bundle/FrameworkBundle/Routing/DelegatingLoader.php
index 709fc65faf..f7cb2f18da 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Routing/DelegatingLoader.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Routing/DelegatingLoader.php
@@ -78,7 +78,7 @@ class DelegatingLoader extends BaseDelegatingLoader
             if ($this->defaultOptions) {
                 $route->setOptions($route->getOptions() + $this->defaultOptions);
             }
-            if (!is_string($controller = $route->getDefault('_controller'))) {
+            if (!\is_string($controller = $route->getDefault('_controller'))) {
                 continue;
             }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Routing/Router.php b/src/Symfony/Bundle/FrameworkBundle/Routing/Router.php
index 055609c488..679dce00f7 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Routing/Router.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Routing/Router.php
@@ -140,7 +140,7 @@ class Router extends BaseRouter implements WarmableInterface, ServiceSubscriberI
      */
     private function resolve($value)
     {
-        if (is_array($value)) {
+        if (\is_array($value)) {
             foreach ($value as $key => $val) {
                 $value[$key] = $this->resolve($val);
             }
@@ -148,7 +148,7 @@ class Router extends BaseRouter implements WarmableInterface, ServiceSubscriberI
             return $value;
         }
 
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             return $value;
         }
 
@@ -164,7 +164,7 @@ class Router extends BaseRouter implements WarmableInterface, ServiceSubscriberI
 
             $resolved = ($this->paramFetcher)($match[1]);
 
-            if (is_string($resolved) || is_numeric($resolved)) {
+            if (\is_string($resolved) || is_numeric($resolved)) {
                 $this->collectedParameters[$match[1]] = $resolved;
 
                 return (string) $resolved;
@@ -175,7 +175,7 @@ class Router extends BaseRouter implements WarmableInterface, ServiceSubscriberI
                 'must be a string or numeric, but it is of type %s.',
                 $match[1],
                 $value,
-                gettype($resolved)
+                \gettype($resolved)
                 )
             );
         }, $value);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/DelegatingEngine.php b/src/Symfony/Bundle/FrameworkBundle/Templating/DelegatingEngine.php
index 81658ffa7b..60dda1c9b4 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/DelegatingEngine.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/DelegatingEngine.php
@@ -66,7 +66,7 @@ class DelegatingEngine extends BaseDelegatingEngine implements EngineInterface
     private function resolveEngines()
     {
         foreach ($this->engines as $i => $engine) {
-            if (is_string($engine)) {
+            if (\is_string($engine)) {
                 $this->engines[$i] = $this->container->get($engine);
             }
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/GlobalVariables.php b/src/Symfony/Bundle/FrameworkBundle/Templating/GlobalVariables.php
index d1daf760dc..4e07b9b5b8 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/GlobalVariables.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/GlobalVariables.php
@@ -49,7 +49,7 @@ class GlobalVariables
         }
 
         $user = $token->getUser();
-        if (!is_object($user)) {
+        if (!\is_object($user)) {
             return;
         }
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/CodeHelper.php b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/CodeHelper.php
index 209c77fa54..a1cddf2808 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/CodeHelper.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/CodeHelper.php
@@ -85,7 +85,7 @@ class CodeHelper extends Helper
                 $short = array_pop($parts);
                 $formattedValue = sprintf('<em>object</em>(<abbr title="%s">%s</abbr>)', $item[1], $short);
             } elseif ('array' === $item[0]) {
-                $formattedValue = sprintf('<em>array</em>(%s)', is_array($item[1]) ? $this->formatArgs($item[1]) : $item[1]);
+                $formattedValue = sprintf('<em>array</em>(%s)', \is_array($item[1]) ? $this->formatArgs($item[1]) : $item[1]);
             } elseif ('string' === $item[0]) {
                 $formattedValue = sprintf("'%s'", htmlspecialchars($item[1], ENT_QUOTES, $this->getCharset()));
             } elseif ('null' === $item[0]) {
@@ -98,7 +98,7 @@ class CodeHelper extends Helper
                 $formattedValue = str_replace("\n", '', var_export(htmlspecialchars((string) $item[1], ENT_QUOTES, $this->getCharset()), true));
             }
 
-            $result[] = is_int($key) ? $formattedValue : sprintf("'%s' => %s", $key, $formattedValue);
+            $result[] = \is_int($key) ? $formattedValue : sprintf("'%s' => %s", $key, $formattedValue);
         }
 
         return implode(', ', $result);
@@ -115,7 +115,7 @@ class CodeHelper extends Helper
     public function fileExcerpt($file, $line)
     {
         if (is_readable($file)) {
-            if (extension_loaded('fileinfo')) {
+            if (\extension_loaded('fileinfo')) {
                 $finfo = new \finfo();
 
                 // Check if the file is an application/octet-stream (eg. Phar file) because highlight_file cannot parse these files
@@ -132,7 +132,7 @@ class CodeHelper extends Helper
             $content = explode('<br />', $code);
 
             $lines = array();
-            for ($i = max($line - 3, 1), $max = min($line + 3, count($content)); $i <= $max; ++$i) {
+            for ($i = max($line - 3, 1), $max = min($line + 3, \count($content)); $i <= $max; ++$i) {
                 $lines[] = '<li'.($i == $line ? ' class="selected"' : '').'><code>'.self::fixCodeMarkup($content[$i - 1]).'</code></li>';
             }
 
@@ -183,7 +183,7 @@ class CodeHelper extends Helper
     public function getFileLink($file, $line)
     {
         if ($fmt = $this->fileLinkFormat) {
-            return is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line);
+            return \is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line);
         }
 
         return false;
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/StopwatchHelper.php b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/StopwatchHelper.php
index 47a9cf80eb..72269ec69d 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/StopwatchHelper.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/Helper/StopwatchHelper.php
@@ -37,7 +37,7 @@ class StopwatchHelper extends Helper
     {
         if (null !== $this->stopwatch) {
             if (method_exists($this->stopwatch, $method)) {
-                return call_user_func_array(array($this->stopwatch, $method), $arguments);
+                return \call_user_func_array(array($this->stopwatch, $method), $arguments);
             }
 
             throw new \BadMethodCallException(sprintf('Method "%s" of Stopwatch does not exist', $method));
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/PhpEngine.php b/src/Symfony/Bundle/FrameworkBundle/Templating/PhpEngine.php
index 4f1c7563cd..0ff0993e80 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/PhpEngine.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/PhpEngine.php
@@ -46,7 +46,7 @@ class PhpEngine extends BasePhpEngine implements EngineInterface
             throw new \InvalidArgumentException(sprintf('The helper "%s" is not defined.', $name));
         }
 
-        if (is_string($this->helpers[$name])) {
+        if (\is_string($this->helpers[$name])) {
             $this->helpers[$name] = $this->container->get($this->helpers[$name]);
             $this->helpers[$name]->setCharset($this->charset);
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Templating/TemplateFilenameParser.php b/src/Symfony/Bundle/FrameworkBundle/Templating/TemplateFilenameParser.php
index df3ab19c4d..b6870334c6 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Templating/TemplateFilenameParser.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Templating/TemplateFilenameParser.php
@@ -34,7 +34,7 @@ class TemplateFilenameParser implements TemplateNameParserInterface
         $parts = explode('/', str_replace('\\', '/', $name));
 
         $elements = explode('.', array_pop($parts));
-        if (3 > count($elements)) {
+        if (3 > \count($elements)) {
             return false;
         }
         $engine = array_pop($elements);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/SerializerCacheWarmerTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/SerializerCacheWarmerTest.php
index 86aee6e0cc..fdd40d48d6 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/SerializerCacheWarmerTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/SerializerCacheWarmerTest.php
@@ -39,7 +39,7 @@ class SerializerCacheWarmerTest extends TestCase
         $fallbackPool = new ArrayAdapter();
 
         $warmer = new SerializerCacheWarmer($loaders, $file, $fallbackPool);
-        $warmer->warmUp(dirname($file));
+        $warmer->warmUp(\dirname($file));
 
         $this->assertFileExists($file);
 
@@ -68,7 +68,7 @@ class SerializerCacheWarmerTest extends TestCase
         $fallbackPool = new ArrayAdapter();
 
         $warmer = new SerializerCacheWarmer(array(), $file, $fallbackPool);
-        $warmer->warmUp(dirname($file));
+        $warmer->warmUp(\dirname($file));
 
         $this->assertFileExists($file);
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/TemplatePathsCacheWarmerTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/TemplatePathsCacheWarmerTest.php
index 74a33f3b43..d3120ef13a 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/TemplatePathsCacheWarmerTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/TemplatePathsCacheWarmerTest.php
@@ -74,7 +74,7 @@ class TemplatePathsCacheWarmerTest extends TestCase
             ->expects($this->once())
             ->method('locate')
             ->with($template->getPath())
-            ->will($this->returnValue(dirname($this->tmpDir).'/path/to/template.html.twig'));
+            ->will($this->returnValue(\dirname($this->tmpDir).'/path/to/template.html.twig'));
 
         $warmer = new TemplatePathsCacheWarmer($this->templateFinder, $this->templateLocator);
         $warmer->warmUp($this->tmpDir);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/ValidatorCacheWarmerTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/ValidatorCacheWarmerTest.php
index f8d3710c6d..47c88f1a20 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/ValidatorCacheWarmerTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/CacheWarmer/ValidatorCacheWarmerTest.php
@@ -35,7 +35,7 @@ class ValidatorCacheWarmerTest extends TestCase
         $fallbackPool = new ArrayAdapter();
 
         $warmer = new ValidatorCacheWarmer($validatorBuilder, $file, $fallbackPool);
-        $warmer->warmUp(dirname($file));
+        $warmer->warmUp(\dirname($file));
 
         $this->assertFileExists($file);
 
@@ -64,7 +64,7 @@ class ValidatorCacheWarmerTest extends TestCase
         $fallbackPool = new ArrayAdapter();
 
         $warmer = new ValidatorCacheWarmer($validatorBuilder, $file, $fallbackPool);
-        $warmer->warmUp(dirname($file));
+        $warmer->warmUp(\dirname($file));
 
         $this->assertFileExists($file);
 
@@ -93,7 +93,7 @@ class ValidatorCacheWarmerTest extends TestCase
         $fallbackPool = new ArrayAdapter();
 
         $warmer = new ValidatorCacheWarmer($validatorBuilder, $file, $fallbackPool);
-        $warmer->warmUp(dirname($file));
+        $warmer->warmUp(\dirname($file));
 
         $this->assertFileExists($file);
 
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Command/CacheClearCommand/CacheClearCommandTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Command/CacheClearCommand/CacheClearCommandTest.php
index 6ebdb1a1b4..20888f2c70 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Command/CacheClearCommand/CacheClearCommandTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Command/CacheClearCommand/CacheClearCommandTest.php
@@ -67,7 +67,7 @@ class CacheClearCommandTest extends TestCase
         // check that app kernel file present in meta file of container's cache
         $containerClass = $this->kernel->getContainer()->getParameter('kernel.container_class');
         $containerRef = new \ReflectionClass($containerClass);
-        $containerFile = dirname(dirname($containerRef->getFileName())).'/'.$containerClass.'.php';
+        $containerFile = \dirname(\dirname($containerRef->getFileName())).'/'.$containerClass.'.php';
         $containerMetaFile = $containerFile.'.meta';
         $kernelRef = new \ReflectionObject($this->kernel);
         $kernelFile = $kernelRef->getFileName();
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/CachePoolPrunerPassTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/CachePoolPrunerPassTest.php
index ec7e620064..df9a49b428 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/CachePoolPrunerPassTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/CachePoolPrunerPassTest.php
@@ -45,8 +45,8 @@ class CachePoolPrunerPassTest extends TestCase
     {
         $container = new ContainerBuilder();
 
-        $definitionsBefore = count($container->getDefinitions());
-        $aliasesBefore = count($container->getAliases());
+        $definitionsBefore = \count($container->getDefinitions());
+        $aliasesBefore = \count($container->getAliases());
 
         $pass = new CachePoolPrunerPass();
         $pass->process($container);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/LoggingTranslatorPassTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/LoggingTranslatorPassTest.php
index 2a9b332914..7788df0c7b 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/LoggingTranslatorPassTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/Compiler/LoggingTranslatorPassTest.php
@@ -51,8 +51,8 @@ class LoggingTranslatorPassTest extends TestCase
         $container->register('identity_translator');
         $container->setAlias('translator', 'identity_translator');
 
-        $definitionsBefore = count($container->getDefinitions());
-        $aliasesBefore = count($container->getAliases());
+        $definitionsBefore = \count($container->getDefinitions());
+        $aliasesBefore = \count($container->getAliases());
 
         $pass = new LoggingTranslatorPass();
         $pass->process($container);
@@ -68,8 +68,8 @@ class LoggingTranslatorPassTest extends TestCase
         $container->register('monolog.logger');
         $container->setAlias('logger', 'monolog.logger');
 
-        $definitionsBefore = count($container->getDefinitions());
-        $aliasesBefore = count($container->getAliases());
+        $definitionsBefore = \count($container->getDefinitions());
+        $aliasesBefore = \count($container->getAliases());
 
         $pass = new LoggingTranslatorPass();
         $pass->process($container);
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
index b6ce997751..8dbda3e78d 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/ConfigurationTest.php
@@ -18,7 +18,6 @@ use Symfony\Component\Config\Definition\Exception\InvalidConfigurationException;
 use Symfony\Component\Config\Definition\Processor;
 use Symfony\Component\Lock\Store\SemaphoreStore;
 use Symfony\Component\Messenger\MessageBusInterface;
-use Symfony\Component\Serializer\Serializer;
 
 class ConfigurationTest extends TestCase
 {
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php
index 7ebb45c00a..1e3b72376a 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/DependencyInjection/FrameworkExtensionTest.php
@@ -270,7 +270,7 @@ abstract class FrameworkExtensionTest extends TestCase
 
         $this->assertTrue($container->hasDefinition('workflow.registry'), 'Workflow registry is registered as a service');
         $registryDefinition = $container->getDefinition('workflow.registry');
-        $this->assertGreaterThan(0, count($registryDefinition->getMethodCalls()));
+        $this->assertGreaterThan(0, \count($registryDefinition->getMethodCalls()));
     }
 
     /**
@@ -657,19 +657,19 @@ abstract class FrameworkExtensionTest extends TestCase
         $files = array_map('realpath', $options['resource_files']['en']);
         $ref = new \ReflectionClass('Symfony\Component\Validator\Validation');
         $this->assertContains(
-            strtr(dirname($ref->getFileName()).'/Resources/translations/validators.en.xlf', '/', DIRECTORY_SEPARATOR),
+            strtr(\dirname($ref->getFileName()).'/Resources/translations/validators.en.xlf', '/', DIRECTORY_SEPARATOR),
             $files,
             '->registerTranslatorConfiguration() finds Validator translation resources'
         );
         $ref = new \ReflectionClass('Symfony\Component\Form\Form');
         $this->assertContains(
-            strtr(dirname($ref->getFileName()).'/Resources/translations/validators.en.xlf', '/', DIRECTORY_SEPARATOR),
+            strtr(\dirname($ref->getFileName()).'/Resources/translations/validators.en.xlf', '/', DIRECTORY_SEPARATOR),
             $files,
             '->registerTranslatorConfiguration() finds Form translation resources'
         );
         $ref = new \ReflectionClass('Symfony\Component\Security\Core\Security');
         $this->assertContains(
-            strtr(dirname($ref->getFileName()).'/Resources/translations/security.en.xlf', '/', DIRECTORY_SEPARATOR),
+            strtr(\dirname($ref->getFileName()).'/Resources/translations/security.en.xlf', '/', DIRECTORY_SEPARATOR),
             $files,
             '->registerTranslatorConfiguration() finds Security translation resources'
         );
@@ -727,7 +727,7 @@ abstract class FrameworkExtensionTest extends TestCase
 
         $ref = new \ReflectionClass('Symfony\Component\Form\Form');
         $xmlMappings = array(
-            dirname($ref->getFileName()).'/Resources/config/validation.xml',
+            \dirname($ref->getFileName()).'/Resources/config/validation.xml',
             strtr($projectDir.'/config/validator/foo.xml', '/', DIRECTORY_SEPARATOR),
         );
 
@@ -1244,7 +1244,7 @@ abstract class FrameworkExtensionTest extends TestCase
 
     protected function createContainerFromFile($file, $data = array(), $resetCompilerPasses = true, $compile = true)
     {
-        $cacheKey = md5(get_class($this).$file.serialize($data));
+        $cacheKey = md5(\get_class($this).$file.serialize($data));
         if ($compile && isset(self::$containerCache[$cacheKey])) {
             return self::$containerCache[$cacheKey];
         }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/Bundle/TestBundle/Controller/AnnotatedController.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/Bundle/TestBundle/Controller/AnnotatedController.php
index 98a3ace982..96543ce10f 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/Bundle/TestBundle/Controller/AnnotatedController.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/Bundle/TestBundle/Controller/AnnotatedController.php
@@ -22,7 +22,7 @@ class AnnotatedController
      */
     public function requestDefaultNullAction(Request $request = null)
     {
-        return new Response($request ? get_class($request) : null);
+        return new Response($request ? \get_class($request) : null);
     }
 
     /**
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/WebTestCase.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/WebTestCase.php
index a1c50e59fd..b25ab8e5a6 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/WebTestCase.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Functional/WebTestCase.php
@@ -68,6 +68,6 @@ class WebTestCase extends BaseWebTestCase
 
     protected static function getVarDir()
     {
-        return 'FB'.substr(strrchr(get_called_class(), '\\'), 1);
+        return 'FB'.substr(strrchr(\get_called_class(), '\\'), 1);
     }
 }
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperDivLayoutTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperDivLayoutTest.php
index eb1789f9d1..40ba682e2c 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperDivLayoutTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperDivLayoutTest.php
@@ -32,7 +32,7 @@ class FormHelperDivLayoutTest extends AbstractDivLayoutTest
         // should be moved to the Form component once absolute file paths are supported
         // by the default name parser in the Templating component
         $reflClass = new \ReflectionClass('Symfony\Bundle\FrameworkBundle\FrameworkBundle');
-        $root = realpath(dirname($reflClass->getFileName()).'/Resources/views');
+        $root = realpath(\dirname($reflClass->getFileName()).'/Resources/views');
         $rootTheme = realpath(__DIR__.'/Resources');
         $templateNameParser = new StubTemplateNameParser($root, $rootTheme);
         $loader = new FilesystemLoader(array());
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperTableLayoutTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperTableLayoutTest.php
index dcec5b3002..7e0acdc4c4 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperTableLayoutTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/Helper/FormHelperTableLayoutTest.php
@@ -56,7 +56,7 @@ class FormHelperTableLayoutTest extends AbstractTableLayoutTest
         // should be moved to the Form component once absolute file paths are supported
         // by the default name parser in the Templating component
         $reflClass = new \ReflectionClass('Symfony\Bundle\FrameworkBundle\FrameworkBundle');
-        $root = realpath(dirname($reflClass->getFileName()).'/Resources/views');
+        $root = realpath(\dirname($reflClass->getFileName()).'/Resources/views');
         $rootTheme = realpath(__DIR__.'/Resources');
         $templateNameParser = new StubTemplateNameParser($root, $rootTheme);
         $loader = new FilesystemLoader(array());
diff --git a/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/TemplateNameParserTest.php b/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/TemplateNameParserTest.php
index 7f7829b9c0..3bcd288e21 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/TemplateNameParserTest.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Tests/Templating/TemplateNameParserTest.php
@@ -27,7 +27,7 @@ class TemplateNameParserTest extends TestCase
             ->expects($this->any())
             ->method('getBundle')
             ->will($this->returnCallback(function ($bundle) {
-                if (in_array($bundle, array('SensioFooBundle', 'SensioCmsFooBundle', 'FooBundle'))) {
+                if (\in_array($bundle, array('SensioFooBundle', 'SensioCmsFooBundle', 'FooBundle'))) {
                     return true;
                 }
 
diff --git a/src/Symfony/Bundle/SecurityBundle/Command/UserPasswordEncoderCommand.php b/src/Symfony/Bundle/SecurityBundle/Command/UserPasswordEncoderCommand.php
index 0b36054fd0..b3dccfd065 100644
--- a/src/Symfony/Bundle/SecurityBundle/Command/UserPasswordEncoderCommand.php
+++ b/src/Symfony/Bundle/SecurityBundle/Command/UserPasswordEncoderCommand.php
@@ -147,7 +147,7 @@ EOF
         $encodedPassword = $encoder->encodePassword($password, $salt);
 
         $rows = array(
-            array('Encoder used', get_class($encoder)),
+            array('Encoder used', \get_class($encoder)),
             array('Encoded password', $encodedPassword),
         );
         if (!$emptySalt) {
@@ -156,7 +156,7 @@ EOF
         $io->table(array('Key', 'Value'), $rows);
 
         if (!$emptySalt) {
-            $errorIo->note(sprintf('Make sure that your salt storage field fits the salt length: %s chars', strlen($salt)));
+            $errorIo->note(sprintf('Make sure that your salt storage field fits the salt length: %s chars', \strlen($salt)));
         } elseif ($saltlessWithoutEmptySalt) {
             $errorIo->note('Self-salting encoder used: the encoder generated its own built-in salt.');
         }
@@ -195,7 +195,7 @@ EOF
             throw new RuntimeException('There are no configured encoders for the "security" extension.');
         }
 
-        if (!$input->isInteractive() || 1 === count($this->userClasses)) {
+        if (!$input->isInteractive() || 1 === \count($this->userClasses)) {
             return reset($this->userClasses);
         }
 
diff --git a/src/Symfony/Bundle/SecurityBundle/DataCollector/SecurityDataCollector.php b/src/Symfony/Bundle/SecurityBundle/DataCollector/SecurityDataCollector.php
index 2e3a085a92..268147b440 100644
--- a/src/Symfony/Bundle/SecurityBundle/DataCollector/SecurityDataCollector.php
+++ b/src/Symfony/Bundle/SecurityBundle/DataCollector/SecurityDataCollector.php
@@ -103,7 +103,7 @@ class SecurityDataCollector extends DataCollector implements LateDataCollectorIn
             if (null !== $this->roleHierarchy) {
                 $allRoles = $this->roleHierarchy->getReachableRoles($assignedRoles);
                 foreach ($allRoles as $role) {
-                    if (!in_array($role, $assignedRoles, true)) {
+                    if (!\in_array($role, $assignedRoles, true)) {
                         $inheritedRoles[] = $role;
                     }
                 }
@@ -125,7 +125,7 @@ class SecurityDataCollector extends DataCollector implements LateDataCollectorIn
                 'impersonator_user' => $impersonatorUser,
                 'impersonation_exit_path' => null,
                 'token' => $token,
-                'token_class' => $this->hasVarDumper ? new ClassStub(get_class($token)) : get_class($token),
+                'token_class' => $this->hasVarDumper ? new ClassStub(\get_class($token)) : \get_class($token),
                 'logout_url' => $logoutUrl,
                 'user' => $token->getUsername(),
                 'roles' => array_map(function (Role $role) { return $role->getRole(); }, $assignedRoles),
@@ -140,7 +140,7 @@ class SecurityDataCollector extends DataCollector implements LateDataCollectorIn
             $this->data['voter_strategy'] = $this->accessDecisionManager->getStrategy();
 
             foreach ($this->accessDecisionManager->getVoters() as $voter) {
-                $this->data['voters'][] = $this->hasVarDumper ? new ClassStub(get_class($voter)) : get_class($voter);
+                $this->data['voters'][] = $this->hasVarDumper ? new ClassStub(\get_class($voter)) : \get_class($voter);
             }
         } else {
             $this->data['access_decision_log'] = array();
diff --git a/src/Symfony/Bundle/SecurityBundle/Debug/WrappedListener.php b/src/Symfony/Bundle/SecurityBundle/Debug/WrappedListener.php
index 85878e2193..1715fbf117 100644
--- a/src/Symfony/Bundle/SecurityBundle/Debug/WrappedListener.php
+++ b/src/Symfony/Bundle/SecurityBundle/Debug/WrappedListener.php
@@ -53,7 +53,7 @@ final class WrappedListener implements ListenerInterface
      */
     public function __call($method, $arguments)
     {
-        return call_user_func_array(array($this->listener, $method), $arguments);
+        return \call_user_func_array(array($this->listener, $method), $arguments);
     }
 
     public function getWrappedListener(): ListenerInterface
@@ -64,7 +64,7 @@ final class WrappedListener implements ListenerInterface
     public function getInfo(): array
     {
         if (null === $this->stub) {
-            $this->stub = self::$hasVarDumper ? new ClassStub(get_class($this->listener)) : get_class($this->listener);
+            $this->stub = self::$hasVarDumper ? new ClassStub(\get_class($this->listener)) : \get_class($this->listener);
         }
 
         return array(
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php
index d3353019f6..cada62b3f3 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/MainConfiguration.php
@@ -112,7 +112,7 @@ class MainConfiguration implements ConfigurationInterface
                         ->performNoDeepMerging()
                         ->beforeNormalization()->ifString()->then(function ($v) { return array('value' => $v); })->end()
                         ->beforeNormalization()
-                            ->ifTrue(function ($v) { return is_array($v) && isset($v['value']); })
+                            ->ifTrue(function ($v) { return \is_array($v) && isset($v['value']); })
                             ->then(function ($v) { return preg_split('/\s*,\s*/', $v['value']); })
                         ->end()
                         ->prototype('scalar')->end()
@@ -218,7 +218,7 @@ class MainConfiguration implements ConfigurationInterface
                 ->children()
                     ->arrayNode('delete_cookies')
                         ->beforeNormalization()
-                            ->ifTrue(function ($v) { return is_array($v) && is_int(key($v)); })
+                            ->ifTrue(function ($v) { return \is_array($v) && \is_int(key($v)); })
                             ->then(function ($v) { return array_map(function ($v) { return array('name' => $v); }, $v); })
                         ->end()
                         ->useAttributeAsKey('name')
@@ -346,11 +346,11 @@ class MainConfiguration implements ConfigurationInterface
 
         $providerNodeBuilder
             ->validate()
-                ->ifTrue(function ($v) { return count($v) > 1; })
+                ->ifTrue(function ($v) { return \count($v) > 1; })
                 ->thenInvalid('You cannot set multiple provider types for the same provider')
             ->end()
             ->validate()
-                ->ifTrue(function ($v) { return 0 === count($v); })
+                ->ifTrue(function ($v) { return 0 === \count($v); })
                 ->thenInvalid('You must set a provider definition for the provider.')
             ->end()
         ;
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/AbstractFactory.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/AbstractFactory.php
index 26fa75572c..195ef4c23a 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/AbstractFactory.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/AbstractFactory.php
@@ -81,7 +81,7 @@ abstract class AbstractFactory implements SecurityFactoryInterface
         ;
 
         foreach (array_merge($this->options, $this->defaultSuccessHandlerOptions, $this->defaultFailureHandlerOptions) as $name => $default) {
-            if (is_bool($default)) {
+            if (\is_bool($default)) {
                 $builder->booleanNode($name)->defaultValue($default);
             } else {
                 $builder->scalarNode($name)->defaultValue($default);
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/GuardAuthenticationFactory.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/GuardAuthenticationFactory.php
index d18d2a92f0..643f5d2fc2 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/GuardAuthenticationFactory.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/GuardAuthenticationFactory.php
@@ -112,7 +112,7 @@ class GuardAuthenticationFactory implements SecurityFactoryInterface
         }
 
         $authenticatorIds = $config['authenticators'];
-        if (1 == count($authenticatorIds)) {
+        if (1 == \count($authenticatorIds)) {
             // if there is only one authenticator, use that as the entry point
             return array_shift($authenticatorIds);
         }
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RememberMeFactory.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RememberMeFactory.php
index 6466cc37a6..7594e66179 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RememberMeFactory.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/Security/Factory/RememberMeFactory.php
@@ -95,7 +95,7 @@ class RememberMeFactory implements SecurityFactoryInterface
                 $userProviders[] = new Reference('security.user.provider.concrete.'.$providerName);
             }
         }
-        if (0 === count($userProviders)) {
+        if (0 === \count($userProviders)) {
             throw new \RuntimeException('You must configure at least one remember-me aware listener (such as form-login) for each firewall that has remember-me enabled.');
         }
 
@@ -140,7 +140,7 @@ class RememberMeFactory implements SecurityFactoryInterface
         ;
 
         foreach ($this->options as $name => $value) {
-            if (is_bool($value)) {
+            if (\is_bool($value)) {
                 $builder->booleanNode($name)->defaultValue($value);
             } else {
                 $builder->scalarNode($name)->defaultValue($value);
diff --git a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/SecurityExtension.php b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/SecurityExtension.php
index 0d87bcb6ee..aaa77ee21a 100644
--- a/src/Symfony/Bundle/SecurityBundle/DependencyInjection/SecurityExtension.php
+++ b/src/Symfony/Bundle/SecurityBundle/DependencyInjection/SecurityExtension.php
@@ -127,7 +127,7 @@ class SecurityExtension extends Extension
 
     private function createRoleHierarchy(array $config, ContainerBuilder $container)
     {
-        if (!isset($config['role_hierarchy']) || 0 === count($config['role_hierarchy'])) {
+        if (!isset($config['role_hierarchy']) || 0 === \count($config['role_hierarchy'])) {
             $container->removeDefinition('security.access.role_hierarchy_voter');
 
             return;
@@ -158,7 +158,7 @@ class SecurityExtension extends Extension
         }
 
         // allow cache warm-up for expressions
-        if (count($this->expressions)) {
+        if (\count($this->expressions)) {
             $container->getDefinition('security.cache_warmer.expression')
                 ->replaceArgument(0, new IteratorArgument(array_values($this->expressions)));
         } else {
@@ -267,7 +267,7 @@ class SecurityExtension extends Extension
                 throw new InvalidConfigurationException(sprintf('Invalid firewall "%s": user provider "%s" not found.', $id, $firewall['provider']));
             }
             $defaultProvider = $providerIds[$normalizedName];
-        } elseif (1 === count($providerIds)) {
+        } elseif (1 === \count($providerIds)) {
             $defaultProvider = reset($providerIds);
         }
 
@@ -330,7 +330,7 @@ class SecurityExtension extends Extension
             }
 
             // add cookie logout handler
-            if (count($firewall['logout']['delete_cookies']) > 0) {
+            if (\count($firewall['logout']['delete_cookies']) > 0) {
                 $cookieHandlerId = 'security.logout.handler.cookie_clearing.'.$id;
                 $cookieHandler = $container->setDefinition($cookieHandlerId, new ChildDefinition('security.logout.handler.cookie_clearing'));
                 $cookieHandler->addArgument($firewall['logout']['delete_cookies']);
@@ -409,7 +409,7 @@ class SecurityExtension extends Extension
             return $this->contextListeners[$contextKey];
         }
 
-        $listenerId = 'security.context_listener.'.count($this->contextListeners);
+        $listenerId = 'security.context_listener.'.\count($this->contextListeners);
         $listener = $container->setDefinition($listenerId, new ChildDefinition('security.context_listener'));
         $listener->replaceArgument(2, $contextKey);
 
@@ -682,7 +682,7 @@ class SecurityExtension extends Extension
 
         // only add arguments that are necessary
         $arguments = array($path, $host, $methods, $ip, $attributes);
-        while (count($arguments) > 0 && !end($arguments)) {
+        while (\count($arguments) > 0 && !end($arguments)) {
             array_pop($arguments);
         }
 
diff --git a/src/Symfony/Bundle/SecurityBundle/Security/FirewallConfig.php b/src/Symfony/Bundle/SecurityBundle/Security/FirewallConfig.php
index 308442810b..795f5b3cc0 100644
--- a/src/Symfony/Bundle/SecurityBundle/Security/FirewallConfig.php
+++ b/src/Symfony/Bundle/SecurityBundle/Security/FirewallConfig.php
@@ -66,7 +66,7 @@ final class FirewallConfig
 
     public function allowsAnonymous(): bool
     {
-        return in_array('anonymous', $this->listeners, true);
+        return \in_array('anonymous', $this->listeners, true);
     }
 
     public function isStateless(): bool
diff --git a/src/Symfony/Bundle/SecurityBundle/Security/FirewallContext.php b/src/Symfony/Bundle/SecurityBundle/Security/FirewallContext.php
index 07aef00394..a83cf69b8b 100644
--- a/src/Symfony/Bundle/SecurityBundle/Security/FirewallContext.php
+++ b/src/Symfony/Bundle/SecurityBundle/Security/FirewallContext.php
@@ -41,7 +41,7 @@ class FirewallContext
             $this->logoutListener = $logoutListener;
             $this->config = $config;
         } else {
-            throw new \InvalidArgumentException(sprintf('Argument 3 passed to %s() must be instance of %s or null, %s given.', __METHOD__, LogoutListener::class, is_object($logoutListener) ? get_class($logoutListener) : gettype($logoutListener)));
+            throw new \InvalidArgumentException(sprintf('Argument 3 passed to %s() must be instance of %s or null, %s given.', __METHOD__, LogoutListener::class, \is_object($logoutListener) ? \get_class($logoutListener) : \gettype($logoutListener)));
         }
     }
 
diff --git a/src/Symfony/Bundle/SecurityBundle/Tests/Debug/TraceableFirewallListenerTest.php b/src/Symfony/Bundle/SecurityBundle/Tests/Debug/TraceableFirewallListenerTest.php
index 829d1f11e6..c77ed14dc6 100644
--- a/src/Symfony/Bundle/SecurityBundle/Tests/Debug/TraceableFirewallListenerTest.php
+++ b/src/Symfony/Bundle/SecurityBundle/Tests/Debug/TraceableFirewallListenerTest.php
@@ -60,6 +60,6 @@ class TraceableFirewallListenerTest extends TestCase
         $this->assertCount(1, $listeners);
         $this->assertSame($response, $listeners[0]['response']);
         $this->assertInstanceOf(ClassStub::class, $listeners[0]['stub']);
-        $this->assertSame(get_class($listener), (string) $listeners[0]['stub']);
+        $this->assertSame(\get_class($listener), (string) $listeners[0]['stub']);
     }
 }
diff --git a/src/Symfony/Bundle/SecurityBundle/Tests/DependencyInjection/CompleteConfigurationTest.php b/src/Symfony/Bundle/SecurityBundle/Tests/DependencyInjection/CompleteConfigurationTest.php
index 7e5ecd5d9e..a688eb143a 100644
--- a/src/Symfony/Bundle/SecurityBundle/Tests/DependencyInjection/CompleteConfigurationTest.php
+++ b/src/Symfony/Bundle/SecurityBundle/Tests/DependencyInjection/CompleteConfigurationTest.php
@@ -257,7 +257,7 @@ abstract class CompleteConfigurationTest extends TestCase
             $this->assertArrayNotHasKey($matcherId, $matcherIds);
             $matcherIds[$matcherId] = true;
 
-            $i = count($matcherIds);
+            $i = \count($matcherIds);
             if (1 === $i) {
                 $this->assertEquals(array('ROLE_USER'), $attributes);
                 $this->assertEquals('https', $channel);
diff --git a/src/Symfony/Bundle/SecurityBundle/Tests/Functional/MissingUserProviderTest.php b/src/Symfony/Bundle/SecurityBundle/Tests/Functional/MissingUserProviderTest.php
index f66d67a55c..f1efe64928 100644
--- a/src/Symfony/Bundle/SecurityBundle/Tests/Functional/MissingUserProviderTest.php
+++ b/src/Symfony/Bundle/SecurityBundle/Tests/Functional/MissingUserProviderTest.php
@@ -11,8 +11,6 @@
 
 namespace Symfony\Bundle\SecurityBundle\Tests\Functional;
 
-use Symfony\Component\Config\Definition\Exception\InvalidConfigurationException;
-
 class MissingUserProviderTest extends WebTestCase
 {
     /**
diff --git a/src/Symfony/Bundle/SecurityBundle/Tests/Functional/UserPasswordEncoderCommandTest.php b/src/Symfony/Bundle/SecurityBundle/Tests/Functional/UserPasswordEncoderCommandTest.php
index 13d2922c77..4245d07687 100644
--- a/src/Symfony/Bundle/SecurityBundle/Tests/Functional/UserPasswordEncoderCommandTest.php
+++ b/src/Symfony/Bundle/SecurityBundle/Tests/Functional/UserPasswordEncoderCommandTest.php
@@ -231,7 +231,7 @@ EOTXT
 
     protected function setUp()
     {
-        putenv('COLUMNS='.(119 + strlen(PHP_EOL)));
+        putenv('COLUMNS='.(119 + \strlen(PHP_EOL)));
         $kernel = $this->createKernel(array('test_case' => 'PasswordEncode'));
         $kernel->boot();
 
@@ -249,7 +249,7 @@ EOTXT
 
     private function setupArgon2i()
     {
-        putenv('COLUMNS='.(119 + strlen(PHP_EOL)));
+        putenv('COLUMNS='.(119 + \strlen(PHP_EOL)));
         $kernel = $this->createKernel(array('test_case' => 'PasswordEncode', 'root_config' => 'argon2i.yml'));
         $kernel->boot();
 
diff --git a/src/Symfony/Bundle/SecurityBundle/Tests/Functional/WebTestCase.php b/src/Symfony/Bundle/SecurityBundle/Tests/Functional/WebTestCase.php
index bb98a2a065..03e2f3c72c 100644
--- a/src/Symfony/Bundle/SecurityBundle/Tests/Functional/WebTestCase.php
+++ b/src/Symfony/Bundle/SecurityBundle/Tests/Functional/WebTestCase.php
@@ -68,6 +68,6 @@ class WebTestCase extends BaseWebTestCase
 
     protected static function getVarDir()
     {
-        return 'SB'.substr(strrchr(get_called_class(), '\\'), 1);
+        return 'SB'.substr(strrchr(\get_called_class(), '\\'), 1);
     }
 }
diff --git a/src/Symfony/Bundle/SecurityBundle/Tests/SecurityUserValueResolverTest.php b/src/Symfony/Bundle/SecurityBundle/Tests/SecurityUserValueResolverTest.php
index a8f005b2e4..d26708ae08 100644
--- a/src/Symfony/Bundle/SecurityBundle/Tests/SecurityUserValueResolverTest.php
+++ b/src/Symfony/Bundle/SecurityBundle/Tests/SecurityUserValueResolverTest.php
@@ -43,7 +43,7 @@ class SecurityUserValueResolverTest extends TestCase
         $tokenStorage->setToken($token);
 
         $resolver = new SecurityUserValueResolver($tokenStorage);
-        $metadata = new ArgumentMetadata('foo', get_class($mock), false, false, null);
+        $metadata = new ArgumentMetadata('foo', \get_class($mock), false, false, null);
 
         $this->assertFalse($resolver->supports(Request::create('/'), $metadata));
     }
diff --git a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExceptionListenerPass.php b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExceptionListenerPass.php
index b7ebb2a406..c370a10658 100644
--- a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExceptionListenerPass.php
+++ b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExceptionListenerPass.php
@@ -32,7 +32,7 @@ class ExceptionListenerPass implements CompilerPassInterface
             $container->removeDefinition('twig.exception_listener');
         } elseif ($container->hasParameter('templating.engines')) {
             $engines = $container->getParameter('templating.engines');
-            if (!in_array('twig', $engines)) {
+            if (!\in_array('twig', $engines)) {
                 $container->removeDefinition('twig.exception_listener');
             }
         }
diff --git a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExtensionPass.php b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExtensionPass.php
index 0ca55f298e..5a107a07c5 100644
--- a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExtensionPass.php
+++ b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/ExtensionPass.php
@@ -44,7 +44,7 @@ class ExtensionPass implements CompilerPassInterface
             $container->getDefinition('twig.extension.form')->addTag('twig.extension');
             $reflClass = new \ReflectionClass('Symfony\Bridge\Twig\Extension\FormExtension');
 
-            $coreThemePath = dirname(dirname($reflClass->getFileName())).'/Resources/views/Form';
+            $coreThemePath = \dirname(\dirname($reflClass->getFileName())).'/Resources/views/Form';
             $container->getDefinition('twig.loader.native_filesystem')->addMethodCall('addPath', array($coreThemePath));
 
             $paths = $container->getDefinition('twig.cache_warmer')->getArgument(2);
diff --git a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/TwigEnvironmentPass.php b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/TwigEnvironmentPass.php
index 3529a6f2b1..d73d347510 100644
--- a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/TwigEnvironmentPass.php
+++ b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Compiler/TwigEnvironmentPass.php
@@ -43,7 +43,7 @@ class TwigEnvironmentPass implements CompilerPassInterface
             $methodCall = array('addExtension', array($extension));
             $extensionClass = $container->getDefinition((string) $extension)->getClass();
 
-            if (is_string($extensionClass) && 0 === strpos($extensionClass, 'Symfony\Bridge\Twig\Extension')) {
+            if (\is_string($extensionClass) && 0 === strpos($extensionClass, 'Symfony\Bridge\Twig\Extension')) {
                 $twigBridgeExtensionsMethodCalls[] = $methodCall;
             } else {
                 $othersExtensionsMethodCalls[] = $methodCall;
diff --git a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Configuration.php b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Configuration.php
index 7c7b8b4e59..d924353771 100644
--- a/src/Symfony/Bundle/TwigBundle/DependencyInjection/Configuration.php
+++ b/src/Symfony/Bundle/TwigBundle/DependencyInjection/Configuration.php
@@ -56,7 +56,7 @@ class Configuration implements ConfigurationInterface
                     ->prototype('scalar')->defaultValue('form_div_layout.html.twig')->end()
                     ->example(array('MyBundle::form.html.twig'))
                     ->validate()
-                        ->ifTrue(function ($v) { return !in_array('form_div_layout.html.twig', $v); })
+                        ->ifTrue(function ($v) { return !\in_array('form_div_layout.html.twig', $v); })
                         ->then(function ($v) {
                             return array_merge(array('form_div_layout.html.twig'), $v);
                         })
@@ -78,7 +78,7 @@ class Configuration implements ConfigurationInterface
                     ->prototype('array')
                         ->normalizeKeys(false)
                         ->beforeNormalization()
-                            ->ifTrue(function ($v) { return is_string($v) && 0 === strpos($v, '@'); })
+                            ->ifTrue(function ($v) { return \is_string($v) && 0 === strpos($v, '@'); })
                             ->then(function ($v) {
                                 if (0 === strpos($v, '@@')) {
                                     return substr($v, 1);
@@ -89,7 +89,7 @@ class Configuration implements ConfigurationInterface
                         ->end()
                         ->beforeNormalization()
                             ->ifTrue(function ($v) {
-                                if (is_array($v)) {
+                                if (\is_array($v)) {
                                     $keys = array_keys($v);
                                     sort($keys);
 
@@ -149,7 +149,7 @@ class Configuration implements ConfigurationInterface
                         ->then(function ($paths) {
                             $normalized = array();
                             foreach ($paths as $path => $namespace) {
-                                if (is_array($namespace)) {
+                                if (\is_array($namespace)) {
                                     // xml
                                     $path = $namespace['value'];
                                     $namespace = $namespace['namespace'];
diff --git a/src/Symfony/Bundle/TwigBundle/DependencyInjection/TwigExtension.php b/src/Symfony/Bundle/TwigBundle/DependencyInjection/TwigExtension.php
index 7e2dbc3ebd..d1644bd5e3 100644
--- a/src/Symfony/Bundle/TwigBundle/DependencyInjection/TwigExtension.php
+++ b/src/Symfony/Bundle/TwigBundle/DependencyInjection/TwigExtension.php
@@ -55,7 +55,7 @@ class TwigExtension extends Extension
         foreach ($configs as $key => $config) {
             if (isset($config['globals'])) {
                 foreach ($config['globals'] as $name => $value) {
-                    if (is_array($value) && isset($value['key'])) {
+                    if (\is_array($value) && isset($value['key'])) {
                         $configs[$key]['globals'][$name] = array(
                             'key' => $name,
                             'value' => $value,
diff --git a/src/Symfony/Bundle/TwigBundle/Tests/DependencyInjection/TwigExtensionTest.php b/src/Symfony/Bundle/TwigBundle/Tests/DependencyInjection/TwigExtensionTest.php
index ca0e2387fd..72d37398bd 100644
--- a/src/Symfony/Bundle/TwigBundle/Tests/DependencyInjection/TwigExtensionTest.php
+++ b/src/Symfony/Bundle/TwigBundle/Tests/DependencyInjection/TwigExtensionTest.php
@@ -74,7 +74,7 @@ class TwigExtensionTest extends TestCase
         $this->assertEquals(3.14, $calls[4][1][1], '->load() registers variables as Twig globals');
 
         // Yaml and Php specific configs
-        if (in_array($format, array('yml', 'php'))) {
+        if (\in_array($format, array('yml', 'php'))) {
             $this->assertEquals('bad', $calls[5][1][0], '->load() registers variables as Twig globals');
             $this->assertEquals(array('key' => 'foo'), $calls[5][1][1], '->load() registers variables as Twig globals');
         }
@@ -160,7 +160,7 @@ class TwigExtensionTest extends TestCase
         $this->compileContainer($container);
 
         $calls = $container->getDefinition('twig')->getMethodCalls();
-        foreach (array_slice($calls, 2) as $call) {
+        foreach (\array_slice($calls, 2) as $call) {
             $this->assertEquals(key($globals), $call[1][0]);
             $this->assertSame(current($globals), $call[1][1]);
 
diff --git a/src/Symfony/Bundle/WebProfilerBundle/Csp/ContentSecurityPolicyHandler.php b/src/Symfony/Bundle/WebProfilerBundle/Csp/ContentSecurityPolicyHandler.php
index 639ee5ca6b..df4458474b 100644
--- a/src/Symfony/Bundle/WebProfilerBundle/Csp/ContentSecurityPolicyHandler.php
+++ b/src/Symfony/Bundle/WebProfilerBundle/Csp/ContentSecurityPolicyHandler.php
@@ -141,7 +141,7 @@ class ContentSecurityPolicyHandler
                     }
                 }
                 $ruleIsSet = true;
-                if (!in_array('\'unsafe-inline\'', $headers[$header][$type], true)) {
+                if (!\in_array('\'unsafe-inline\'', $headers[$header][$type], true)) {
                     $headers[$header][$type][] = '\'unsafe-inline\'';
                 }
                 $headers[$header][$type][] = sprintf('\'nonce-%s\'', $nonces[$tokenName]);
@@ -196,7 +196,7 @@ class ContentSecurityPolicyHandler
 
         foreach (explode(';', $header) as $directive) {
             $parts = explode(' ', trim($directive));
-            if (count($parts) < 1) {
+            if (\count($parts) < 1) {
                 continue;
             }
             $name = array_shift($parts);
@@ -224,7 +224,7 @@ class ContentSecurityPolicyHandler
             return false;
         }
 
-        return in_array('\'unsafe-inline\'', $directives, true) && !$this->hasHashOrNonce($directives);
+        return \in_array('\'unsafe-inline\'', $directives, true) && !$this->hasHashOrNonce($directives);
     }
 
     private function hasHashOrNonce(array $directives)
@@ -236,7 +236,7 @@ class ContentSecurityPolicyHandler
             if ('\'nonce-' === substr($directive, 0, 7)) {
                 return true;
             }
-            if (in_array(substr($directive, 0, 8), array('\'sha256-', '\'sha384-', '\'sha512-'), true)) {
+            if (\in_array(substr($directive, 0, 8), array('\'sha256-', '\'sha384-', '\'sha512-'), true)) {
                 return true;
             }
         }
diff --git a/src/Symfony/Bundle/WebProfilerBundle/EventListener/WebDebugToolbarListener.php b/src/Symfony/Bundle/WebProfilerBundle/EventListener/WebDebugToolbarListener.php
index 490e16382f..119ab0c9c2 100644
--- a/src/Symfony/Bundle/WebProfilerBundle/EventListener/WebDebugToolbarListener.php
+++ b/src/Symfony/Bundle/WebProfilerBundle/EventListener/WebDebugToolbarListener.php
@@ -70,7 +70,7 @@ class WebDebugToolbarListener implements EventSubscriberInterface
                     $this->urlGenerator->generate('_profiler', array('token' => $response->headers->get('X-Debug-Token')), UrlGeneratorInterface::ABSOLUTE_URL)
                 );
             } catch (\Exception $e) {
-                $response->headers->set('X-Debug-Error', get_class($e).': '.preg_replace('/\s+/', ' ', $e->getMessage()));
+                $response->headers->set('X-Debug-Error', \get_class($e).': '.preg_replace('/\s+/', ' ', $e->getMessage()));
             }
         }
 
diff --git a/src/Symfony/Bundle/WebProfilerBundle/Tests/DependencyInjection/WebProfilerExtensionTest.php b/src/Symfony/Bundle/WebProfilerBundle/Tests/DependencyInjection/WebProfilerExtensionTest.php
index 43f33dc11f..4dbef86e1d 100644
--- a/src/Symfony/Bundle/WebProfilerBundle/Tests/DependencyInjection/WebProfilerExtensionTest.php
+++ b/src/Symfony/Bundle/WebProfilerBundle/Tests/DependencyInjection/WebProfilerExtensionTest.php
@@ -33,7 +33,7 @@ class WebProfilerExtensionTest extends TestCase
         $errors = array();
         $knownPrivates[] = 'debug.file_link_formatter.url_format';
         foreach ($container->getServiceIds() as $id) {
-            if (in_array($id, $knownPrivates, true)) { // for BC with 3.4
+            if (\in_array($id, $knownPrivates, true)) { // for BC with 3.4
                 continue;
             }
             try {
diff --git a/src/Symfony/Bundle/WebServerBundle/Command/ServerStartCommand.php b/src/Symfony/Bundle/WebServerBundle/Command/ServerStartCommand.php
index 49e3870119..14647d9e7b 100644
--- a/src/Symfony/Bundle/WebServerBundle/Command/ServerStartCommand.php
+++ b/src/Symfony/Bundle/WebServerBundle/Command/ServerStartCommand.php
@@ -90,7 +90,7 @@ EOF
     {
         $io = new SymfonyStyle($input, $output instanceof ConsoleOutputInterface ? $output->getErrorOutput() : $output);
 
-        if (!extension_loaded('pcntl')) {
+        if (!\extension_loaded('pcntl')) {
             $io->error(array(
                 'This command needs the pcntl extension to run.',
                 'You can either install it or use the "server:run" command instead.',
diff --git a/src/Symfony/Bundle/WebServerBundle/WebServer.php b/src/Symfony/Bundle/WebServerBundle/WebServer.php
index beb5190b72..04c442fb34 100644
--- a/src/Symfony/Bundle/WebServerBundle/WebServer.php
+++ b/src/Symfony/Bundle/WebServerBundle/WebServer.php
@@ -154,7 +154,7 @@ class WebServer
         $process->setWorkingDirectory($config->getDocumentRoot());
         $process->setTimeout(null);
 
-        if (in_array('APP_ENV', explode(',', getenv('SYMFONY_DOTENV_VARS')))) {
+        if (\in_array('APP_ENV', explode(',', getenv('SYMFONY_DOTENV_VARS')))) {
             $process->setEnv(array('APP_ENV' => false));
             $process->inheritEnvironmentVariables();
         }
diff --git a/src/Symfony/Component/Asset/UrlPackage.php b/src/Symfony/Component/Asset/UrlPackage.php
index 782b2ddfce..56850330fa 100644
--- a/src/Symfony/Component/Asset/UrlPackage.php
+++ b/src/Symfony/Component/Asset/UrlPackage.php
@@ -47,7 +47,7 @@ class UrlPackage extends Package
     {
         parent::__construct($versionStrategy, $context);
 
-        if (!is_array($baseUrls)) {
+        if (!\is_array($baseUrls)) {
             $baseUrls = (array) $baseUrls;
         }
 
@@ -101,7 +101,7 @@ class UrlPackage extends Package
      */
     public function getBaseUrl($path)
     {
-        if (1 === count($this->baseUrls)) {
+        if (1 === \count($this->baseUrls)) {
             return $this->baseUrls[0];
         }
 
@@ -120,7 +120,7 @@ class UrlPackage extends Package
      */
     protected function chooseBaseUrl($path)
     {
-        return (int) fmod(hexdec(substr(hash('sha256', $path), 0, 10)), count($this->baseUrls));
+        return (int) fmod(hexdec(substr(hash('sha256', $path), 0, 10)), \count($this->baseUrls));
     }
 
     private function getSslUrls($urls)
diff --git a/src/Symfony/Component/BrowserKit/Client.php b/src/Symfony/Component/BrowserKit/Client.php
index e1630a332d..2c198c23c6 100644
--- a/src/Symfony/Component/BrowserKit/Client.php
+++ b/src/Symfony/Component/BrowserKit/Client.php
@@ -439,7 +439,7 @@ abstract class Client
             unlink($deprecationsFile);
             foreach ($deprecations ? unserialize($deprecations) : array() as $deprecation) {
                 if ($deprecation[0]) {
-                    trigger_error($deprecation[1], E_USER_DEPRECATED);
+                    @trigger_error($deprecation[1], E_USER_DEPRECATED);
                 } else {
                     @trigger_error($deprecation[1], E_USER_DEPRECATED);
                 }
@@ -581,7 +581,7 @@ abstract class Client
 
         $request = $this->internalRequest;
 
-        if (in_array($this->internalResponse->getStatus(), array(301, 302, 303))) {
+        if (\in_array($this->internalResponse->getStatus(), array(301, 302, 303))) {
             $method = 'GET';
             $files = array();
             $content = null;
diff --git a/src/Symfony/Component/BrowserKit/Cookie.php b/src/Symfony/Component/BrowserKit/Cookie.php
index 480f02b948..0fd530af8b 100644
--- a/src/Symfony/Component/BrowserKit/Cookie.php
+++ b/src/Symfony/Component/BrowserKit/Cookie.php
@@ -169,7 +169,7 @@ class Cookie
                 continue;
             }
 
-            if (2 === count($elements = explode('=', $part, 2))) {
+            if (2 === \count($elements = explode('=', $part, 2))) {
                 if ('expires' === strtolower($elements[0])) {
                     $elements[1] = self::parseDate($elements[1]);
                 }
@@ -193,7 +193,7 @@ class Cookie
     private static function parseDate($dateValue)
     {
         // trim single quotes around date if present
-        if (($length = strlen($dateValue)) > 1 && "'" === $dateValue[0] && "'" === $dateValue[$length - 1]) {
+        if (($length = \strlen($dateValue)) > 1 && "'" === $dateValue[0] && "'" === $dateValue[$length - 1]) {
             $dateValue = substr($dateValue, 1, -1);
         }
 
diff --git a/src/Symfony/Component/BrowserKit/CookieJar.php b/src/Symfony/Component/BrowserKit/CookieJar.php
index 7a4d64c10e..24eb9abedd 100644
--- a/src/Symfony/Component/BrowserKit/CookieJar.php
+++ b/src/Symfony/Component/BrowserKit/CookieJar.php
@@ -123,7 +123,7 @@ class CookieJar
                 if (0 === $i || preg_match('/^(?P<token>\s*[0-9A-Za-z!#\$%\&\'\*\+\-\.^_`\|~]+)=/', $part)) {
                     $cookies[] = ltrim($part);
                 } else {
-                    $cookies[count($cookies) - 1] .= ','.$part;
+                    $cookies[\count($cookies) - 1] .= ','.$part;
                 }
             }
         }
@@ -186,13 +186,13 @@ class CookieJar
         foreach ($this->cookieJar as $domain => $pathCookies) {
             if ($domain) {
                 $domain = '.'.ltrim($domain, '.');
-                if ($domain != substr('.'.$parts['host'], -strlen($domain))) {
+                if ($domain != substr('.'.$parts['host'], -\strlen($domain))) {
                     continue;
                 }
             }
 
             foreach ($pathCookies as $path => $namedCookies) {
-                if ($path != substr($parts['path'], 0, strlen($path))) {
+                if ($path != substr($parts['path'], 0, \strlen($path))) {
                     continue;
                 }
 
diff --git a/src/Symfony/Component/BrowserKit/History.php b/src/Symfony/Component/BrowserKit/History.php
index aeca327734..beec17c6b4 100644
--- a/src/Symfony/Component/BrowserKit/History.php
+++ b/src/Symfony/Component/BrowserKit/History.php
@@ -35,9 +35,9 @@ class History
      */
     public function add(Request $request)
     {
-        $this->stack = array_slice($this->stack, 0, $this->position + 1);
+        $this->stack = \array_slice($this->stack, 0, $this->position + 1);
         $this->stack[] = clone $request;
-        $this->position = count($this->stack) - 1;
+        $this->position = \count($this->stack) - 1;
     }
 
     /**
@@ -47,7 +47,7 @@ class History
      */
     public function isEmpty()
     {
-        return 0 == count($this->stack);
+        return 0 == \count($this->stack);
     }
 
     /**
@@ -75,7 +75,7 @@ class History
      */
     public function forward()
     {
-        if ($this->position > count($this->stack) - 2) {
+        if ($this->position > \count($this->stack) - 2) {
             throw new \LogicException('You are already on the last page.');
         }
 
diff --git a/src/Symfony/Component/BrowserKit/Response.php b/src/Symfony/Component/BrowserKit/Response.php
index 16b2f5bcfe..6c50aeee43 100644
--- a/src/Symfony/Component/BrowserKit/Response.php
+++ b/src/Symfony/Component/BrowserKit/Response.php
@@ -44,7 +44,7 @@ class Response
     {
         $headers = '';
         foreach ($this->headers as $name => $value) {
-            if (is_string($value)) {
+            if (\is_string($value)) {
                 $headers .= $this->buildHeader($name, $value);
             } else {
                 foreach ($value as $headerValue) {
@@ -113,10 +113,10 @@ class Response
         foreach ($this->headers as $key => $value) {
             if (str_replace('-', '_', strtolower($key)) === $normalizedHeader) {
                 if ($first) {
-                    return is_array($value) ? (count($value) ? $value[0] : '') : $value;
+                    return \is_array($value) ? (\count($value) ? $value[0] : '') : $value;
                 }
 
-                return is_array($value) ? $value : array($value);
+                return \is_array($value) ? $value : array($value);
             }
         }
 
diff --git a/src/Symfony/Component/Cache/Adapter/AbstractAdapter.php b/src/Symfony/Component/Cache/Adapter/AbstractAdapter.php
index 2f148e63d2..d437d63f3a 100644
--- a/src/Symfony/Component/Cache/Adapter/AbstractAdapter.php
+++ b/src/Symfony/Component/Cache/Adapter/AbstractAdapter.php
@@ -39,8 +39,8 @@ abstract class AbstractAdapter implements AdapterInterface, CacheInterface, Logg
     protected function __construct(string $namespace = '', int $defaultLifetime = 0)
     {
         $this->namespace = '' === $namespace ? '' : CacheItem::validateKey($namespace).':';
-        if (null !== $this->maxIdLength && strlen($namespace) > $this->maxIdLength - 24) {
-            throw new InvalidArgumentException(sprintf('Namespace must be %d chars max, %d given ("%s")', $this->maxIdLength - 24, strlen($namespace), $namespace));
+        if (null !== $this->maxIdLength && \strlen($namespace) > $this->maxIdLength - 24) {
+            throw new InvalidArgumentException(sprintf('Namespace must be %d chars max, %d given ("%s")', $this->maxIdLength - 24, \strlen($namespace), $namespace));
         }
         $this->createCacheItem = \Closure::bind(
             function ($key, $value, $isHit) use ($defaultLifetime) {
@@ -144,8 +144,8 @@ abstract class AbstractAdapter implements AdapterInterface, CacheInterface, Logg
 
     public static function createConnection($dsn, array $options = array())
     {
-        if (!is_string($dsn)) {
-            throw new InvalidArgumentException(sprintf('The %s() method expect argument #1 to be string, %s given.', __METHOD__, gettype($dsn)));
+        if (!\is_string($dsn)) {
+            throw new InvalidArgumentException(sprintf('The %s() method expect argument #1 to be string, %s given.', __METHOD__, \gettype($dsn)));
         }
         if (0 === strpos($dsn, 'redis://')) {
             return RedisAdapter::createConnection($dsn, $options);
@@ -254,11 +254,11 @@ abstract class AbstractAdapter implements AdapterInterface, CacheInterface, Logg
                 continue;
             }
             if (\is_array($e) || 1 === \count($values)) {
-                foreach (is_array($e) ? $e : array_keys($values) as $id) {
+                foreach (\is_array($e) ? $e : array_keys($values) as $id) {
                     $ok = false;
                     $v = $values[$id];
-                    $type = is_object($v) ? get_class($v) : gettype($v);
-                    CacheItem::log($this->logger, 'Failed to save key "{key}" ({type})', array('key' => substr($id, strlen($this->namespace)), 'type' => $type, 'exception' => $e instanceof \Exception ? $e : null));
+                    $type = \is_object($v) ? \get_class($v) : \gettype($v);
+                    CacheItem::log($this->logger, 'Failed to save key "{key}" ({type})', array('key' => substr($id, \strlen($this->namespace)), 'type' => $type, 'exception' => $e instanceof \Exception ? $e : null));
                 }
             } else {
                 foreach ($values as $id => $v) {
@@ -279,8 +279,8 @@ abstract class AbstractAdapter implements AdapterInterface, CacheInterface, Logg
                     continue;
                 }
                 $ok = false;
-                $type = is_object($v) ? get_class($v) : gettype($v);
-                CacheItem::log($this->logger, 'Failed to save key "{key}" ({type})', array('key' => substr($id, strlen($this->namespace)), 'type' => $type, 'exception' => $e instanceof \Exception ? $e : null));
+                $type = \is_object($v) ? \get_class($v) : \gettype($v);
+                CacheItem::log($this->logger, 'Failed to save key "{key}" ({type})', array('key' => substr($id, \strlen($this->namespace)), 'type' => $type, 'exception' => $e instanceof \Exception ? $e : null));
             }
         }
 
diff --git a/src/Symfony/Component/Cache/Adapter/ChainAdapter.php b/src/Symfony/Component/Cache/Adapter/ChainAdapter.php
index 8b737d43f7..1b0a9011ec 100644
--- a/src/Symfony/Component/Cache/Adapter/ChainAdapter.php
+++ b/src/Symfony/Component/Cache/Adapter/ChainAdapter.php
@@ -49,7 +49,7 @@ class ChainAdapter implements AdapterInterface, CacheInterface, PruneableInterfa
 
         foreach ($adapters as $adapter) {
             if (!$adapter instanceof CacheItemPoolInterface) {
-                throw new InvalidArgumentException(sprintf('The class "%s" does not implement the "%s" interface.', get_class($adapter), CacheItemPoolInterface::class));
+                throw new InvalidArgumentException(sprintf('The class "%s" does not implement the "%s" interface.', \get_class($adapter), CacheItemPoolInterface::class));
             }
 
             if ($adapter instanceof AdapterInterface) {
@@ -58,7 +58,7 @@ class ChainAdapter implements AdapterInterface, CacheInterface, PruneableInterfa
                 $this->adapters[] = new ProxyAdapter($adapter);
             }
         }
-        $this->adapterCount = count($this->adapters);
+        $this->adapterCount = \count($this->adapters);
 
         $this->syncItem = \Closure::bind(
             function ($sourceItem, $item) use ($defaultLifetime) {
diff --git a/src/Symfony/Component/Cache/Adapter/PhpArrayAdapter.php b/src/Symfony/Component/Cache/Adapter/PhpArrayAdapter.php
index 3a698f0a78..8fedc0422c 100644
--- a/src/Symfony/Component/Cache/Adapter/PhpArrayAdapter.php
+++ b/src/Symfony/Component/Cache/Adapter/PhpArrayAdapter.php
@@ -123,7 +123,7 @@ class PhpArrayAdapter implements AdapterInterface, CacheInterface, PruneableInte
     public function getItem($key)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -165,7 +165,7 @@ class PhpArrayAdapter implements AdapterInterface, CacheInterface, PruneableInte
     {
         foreach ($keys as $key) {
             if (!\is_string($key)) {
-                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
             }
         }
         if (null === $this->values) {
@@ -181,7 +181,7 @@ class PhpArrayAdapter implements AdapterInterface, CacheInterface, PruneableInte
     public function hasItem($key)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -196,7 +196,7 @@ class PhpArrayAdapter implements AdapterInterface, CacheInterface, PruneableInte
     public function deleteItem($key)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -215,7 +215,7 @@ class PhpArrayAdapter implements AdapterInterface, CacheInterface, PruneableInte
 
         foreach ($keys as $key) {
             if (!\is_string($key)) {
-                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
             }
 
             if (isset($this->keys[$key])) {
diff --git a/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php b/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php
index 007f1fe2c0..ff86f51805 100644
--- a/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php
+++ b/src/Symfony/Component/Cache/Adapter/ProxyAdapter.php
@@ -39,7 +39,7 @@ class ProxyAdapter implements AdapterInterface, CacheInterface, PruneableInterfa
         $this->pool = $pool;
         $this->poolHash = $poolHash = spl_object_hash($pool);
         $this->namespace = '' === $namespace ? '' : CacheItem::validateKey($namespace);
-        $this->namespaceLen = strlen($namespace);
+        $this->namespaceLen = \strlen($namespace);
         $this->createCacheItem = \Closure::bind(
             function ($key, $innerItem) use ($defaultLifetime, $poolHash) {
                 $item = new CacheItem();
diff --git a/src/Symfony/Component/Cache/Adapter/TraceableAdapter.php b/src/Symfony/Component/Cache/Adapter/TraceableAdapter.php
index 5ccbdb00ba..2bd10b5ca5 100644
--- a/src/Symfony/Component/Cache/Adapter/TraceableAdapter.php
+++ b/src/Symfony/Component/Cache/Adapter/TraceableAdapter.php
@@ -41,7 +41,7 @@ class TraceableAdapter implements AdapterInterface, CacheInterface, PruneableInt
     public function get(string $key, callable $callback, float $beta = null)
     {
         if (!$this->pool instanceof CacheInterface) {
-            throw new \BadMethodCallException(sprintf('Cannot call "%s::get()": this class doesn\'t implement "%s".', get_class($this->pool), CacheInterface::class));
+            throw new \BadMethodCallException(sprintf('Cannot call "%s::get()": this class doesn\'t implement "%s".', \get_class($this->pool), CacheInterface::class));
         }
 
         $isHit = true;
@@ -54,7 +54,7 @@ class TraceableAdapter implements AdapterInterface, CacheInterface, PruneableInt
         $event = $this->start(__FUNCTION__);
         try {
             $value = $this->pool->get($key, $callback, $beta);
-            $event->result[$key] = \is_object($value) ? \get_class($value) : gettype($value);
+            $event->result[$key] = \is_object($value) ? \get_class($value) : \gettype($value);
         } finally {
             $event->end = microtime(true);
         }
diff --git a/src/Symfony/Component/Cache/CacheItem.php b/src/Symfony/Component/Cache/CacheItem.php
index 659cbdcab2..4ded2227c2 100644
--- a/src/Symfony/Component/Cache/CacheItem.php
+++ b/src/Symfony/Component/Cache/CacheItem.php
@@ -93,7 +93,7 @@ final class CacheItem implements CacheItemInterface
         } elseif ($expiration instanceof \DateTimeInterface) {
             $this->expiry = (float) $expiration->format('U.u');
         } else {
-            throw new InvalidArgumentException(sprintf('Expiration date must implement DateTimeInterface or be null, "%s" given', is_object($expiration) ? get_class($expiration) : gettype($expiration)));
+            throw new InvalidArgumentException(sprintf('Expiration date must implement DateTimeInterface or be null, "%s" given', \is_object($expiration) ? \get_class($expiration) : \gettype($expiration)));
         }
 
         return $this;
@@ -111,7 +111,7 @@ final class CacheItem implements CacheItemInterface
         } elseif (\is_int($time)) {
             $this->expiry = $time + microtime(true);
         } else {
-            throw new InvalidArgumentException(sprintf('Expiration date must be an integer, a DateInterval or null, "%s" given', is_object($time) ? get_class($time) : gettype($time)));
+            throw new InvalidArgumentException(sprintf('Expiration date must be an integer, a DateInterval or null, "%s" given', \is_object($time) ? \get_class($time) : \gettype($time)));
         }
 
         return $this;
@@ -136,7 +136,7 @@ final class CacheItem implements CacheItemInterface
         }
         foreach ($tags as $tag) {
             if (!\is_string($tag)) {
-                throw new InvalidArgumentException(sprintf('Cache tag must be string, "%s" given', is_object($tag) ? get_class($tag) : gettype($tag)));
+                throw new InvalidArgumentException(sprintf('Cache tag must be string, "%s" given', \is_object($tag) ? \get_class($tag) : \gettype($tag)));
             }
             if (isset($this->newMetadata[self::METADATA_TAGS][$tag])) {
                 continue;
@@ -189,7 +189,7 @@ final class CacheItem implements CacheItemInterface
     public static function validateKey($key)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if ('' === $key) {
             throw new InvalidArgumentException('Cache key length must be greater than zero');
diff --git a/src/Symfony/Component/Cache/Simple/AbstractCache.php b/src/Symfony/Component/Cache/Simple/AbstractCache.php
index d708496337..b154fad118 100644
--- a/src/Symfony/Component/Cache/Simple/AbstractCache.php
+++ b/src/Symfony/Component/Cache/Simple/AbstractCache.php
@@ -35,8 +35,8 @@ abstract class AbstractCache implements CacheInterface, LoggerAwareInterface, Re
     {
         $this->defaultLifetime = max(0, $defaultLifetime);
         $this->namespace = '' === $namespace ? '' : CacheItem::validateKey($namespace).':';
-        if (null !== $this->maxIdLength && strlen($namespace) > $this->maxIdLength - 24) {
-            throw new InvalidArgumentException(sprintf('Namespace must be %d chars max, %d given ("%s")', $this->maxIdLength - 24, strlen($namespace), $namespace));
+        if (null !== $this->maxIdLength && \strlen($namespace) > $this->maxIdLength - 24) {
+            throw new InvalidArgumentException(sprintf('Namespace must be %d chars max, %d given ("%s")', $this->maxIdLength - 24, \strlen($namespace), $namespace));
         }
     }
 
@@ -76,7 +76,7 @@ abstract class AbstractCache implements CacheInterface, LoggerAwareInterface, Re
         if ($keys instanceof \Traversable) {
             $keys = iterator_to_array($keys, false);
         } elseif (!\is_array($keys)) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
         $ids = array();
 
@@ -100,7 +100,7 @@ abstract class AbstractCache implements CacheInterface, LoggerAwareInterface, Re
     public function setMultiple($values, $ttl = null)
     {
         if (!\is_array($values) && !$values instanceof \Traversable) {
-            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', is_object($values) ? get_class($values) : gettype($values)));
+            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', \is_object($values) ? \get_class($values) : \gettype($values)));
         }
         $valuesById = array();
 
@@ -123,7 +123,7 @@ abstract class AbstractCache implements CacheInterface, LoggerAwareInterface, Re
         }
         $keys = array();
         foreach (\is_array($e) ? $e : array_keys($valuesById) as $id) {
-            $keys[] = substr($id, strlen($this->namespace));
+            $keys[] = substr($id, \strlen($this->namespace));
         }
         CacheItem::log($this->logger, 'Failed to save values', array('keys' => $keys, 'exception' => $e instanceof \Exception ? $e : null));
 
@@ -138,7 +138,7 @@ abstract class AbstractCache implements CacheInterface, LoggerAwareInterface, Re
         if ($keys instanceof \Traversable) {
             $keys = iterator_to_array($keys, false);
         } elseif (!\is_array($keys)) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
 
         return $this->deleteItems($keys);
@@ -156,7 +156,7 @@ abstract class AbstractCache implements CacheInterface, LoggerAwareInterface, Re
             return 0 < $ttl ? $ttl : false;
         }
 
-        throw new InvalidArgumentException(sprintf('Expiration date must be an integer, a DateInterval or null, "%s" given', is_object($ttl) ? get_class($ttl) : gettype($ttl)));
+        throw new InvalidArgumentException(sprintf('Expiration date must be an integer, a DateInterval or null, "%s" given', \is_object($ttl) ? \get_class($ttl) : \gettype($ttl)));
     }
 
     private function generateValues($values, &$keys, $default)
diff --git a/src/Symfony/Component/Cache/Simple/ArrayCache.php b/src/Symfony/Component/Cache/Simple/ArrayCache.php
index 14f35bd6a9..9185e5fa55 100644
--- a/src/Symfony/Component/Cache/Simple/ArrayCache.php
+++ b/src/Symfony/Component/Cache/Simple/ArrayCache.php
@@ -69,7 +69,7 @@ class ArrayCache implements CacheInterface, LoggerAwareInterface, ResettableInte
         if ($keys instanceof \Traversable) {
             $keys = iterator_to_array($keys, false);
         } elseif (!\is_array($keys)) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
         foreach ($keys as $key) {
             if (!\is_string($key) || !isset($this->expiries[$key])) {
@@ -86,7 +86,7 @@ class ArrayCache implements CacheInterface, LoggerAwareInterface, ResettableInte
     public function deleteMultiple($keys)
     {
         if (!\is_array($keys) && !$keys instanceof \Traversable) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
         foreach ($keys as $key) {
             $this->delete($key);
@@ -113,7 +113,7 @@ class ArrayCache implements CacheInterface, LoggerAwareInterface, ResettableInte
     public function setMultiple($values, $ttl = null)
     {
         if (!\is_array($values) && !$values instanceof \Traversable) {
-            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', is_object($values) ? get_class($values) : gettype($values)));
+            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', \is_object($values) ? \get_class($values) : \gettype($values)));
         }
         $valuesArray = array();
 
@@ -151,6 +151,6 @@ class ArrayCache implements CacheInterface, LoggerAwareInterface, ResettableInte
             return 0 < $ttl ? $ttl : false;
         }
 
-        throw new InvalidArgumentException(sprintf('Expiration date must be an integer, a DateInterval or null, "%s" given', is_object($ttl) ? get_class($ttl) : gettype($ttl)));
+        throw new InvalidArgumentException(sprintf('Expiration date must be an integer, a DateInterval or null, "%s" given', \is_object($ttl) ? \get_class($ttl) : \gettype($ttl)));
     }
 }
diff --git a/src/Symfony/Component/Cache/Simple/ChainCache.php b/src/Symfony/Component/Cache/Simple/ChainCache.php
index d3d575a661..922d0fff31 100644
--- a/src/Symfony/Component/Cache/Simple/ChainCache.php
+++ b/src/Symfony/Component/Cache/Simple/ChainCache.php
@@ -44,13 +44,13 @@ class ChainCache implements CacheInterface, PruneableInterface, ResettableInterf
 
         foreach ($caches as $cache) {
             if (!$cache instanceof CacheInterface) {
-                throw new InvalidArgumentException(sprintf('The class "%s" does not implement the "%s" interface.', get_class($cache), CacheInterface::class));
+                throw new InvalidArgumentException(sprintf('The class "%s" does not implement the "%s" interface.', \get_class($cache), CacheInterface::class));
             }
         }
 
         $this->miss = new \stdClass();
         $this->caches = array_values($caches);
-        $this->cacheCount = count($this->caches);
+        $this->cacheCount = \count($this->caches);
         $this->defaultLifetime = 0 < $defaultLifetime ? $defaultLifetime : null;
     }
 
diff --git a/src/Symfony/Component/Cache/Simple/PhpArrayCache.php b/src/Symfony/Component/Cache/Simple/PhpArrayCache.php
index aeef4668ae..fbb0afcc0a 100644
--- a/src/Symfony/Component/Cache/Simple/PhpArrayCache.php
+++ b/src/Symfony/Component/Cache/Simple/PhpArrayCache.php
@@ -64,7 +64,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
     public function get($key, $default = null)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -103,11 +103,11 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
         if ($keys instanceof \Traversable) {
             $keys = iterator_to_array($keys, false);
         } elseif (!\is_array($keys)) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
         foreach ($keys as $key) {
             if (!\is_string($key)) {
-                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
             }
         }
         if (null === $this->values) {
@@ -123,7 +123,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
     public function has($key)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -138,7 +138,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
     public function delete($key)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -153,7 +153,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
     public function deleteMultiple($keys)
     {
         if (!\is_array($keys) && !$keys instanceof \Traversable) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
 
         $deleted = true;
@@ -161,7 +161,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
 
         foreach ($keys as $key) {
             if (!\is_string($key)) {
-                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
             }
 
             if (isset($this->keys[$key])) {
@@ -187,7 +187,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
     public function set($key, $value, $ttl = null)
     {
         if (!\is_string($key)) {
-            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+            throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
         }
         if (null === $this->values) {
             $this->initialize();
@@ -202,7 +202,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
     public function setMultiple($values, $ttl = null)
     {
         if (!\is_array($values) && !$values instanceof \Traversable) {
-            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', is_object($values) ? get_class($values) : gettype($values)));
+            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', \is_object($values) ? \get_class($values) : \gettype($values)));
         }
 
         $saved = true;
@@ -210,7 +210,7 @@ class PhpArrayCache implements CacheInterface, PruneableInterface, ResettableInt
 
         foreach ($values as $key => $value) {
             if (!\is_string($key) && !\is_int($key)) {
-                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', is_object($key) ? get_class($key) : gettype($key)));
+                throw new InvalidArgumentException(sprintf('Cache key must be string, "%s" given.', \is_object($key) ? \get_class($key) : \gettype($key)));
             }
 
             if (isset($this->keys[$key])) {
diff --git a/src/Symfony/Component/Cache/Simple/Psr6Cache.php b/src/Symfony/Component/Cache/Simple/Psr6Cache.php
index 4a71346d2c..1a601621bb 100644
--- a/src/Symfony/Component/Cache/Simple/Psr6Cache.php
+++ b/src/Symfony/Component/Cache/Simple/Psr6Cache.php
@@ -122,7 +122,7 @@ class Psr6Cache implements CacheInterface, PruneableInterface, ResettableInterfa
         if ($keys instanceof \Traversable) {
             $keys = iterator_to_array($keys, false);
         } elseif (!\is_array($keys)) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
 
         try {
@@ -148,7 +148,7 @@ class Psr6Cache implements CacheInterface, PruneableInterface, ResettableInterfa
     {
         $valuesIsArray = \is_array($values);
         if (!$valuesIsArray && !$values instanceof \Traversable) {
-            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', is_object($values) ? get_class($values) : gettype($values)));
+            throw new InvalidArgumentException(sprintf('Cache values must be array or Traversable, "%s" given', \is_object($values) ? \get_class($values) : \gettype($values)));
         }
         $items = array();
 
@@ -200,7 +200,7 @@ class Psr6Cache implements CacheInterface, PruneableInterface, ResettableInterfa
         if ($keys instanceof \Traversable) {
             $keys = iterator_to_array($keys, false);
         } elseif (!\is_array($keys)) {
-            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', is_object($keys) ? get_class($keys) : gettype($keys)));
+            throw new InvalidArgumentException(sprintf('Cache keys must be array or Traversable, "%s" given', \is_object($keys) ? \get_class($keys) : \gettype($keys)));
         }
 
         try {
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/AbstractRedisAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/AbstractRedisAdapterTest.php
index d9353821ae..147dfcd153 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/AbstractRedisAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/AbstractRedisAdapterTest.php
@@ -30,7 +30,7 @@ abstract class AbstractRedisAdapterTest extends AdapterTestCase
 
     public static function setupBeforeClass()
     {
-        if (!extension_loaded('redis')) {
+        if (!\extension_loaded('redis')) {
             self::markTestSkipped('Extension redis required.');
         }
         if (!@((new \Redis())->connect(getenv('REDIS_HOST')))) {
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/ApcuAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/ApcuAdapterTest.php
index 72df12e4b5..29d2970a3b 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/ApcuAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/ApcuAdapterTest.php
@@ -24,7 +24,7 @@ class ApcuAdapterTest extends AdapterTestCase
 
     public function createCachePool($defaultLifetime = 0)
     {
-        if (!function_exists('apcu_fetch') || !ini_get('apc.enabled')) {
+        if (!\function_exists('apcu_fetch') || !ini_get('apc.enabled')) {
             $this->markTestSkipped('APCu extension is required.');
         }
         if ('cli' === PHP_SAPI && !ini_get('apc.enable_cli')) {
@@ -54,7 +54,7 @@ class ApcuAdapterTest extends AdapterTestCase
 
     public function testVersion()
     {
-        $namespace = str_replace('\\', '.', get_class($this));
+        $namespace = str_replace('\\', '.', \get_class($this));
 
         $pool1 = new ApcuAdapter($namespace, 0, 'p1');
 
@@ -79,7 +79,7 @@ class ApcuAdapterTest extends AdapterTestCase
 
     public function testNamespace()
     {
-        $namespace = str_replace('\\', '.', get_class($this));
+        $namespace = str_replace('\\', '.', \get_class($this));
 
         $pool1 = new ApcuAdapter($namespace.'_1', 0, 'p1');
 
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/FilesystemAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/FilesystemAdapterTest.php
index b6757514eb..fa8306826e 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/FilesystemAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/FilesystemAdapterTest.php
@@ -34,7 +34,7 @@ class FilesystemAdapterTest extends AdapterTestCase
         if (!file_exists($dir)) {
             return;
         }
-        if (!$dir || 0 !== strpos(dirname($dir), sys_get_temp_dir())) {
+        if (!$dir || 0 !== strpos(\dirname($dir), sys_get_temp_dir())) {
             throw new \Exception(__METHOD__."() operates only on subdirs of system's temp dir");
         }
         $children = new \RecursiveIteratorIterator(
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/MaxIdLengthAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/MaxIdLengthAdapterTest.php
index f4822e9dfc..7613afa7f9 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/MaxIdLengthAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/MaxIdLengthAdapterTest.php
@@ -47,9 +47,9 @@ class MaxIdLengthAdapterTest extends TestCase
 
         // No versioning enabled
         $this->assertEquals('--------------------------:------------', $reflectionMethod->invokeArgs($cache, array(str_repeat('-', 12))));
-        $this->assertLessThanOrEqual(50, strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 12)))));
-        $this->assertLessThanOrEqual(50, strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 23)))));
-        $this->assertLessThanOrEqual(50, strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 40)))));
+        $this->assertLessThanOrEqual(50, \strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 12)))));
+        $this->assertLessThanOrEqual(50, \strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 23)))));
+        $this->assertLessThanOrEqual(50, \strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 40)))));
 
         $reflectionProperty = $reflectionClass->getProperty('versioningIsEnabled');
         $reflectionProperty->setAccessible(true);
@@ -57,9 +57,9 @@ class MaxIdLengthAdapterTest extends TestCase
 
         // Versioning enabled
         $this->assertEquals('--------------------------:1/------------', $reflectionMethod->invokeArgs($cache, array(str_repeat('-', 12))));
-        $this->assertLessThanOrEqual(50, strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 12)))));
-        $this->assertLessThanOrEqual(50, strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 23)))));
-        $this->assertLessThanOrEqual(50, strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 40)))));
+        $this->assertLessThanOrEqual(50, \strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 12)))));
+        $this->assertLessThanOrEqual(50, \strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 23)))));
+        $this->assertLessThanOrEqual(50, \strlen($reflectionMethod->invokeArgs($cache, array(str_repeat('-', 40)))));
     }
 
     /**
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/PdoAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/PdoAdapterTest.php
index 24e3f9bbc9..b587cf6d62 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/PdoAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/PdoAdapterTest.php
@@ -25,7 +25,7 @@ class PdoAdapterTest extends AdapterTestCase
 
     public static function setupBeforeClass()
     {
-        if (!extension_loaded('pdo_sqlite')) {
+        if (!\extension_loaded('pdo_sqlite')) {
             self::markTestSkipped('Extension pdo_sqlite required.');
         }
 
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/PdoDbalAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/PdoDbalAdapterTest.php
index f585c35524..eea89b7458 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/PdoDbalAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/PdoDbalAdapterTest.php
@@ -26,7 +26,7 @@ class PdoDbalAdapterTest extends AdapterTestCase
 
     public static function setupBeforeClass()
     {
-        if (!extension_loaded('pdo_sqlite')) {
+        if (!\extension_loaded('pdo_sqlite')) {
             self::markTestSkipped('Extension pdo_sqlite required.');
         }
 
diff --git a/src/Symfony/Component/Cache/Tests/Adapter/PhpArrayAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/PhpArrayAdapterTest.php
index 86085b1650..96e63e64e3 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/PhpArrayAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/PhpArrayAdapterTest.php
@@ -146,7 +146,7 @@ class PhpArrayAdapterWrapper extends PhpArrayAdapter
 
     public function save(CacheItemInterface $item)
     {
-        call_user_func(\Closure::bind(function () use ($item) {
+        \call_user_func(\Closure::bind(function () use ($item) {
             $key = $item->getKey();
             $this->keys[$key] = $id = \count($this->values);
             $this->data[$key] = $this->values[$id] = $item->get();
diff --git a/src/Symfony/Component/Cache/Tests/CacheItemTest.php b/src/Symfony/Component/Cache/Tests/CacheItemTest.php
index 2572651290..6049f3ec9b 100644
--- a/src/Symfony/Component/Cache/Tests/CacheItemTest.php
+++ b/src/Symfony/Component/Cache/Tests/CacheItemTest.php
@@ -62,7 +62,7 @@ class CacheItemTest extends TestCase
         $this->assertSame($item, $item->tag('foo'));
         $this->assertSame($item, $item->tag(array('bar', 'baz')));
 
-        call_user_func(\Closure::bind(function () use ($item) {
+        \call_user_func(\Closure::bind(function () use ($item) {
             $this->assertSame(array('foo' => 'foo', 'bar' => 'bar', 'baz' => 'baz'), $item->newMetadata[CacheItem::METADATA_TAGS]);
         }, $this, CacheItem::class));
     }
diff --git a/src/Symfony/Component/Cache/Tests/Marshaller/PhpMarshallerTest.php b/src/Symfony/Component/Cache/Tests/Marshaller/PhpMarshallerTest.php
index 962b5fc107..8b1f65211a 100644
--- a/src/Symfony/Component/Cache/Tests/Marshaller/PhpMarshallerTest.php
+++ b/src/Symfony/Component/Cache/Tests/Marshaller/PhpMarshallerTest.php
@@ -50,23 +50,23 @@ class DoctrineProviderTest extends TestCase
 
     public function provideMarshall()
     {
-        yield ['bool', true, 0];
-        yield ['simple-array', [123, ['abc']], 0];
-        yield ['datetime', \DateTime::createFromFormat('U', 0), 1];
+        yield array('bool', true, 0);
+        yield array('simple-array', array(123, array('abc')), 0);
+        yield array('datetime', \DateTime::createFromFormat('U', 0), 1);
 
         $value = new \ArrayObject();
         $value[0] = 1;
         $value->foo = new \ArrayObject();
         $value[1] = $value;
 
-        yield ['array-object', $value, 3];
+        yield array('array-object', $value, 3);
 
         yield array('array-iterator', new \ArrayIterator(array(123), 1), 1);
         yield array('array-object-custom', new MyArrayObject(array(234)), 1);
 
         $value = new MySerializable();
 
-        yield ['serializable', array($value, $value), 2];
+        yield array('serializable', array($value, $value), 2);
 
         $value = new MyWakeup();
         $value->sub = new MyWakeup();
@@ -74,16 +74,16 @@ class DoctrineProviderTest extends TestCase
         $value->sub->bis = 123;
         $value->sub->baz = 123;
 
-        yield ['wakeup', $value, 2];
+        yield array('wakeup', $value, 2);
 
-        yield ['clone', array(new MyCloneable(), new MyNotCloneable()), 2];
+        yield array('clone', array(new MyCloneable(), new MyNotCloneable()), 2);
 
-        yield ['private', array(new MyPrivateValue(123, 234), new MyPrivateChildValue(123, 234)), 2];
+        yield array('private', array(new MyPrivateValue(123, 234), new MyPrivateChildValue(123, 234)), 2);
 
         $value = new \SplObjectStorage();
         $value[new \stdClass()] = 345;
 
-        yield ['spl-object-storage', $value, 2];
+        yield array('spl-object-storage', $value, 2);
     }
 }
 
diff --git a/src/Symfony/Component/Cache/Tests/Simple/AbstractRedisCacheTest.php b/src/Symfony/Component/Cache/Tests/Simple/AbstractRedisCacheTest.php
index f70f49d5db..3e668fdd12 100644
--- a/src/Symfony/Component/Cache/Tests/Simple/AbstractRedisCacheTest.php
+++ b/src/Symfony/Component/Cache/Tests/Simple/AbstractRedisCacheTest.php
@@ -30,7 +30,7 @@ abstract class AbstractRedisCacheTest extends CacheTestCase
 
     public static function setupBeforeClass()
     {
-        if (!extension_loaded('redis')) {
+        if (!\extension_loaded('redis')) {
             self::markTestSkipped('Extension redis required.');
         }
         if (!@((new \Redis())->connect(getenv('REDIS_HOST')))) {
diff --git a/src/Symfony/Component/Cache/Tests/Simple/ApcuCacheTest.php b/src/Symfony/Component/Cache/Tests/Simple/ApcuCacheTest.php
index 297a41756f..e6ccde3579 100644
--- a/src/Symfony/Component/Cache/Tests/Simple/ApcuCacheTest.php
+++ b/src/Symfony/Component/Cache/Tests/Simple/ApcuCacheTest.php
@@ -23,7 +23,7 @@ class ApcuCacheTest extends CacheTestCase
 
     public function createSimpleCache($defaultLifetime = 0)
     {
-        if (!function_exists('apcu_fetch') || !ini_get('apc.enabled') || ('cli' === PHP_SAPI && !ini_get('apc.enable_cli'))) {
+        if (!\function_exists('apcu_fetch') || !ini_get('apc.enabled') || ('cli' === PHP_SAPI && !ini_get('apc.enable_cli'))) {
             $this->markTestSkipped('APCu extension is required.');
         }
         if ('\\' === DIRECTORY_SEPARATOR) {
diff --git a/src/Symfony/Component/Cache/Tests/Simple/PdoCacheTest.php b/src/Symfony/Component/Cache/Tests/Simple/PdoCacheTest.php
index cf5730952d..665db09f67 100644
--- a/src/Symfony/Component/Cache/Tests/Simple/PdoCacheTest.php
+++ b/src/Symfony/Component/Cache/Tests/Simple/PdoCacheTest.php
@@ -25,7 +25,7 @@ class PdoCacheTest extends CacheTestCase
 
     public static function setupBeforeClass()
     {
-        if (!extension_loaded('pdo_sqlite')) {
+        if (!\extension_loaded('pdo_sqlite')) {
             self::markTestSkipped('Extension pdo_sqlite required.');
         }
 
diff --git a/src/Symfony/Component/Cache/Tests/Simple/PdoDbalCacheTest.php b/src/Symfony/Component/Cache/Tests/Simple/PdoDbalCacheTest.php
index 0c40c04a2c..158e2c8924 100644
--- a/src/Symfony/Component/Cache/Tests/Simple/PdoDbalCacheTest.php
+++ b/src/Symfony/Component/Cache/Tests/Simple/PdoDbalCacheTest.php
@@ -26,7 +26,7 @@ class PdoDbalCacheTest extends CacheTestCase
 
     public static function setupBeforeClass()
     {
-        if (!extension_loaded('pdo_sqlite')) {
+        if (!\extension_loaded('pdo_sqlite')) {
             self::markTestSkipped('Extension pdo_sqlite required.');
         }
 
diff --git a/src/Symfony/Component/Cache/Tests/Simple/PhpArrayCacheTest.php b/src/Symfony/Component/Cache/Tests/Simple/PhpArrayCacheTest.php
index 437a33ad3e..d6e1a807a6 100644
--- a/src/Symfony/Component/Cache/Tests/Simple/PhpArrayCacheTest.php
+++ b/src/Symfony/Component/Cache/Tests/Simple/PhpArrayCacheTest.php
@@ -134,7 +134,7 @@ class PhpArrayCacheWrapper extends PhpArrayCache
 
     public function set($key, $value, $ttl = null)
     {
-        call_user_func(\Closure::bind(function () use ($key, $value) {
+        \call_user_func(\Closure::bind(function () use ($key, $value) {
             $this->data[$key] = $value;
             $this->warmUp($this->data);
             list($this->keys, $this->values) = eval(substr(file_get_contents($this->file), 6));
@@ -145,10 +145,10 @@ class PhpArrayCacheWrapper extends PhpArrayCache
 
     public function setMultiple($values, $ttl = null)
     {
-        if (!is_array($values) && !$values instanceof \Traversable) {
+        if (!\is_array($values) && !$values instanceof \Traversable) {
             return parent::setMultiple($values, $ttl);
         }
-        call_user_func(\Closure::bind(function () use ($values) {
+        \call_user_func(\Closure::bind(function () use ($values) {
             foreach ($values as $key => $value) {
                 $this->data[$key] = $value;
             }
diff --git a/src/Symfony/Component/Cache/Tests/Traits/PdoPruneableTrait.php b/src/Symfony/Component/Cache/Tests/Traits/PdoPruneableTrait.php
index a9c459fb87..3b1e1128ba 100644
--- a/src/Symfony/Component/Cache/Tests/Traits/PdoPruneableTrait.php
+++ b/src/Symfony/Component/Cache/Tests/Traits/PdoPruneableTrait.php
@@ -29,6 +29,6 @@ trait PdoPruneableTrait
         $select->bindValue(':id', sprintf('%%%s', $name));
         $select->execute();
 
-        return 0 === count($select->fetchAll(\PDO::FETCH_COLUMN));
+        return 0 === \count($select->fetchAll(\PDO::FETCH_COLUMN));
     }
 }
diff --git a/src/Symfony/Component/Cache/Traits/ApcuTrait.php b/src/Symfony/Component/Cache/Traits/ApcuTrait.php
index 02ca023b08..8414074aca 100644
--- a/src/Symfony/Component/Cache/Traits/ApcuTrait.php
+++ b/src/Symfony/Component/Cache/Traits/ApcuTrait.php
@@ -23,7 +23,7 @@ trait ApcuTrait
 {
     public static function isSupported()
     {
-        return function_exists('apcu_fetch') && ini_get('apc.enabled');
+        return \function_exists('apcu_fetch') && ini_get('apc.enabled');
     }
 
     private function init($namespace, $defaultLifetime, $version)
@@ -110,7 +110,7 @@ trait ApcuTrait
 
             return array_keys($failures);
         } catch (\Throwable $e) {
-            if (1 === count($values)) {
+            if (1 === \count($values)) {
                 // Workaround https://github.com/krakjoe/apcu/issues/170
                 apcu_delete(key($values));
             }
diff --git a/src/Symfony/Component/Cache/Traits/ArrayTrait.php b/src/Symfony/Component/Cache/Traits/ArrayTrait.php
index 9cedb8d2cc..cfa73fa7b0 100644
--- a/src/Symfony/Component/Cache/Traits/ArrayTrait.php
+++ b/src/Symfony/Component/Cache/Traits/ArrayTrait.php
@@ -127,7 +127,7 @@ trait ArrayTrait
             try {
                 $serialized = serialize($value);
             } catch (\Exception $e) {
-                $type = is_object($value) ? get_class($value) : gettype($value);
+                $type = \is_object($value) ? \get_class($value) : \gettype($value);
                 CacheItem::log($this->logger, 'Failed to save key "{key}" ({type})', array('key' => $key, 'type' => $type, 'exception' => $e));
 
                 return;
diff --git a/src/Symfony/Component/Cache/Traits/FilesystemCommonTrait.php b/src/Symfony/Component/Cache/Traits/FilesystemCommonTrait.php
index 2f1764c425..03de037e6f 100644
--- a/src/Symfony/Component/Cache/Traits/FilesystemCommonTrait.php
+++ b/src/Symfony/Component/Cache/Traits/FilesystemCommonTrait.php
@@ -41,7 +41,7 @@ trait FilesystemCommonTrait
         }
         $directory .= DIRECTORY_SEPARATOR;
         // On Windows the whole path is limited to 258 chars
-        if ('\\' === DIRECTORY_SEPARATOR && strlen($directory) > 234) {
+        if ('\\' === DIRECTORY_SEPARATOR && \strlen($directory) > 234) {
             throw new InvalidArgumentException(sprintf('Cache directory too long (%s)', $directory));
         }
 
diff --git a/src/Symfony/Component/Cache/Traits/MemcachedTrait.php b/src/Symfony/Component/Cache/Traits/MemcachedTrait.php
index f312898355..1a9794454f 100644
--- a/src/Symfony/Component/Cache/Traits/MemcachedTrait.php
+++ b/src/Symfony/Component/Cache/Traits/MemcachedTrait.php
@@ -37,7 +37,7 @@ trait MemcachedTrait
 
     public static function isSupported()
     {
-        return extension_loaded('memcached') && version_compare(phpversion('memcached'), '2.2.0', '>=');
+        return \extension_loaded('memcached') && version_compare(phpversion('memcached'), '2.2.0', '>=');
     }
 
     private function init(\Memcached $client, $namespace, $defaultLifetime, ?MarshallerInterface $marshaller)
@@ -45,12 +45,12 @@ trait MemcachedTrait
         if (!static::isSupported()) {
             throw new CacheException('Memcached >= 2.2.0 is required');
         }
-        if ('Memcached' === get_class($client)) {
+        if ('Memcached' === \get_class($client)) {
             $opt = $client->getOption(\Memcached::OPT_SERIALIZER);
             if (\Memcached::SERIALIZER_PHP !== $opt && \Memcached::SERIALIZER_IGBINARY !== $opt) {
                 throw new CacheException('MemcachedAdapter: "serializer" option must be "php" or "igbinary".');
             }
-            $this->maxIdLength -= strlen($client->getOption(\Memcached::OPT_PREFIX_KEY));
+            $this->maxIdLength -= \strlen($client->getOption(\Memcached::OPT_PREFIX_KEY));
             $this->client = $client;
         } else {
             $this->lazyClient = $client;
@@ -79,10 +79,10 @@ trait MemcachedTrait
      */
     public static function createConnection($servers, array $options = array())
     {
-        if (is_string($servers)) {
+        if (\is_string($servers)) {
             $servers = array($servers);
-        } elseif (!is_array($servers)) {
-            throw new InvalidArgumentException(sprintf('MemcachedAdapter::createClient() expects array or string as first argument, %s given.', gettype($servers)));
+        } elseif (!\is_array($servers)) {
+            throw new InvalidArgumentException(sprintf('MemcachedAdapter::createClient() expects array or string as first argument, %s given.', \gettype($servers)));
         }
         if (!static::isSupported()) {
             throw new CacheException('Memcached >= 2.2.0 is required');
@@ -96,7 +96,7 @@ trait MemcachedTrait
 
             // parse any DSN in $servers
             foreach ($servers as $i => $dsn) {
-                if (is_array($dsn)) {
+                if (\is_array($dsn)) {
                     continue;
                 }
                 if (0 !== strpos($dsn, 'memcached://')) {
@@ -117,7 +117,7 @@ trait MemcachedTrait
                 }
                 if (isset($params['path']) && preg_match('#/(\d+)$#', $params['path'], $m)) {
                     $params['weight'] = $m[1];
-                    $params['path'] = substr($params['path'], 0, -strlen($m[0]));
+                    $params['path'] = substr($params['path'], 0, -\strlen($m[0]));
                 }
                 $params += array(
                     'host' => isset($params['host']) ? $params['host'] : $params['path'],
@@ -142,13 +142,13 @@ trait MemcachedTrait
                 $client->setOption(\Memcached::OPT_LIBKETAMA_COMPATIBLE, true);
             }
             foreach ($options as $name => $value) {
-                if (is_int($name)) {
+                if (\is_int($name)) {
                     continue;
                 }
                 if ('HASH' === $name || 'SERIALIZER' === $name || 'DISTRIBUTION' === $name) {
-                    $value = constant('Memcached::'.$name.'_'.strtoupper($value));
+                    $value = \constant('Memcached::'.$name.'_'.strtoupper($value));
                 }
-                $opt = constant('Memcached::OPT_'.$name);
+                $opt = \constant('Memcached::OPT_'.$name);
 
                 unset($options[$name]);
                 $options[$opt] = $value;
@@ -164,7 +164,7 @@ trait MemcachedTrait
 
                 $newServers = array();
                 foreach ($servers as $server) {
-                    if (1 < count($server)) {
+                    if (1 < \count($server)) {
                         $server = array_values($server);
                         unset($server[2]);
                         $server[1] = (int) $server[1];
diff --git a/src/Symfony/Component/Cache/Traits/PdoTrait.php b/src/Symfony/Component/Cache/Traits/PdoTrait.php
index 209858f5d5..2a59139719 100644
--- a/src/Symfony/Component/Cache/Traits/PdoTrait.php
+++ b/src/Symfony/Component/Cache/Traits/PdoTrait.php
@@ -54,10 +54,10 @@ trait PdoTrait
             $this->conn = $connOrDsn;
         } elseif ($connOrDsn instanceof Connection) {
             $this->conn = $connOrDsn;
-        } elseif (is_string($connOrDsn)) {
+        } elseif (\is_string($connOrDsn)) {
             $this->dsn = $connOrDsn;
         } else {
-            throw new InvalidArgumentException(sprintf('"%s" requires PDO or Doctrine\DBAL\Connection instance or DSN string as first argument, "%s" given.', __CLASS__, is_object($connOrDsn) ? get_class($connOrDsn) : gettype($connOrDsn)));
+            throw new InvalidArgumentException(sprintf('"%s" requires PDO or Doctrine\DBAL\Connection instance or DSN string as first argument, "%s" given.', __CLASS__, \is_object($connOrDsn) ? \get_class($connOrDsn) : \gettype($connOrDsn)));
         }
 
         $this->table = isset($options['db_table']) ? $options['db_table'] : $this->table;
@@ -177,7 +177,7 @@ trait PdoTrait
         $now = time();
         $expired = array();
 
-        $sql = str_pad('', (count($ids) << 1) - 1, '?,');
+        $sql = str_pad('', (\count($ids) << 1) - 1, '?,');
         $sql = "SELECT $this->idCol, CASE WHEN $this->lifetimeCol IS NULL OR $this->lifetimeCol + $this->timeCol > ? THEN $this->dataCol ELSE NULL END FROM $this->table WHERE $this->idCol IN ($sql)";
         $stmt = $this->getConnection()->prepare($sql);
         $stmt->bindValue($i = 1, $now, \PDO::PARAM_INT);
@@ -190,12 +190,12 @@ trait PdoTrait
             if (null === $row[1]) {
                 $expired[] = $row[0];
             } else {
-                yield $row[0] => $this->marshaller->unmarshall(is_resource($row[1]) ? stream_get_contents($row[1]) : $row[1]);
+                yield $row[0] => $this->marshaller->unmarshall(\is_resource($row[1]) ? stream_get_contents($row[1]) : $row[1]);
             }
         }
 
         if ($expired) {
-            $sql = str_pad('', (count($expired) << 1) - 1, '?,');
+            $sql = str_pad('', (\count($expired) << 1) - 1, '?,');
             $sql = "DELETE FROM $this->table WHERE $this->lifetimeCol + $this->timeCol <= ? AND $this->idCol IN ($sql)";
             $stmt = $this->getConnection()->prepare($sql);
             $stmt->bindValue($i = 1, $now, \PDO::PARAM_INT);
@@ -251,7 +251,7 @@ trait PdoTrait
      */
     protected function doDelete(array $ids)
     {
-        $sql = str_pad('', (count($ids) << 1) - 1, '?,');
+        $sql = str_pad('', (\count($ids) << 1) - 1, '?,');
         $sql = "DELETE FROM $this->table WHERE $this->idCol IN ($sql)";
         try {
             $stmt = $this->getConnection()->prepare($sql);
diff --git a/src/Symfony/Component/Cache/Traits/PhpArrayTrait.php b/src/Symfony/Component/Cache/Traits/PhpArrayTrait.php
index 249300684b..cb5eb31f36 100644
--- a/src/Symfony/Component/Cache/Traits/PhpArrayTrait.php
+++ b/src/Symfony/Component/Cache/Traits/PhpArrayTrait.php
@@ -45,7 +45,7 @@ trait PhpArrayTrait
                 throw new InvalidArgumentException(sprintf('Cache file is not writable: %s.', $this->file));
             }
         } else {
-            $directory = dirname($this->file);
+            $directory = \dirname($this->file);
 
             if (!is_dir($directory) && !@mkdir($directory, 0777, true)) {
                 throw new InvalidArgumentException(sprintf('Cache directory does not exist and cannot be created: %s.', $directory));
@@ -81,7 +81,7 @@ EOF;
                 } catch (\Exception $e) {
                 }
                 if (null !== $e || false === $serialized) {
-                    throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, \is_object($value) ? get_class($value) : 'array'), 0, $e);
+                    throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, \is_object($value) ? \get_class($value) : 'array'), 0, $e);
                 }
                 // Keep value serialized if it contains any internal references
                 $value = false !== strpos($serialized, ';R:') ? $serialized : PhpMarshaller::marshall($value, $objectsCount);
@@ -91,7 +91,7 @@ EOF;
                     ++$objectsCount;
                 }
             } elseif (!\is_scalar($value)) {
-                throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, gettype($value)));
+                throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, \gettype($value)));
             }
 
             $value = var_export($value, true);
diff --git a/src/Symfony/Component/Cache/Traits/PhpFilesTrait.php b/src/Symfony/Component/Cache/Traits/PhpFilesTrait.php
index bb3c334c28..ed5afb0471 100644
--- a/src/Symfony/Component/Cache/Traits/PhpFilesTrait.php
+++ b/src/Symfony/Component/Cache/Traits/PhpFilesTrait.php
@@ -175,7 +175,7 @@ trait PhpFilesTrait
                 } catch (\Exception $e) {
                 }
                 if (null !== $e || false === $serialized) {
-                    throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, \is_object($value) ? get_class($value) : 'array'), 0, $e);
+                    throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, \is_object($value) ? \get_class($value) : 'array'), 0, $e);
                 }
                 // Keep value serialized if it contains any internal references
                 $value = false !== strpos($serialized, ';R:') ? $serialized : PhpMarshaller::marshall($value, $objectsCount);
@@ -185,7 +185,7 @@ trait PhpFilesTrait
                     ++$objectsCount;
                 }
             } elseif (!\is_scalar($value)) {
-                throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, gettype($value)));
+                throw new InvalidArgumentException(sprintf('Cache key "%s" has non-serializable %s value.', $key, \gettype($value)));
             }
 
             $value = var_export($value, true);
diff --git a/src/Symfony/Component/Cache/Traits/RedisTrait.php b/src/Symfony/Component/Cache/Traits/RedisTrait.php
index 7a6f978937..d7935e8fb0 100644
--- a/src/Symfony/Component/Cache/Traits/RedisTrait.php
+++ b/src/Symfony/Component/Cache/Traits/RedisTrait.php
@@ -56,7 +56,7 @@ trait RedisTrait
         if ($redisClient instanceof \RedisCluster) {
             $this->enableVersioning();
         } elseif (!$redisClient instanceof \Redis && !$redisClient instanceof \RedisArray && !$redisClient instanceof \Predis\Client && !$redisClient instanceof RedisProxy) {
-            throw new InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, is_object($redisClient) ? get_class($redisClient) : gettype($redisClient)));
+            throw new InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, \is_object($redisClient) ? \get_class($redisClient) : \gettype($redisClient)));
         }
         $this->redis = $redisClient;
         $this->marshaller = $marshaller ?? new DefaultMarshaller();
@@ -99,7 +99,7 @@ trait RedisTrait
         }
         if (isset($params['path']) && preg_match('#/(\d+)$#', $params['path'], $m)) {
             $params['dbindex'] = $m[1];
-            $params['path'] = substr($params['path'], 0, -strlen($m[0]));
+            $params['path'] = substr($params['path'], 0, -\strlen($m[0]));
         }
         if (isset($params['host'])) {
             $scheme = 'tcp';
@@ -116,10 +116,10 @@ trait RedisTrait
             $params += $query;
         }
         $params += $options + self::$defaultConnectionOptions;
-        if (null === $params['class'] && !extension_loaded('redis') && !class_exists(\Predis\Client::class)) {
+        if (null === $params['class'] && !\extension_loaded('redis') && !class_exists(\Predis\Client::class)) {
             throw new CacheException(sprintf('Cannot find the "redis" extension, and "predis/predis" is not installed: %s', $dsn));
         }
-        $class = null === $params['class'] ? (extension_loaded('redis') ? \Redis::class : \Predis\Client::class) : $params['class'];
+        $class = null === $params['class'] ? (\extension_loaded('redis') ? \Redis::class : \Predis\Client::class) : $params['class'];
 
         if (is_a($class, \Redis::class, true)) {
             $connect = $params['persistent'] || $params['persistent_id'] ? 'pconnect' : 'connect';
@@ -315,7 +315,7 @@ trait RedisTrait
         if ($this->redis instanceof \Predis\Client && !$this->redis->getConnection() instanceof ClusterInterface) {
             $results = $this->redis->pipeline(function ($redis) use ($generator, &$ids) {
                 foreach ($generator() as $command => $args) {
-                    call_user_func_array(array($redis, $command), $args);
+                    \call_user_func_array(array($redis, $command), $args);
                     $ids[] = $args[0];
                 }
             });
@@ -326,7 +326,7 @@ trait RedisTrait
                     $connections[$h] = array($this->redis->_instance($h), -1);
                     $connections[$h][0]->multi(\Redis::PIPELINE);
                 }
-                call_user_func_array(array($connections[$h][0], $command), $args);
+                \call_user_func_array(array($connections[$h][0], $command), $args);
                 $results[] = array($h, ++$connections[$h][1]);
                 $ids[] = $args[0];
             }
@@ -342,13 +342,13 @@ trait RedisTrait
             // see https://github.com/nrk/predis/issues/267#issuecomment-123781423
             $results = array();
             foreach ($generator() as $command => $args) {
-                $results[] = call_user_func_array(array($this->redis, $command), $args);
+                $results[] = \call_user_func_array(array($this->redis, $command), $args);
                 $ids[] = $args[0];
             }
         } else {
             $this->redis->multi(\Redis::PIPELINE);
             foreach ($generator() as $command => $args) {
-                call_user_func_array(array($this->redis, $command), $args);
+                \call_user_func_array(array($this->redis, $command), $args);
                 $ids[] = $args[0];
             }
             $results = $this->redis->exec();
diff --git a/src/Symfony/Component/Config/ConfigCacheFactory.php b/src/Symfony/Component/Config/ConfigCacheFactory.php
index e43e1a190b..1e71ea0fbf 100644
--- a/src/Symfony/Component/Config/ConfigCacheFactory.php
+++ b/src/Symfony/Component/Config/ConfigCacheFactory.php
@@ -37,13 +37,13 @@ class ConfigCacheFactory implements ConfigCacheFactoryInterface
      */
     public function cache($file, $callback)
     {
-        if (!is_callable($callback)) {
-            throw new \InvalidArgumentException(sprintf('Invalid type for callback argument. Expected callable, but got "%s".', gettype($callback)));
+        if (!\is_callable($callback)) {
+            throw new \InvalidArgumentException(sprintf('Invalid type for callback argument. Expected callable, but got "%s".', \gettype($callback)));
         }
 
         $cache = new ConfigCache($file, $this->debug);
         if (!$cache->isFresh()) {
-            call_user_func($callback, $cache);
+            \call_user_func($callback, $cache);
         }
 
         return $cache;
diff --git a/src/Symfony/Component/Config/Definition/ArrayNode.php b/src/Symfony/Component/Config/Definition/ArrayNode.php
index ae4d3d9095..87007b2b36 100644
--- a/src/Symfony/Component/Config/Definition/ArrayNode.php
+++ b/src/Symfony/Component/Config/Definition/ArrayNode.php
@@ -52,7 +52,7 @@ class ArrayNode extends BaseNode implements PrototypeNodeInterface
      */
     protected function preNormalize($value)
     {
-        if (!$this->normalizeKeys || !is_array($value)) {
+        if (!$this->normalizeKeys || !\is_array($value)) {
             return $value;
         }
 
@@ -196,7 +196,7 @@ class ArrayNode extends BaseNode implements PrototypeNodeInterface
     public function addChild(NodeInterface $node)
     {
         $name = $node->getName();
-        if (!strlen($name)) {
+        if (!\strlen($name)) {
             throw new \InvalidArgumentException('Child nodes must be named.');
         }
         if (isset($this->children[$name])) {
@@ -263,11 +263,11 @@ class ArrayNode extends BaseNode implements PrototypeNodeInterface
      */
     protected function validateType($value)
     {
-        if (!is_array($value) && (!$this->allowFalse || false !== $value)) {
+        if (!\is_array($value) && (!$this->allowFalse || false !== $value)) {
             $ex = new InvalidTypeException(sprintf(
                 'Invalid type for path "%s". Expected array, but got %s',
                 $this->getPath(),
-                gettype($value)
+                \gettype($value)
             ));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
@@ -306,8 +306,8 @@ class ArrayNode extends BaseNode implements PrototypeNodeInterface
         }
 
         // if extra fields are present, throw exception
-        if (count($value) && !$this->ignoreExtraKeys) {
-            $msg = sprintf('Unrecognized option%s "%s" under "%s"', 1 === count($value) ? '' : 's', implode(', ', array_keys($value)), $this->getPath());
+        if (\count($value) && !$this->ignoreExtraKeys) {
+            $msg = sprintf('Unrecognized option%s "%s" under "%s"', 1 === \count($value) ? '' : 's', implode(', ', array_keys($value)), $this->getPath());
             $ex = new InvalidConfigurationException($msg);
             $ex->setPath($this->getPath());
 
diff --git a/src/Symfony/Component/Config/Definition/BaseNode.php b/src/Symfony/Component/Config/Definition/BaseNode.php
index 00aa212bdc..f9cf829e4e 100644
--- a/src/Symfony/Component/Config/Definition/BaseNode.php
+++ b/src/Symfony/Component/Config/Definition/BaseNode.php
@@ -510,7 +510,7 @@ abstract class BaseNode implements NodeInterface
     private function doValidateType($value): void
     {
         if (null !== $this->handlingPlaceholder && !$this->allowPlaceholders()) {
-            $e = new InvalidTypeException(sprintf('A dynamic value is not compatible with a "%s" node type at path "%s".', get_class($this), $this->getPath()));
+            $e = new InvalidTypeException(sprintf('A dynamic value is not compatible with a "%s" node type at path "%s".', \get_class($this), $this->getPath()));
             $e->setPath($this->getPath());
 
             throw $e;
@@ -529,8 +529,8 @@ abstract class BaseNode implements NodeInterface
             $e = new InvalidTypeException(sprintf(
                 'Invalid type for path "%s". Expected %s, but got %s.',
                 $this->getPath(),
-                1 === count($validTypes) ? '"'.reset($validTypes).'"' : 'one of "'.implode('", "', $validTypes).'"',
-                1 === count($knownTypes) ? '"'.reset($knownTypes).'"' : 'one of "'.implode('", "', $knownTypes).'"'
+                1 === \count($validTypes) ? '"'.reset($validTypes).'"' : 'one of "'.implode('", "', $validTypes).'"',
+                1 === \count($knownTypes) ? '"'.reset($knownTypes).'"' : 'one of "'.implode('", "', $knownTypes).'"'
             ));
             if ($hint = $this->getInfo()) {
                 $e->addHint($hint);
diff --git a/src/Symfony/Component/Config/Definition/BooleanNode.php b/src/Symfony/Component/Config/Definition/BooleanNode.php
index bf15fcb73c..6be06bbb6b 100644
--- a/src/Symfony/Component/Config/Definition/BooleanNode.php
+++ b/src/Symfony/Component/Config/Definition/BooleanNode.php
@@ -25,11 +25,11 @@ class BooleanNode extends ScalarNode
      */
     protected function validateType($value)
     {
-        if (!is_bool($value)) {
+        if (!\is_bool($value)) {
             $ex = new InvalidTypeException(sprintf(
                 'Invalid type for path "%s". Expected boolean, but got %s.',
                 $this->getPath(),
-                gettype($value)
+                \gettype($value)
             ));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
diff --git a/src/Symfony/Component/Config/Definition/Builder/ArrayNodeDefinition.php b/src/Symfony/Component/Config/Definition/Builder/ArrayNodeDefinition.php
index febcc67c7c..42fe087914 100644
--- a/src/Symfony/Component/Config/Definition/Builder/ArrayNodeDefinition.php
+++ b/src/Symfony/Component/Config/Definition/Builder/ArrayNodeDefinition.php
@@ -518,13 +518,13 @@ class ArrayNodeDefinition extends NodeDefinition implements ParentNodeDefinition
                 );
             }
 
-            if (null !== $this->key && (null === $this->addDefaultChildren || is_int($this->addDefaultChildren) && $this->addDefaultChildren > 0)) {
+            if (null !== $this->key && (null === $this->addDefaultChildren || \is_int($this->addDefaultChildren) && $this->addDefaultChildren > 0)) {
                 throw new InvalidDefinitionException(
                     sprintf('->addDefaultChildrenIfNoneSet() should set default children names as ->useAttributeAsKey() is used at path "%s"', $path)
                 );
             }
 
-            if (null === $this->key && (is_string($this->addDefaultChildren) || is_array($this->addDefaultChildren))) {
+            if (null === $this->key && (\is_string($this->addDefaultChildren) || \is_array($this->addDefaultChildren))) {
                 throw new InvalidDefinitionException(
                     sprintf('->addDefaultChildrenIfNoneSet() might not set default children names as ->useAttributeAsKey() is not used at path "%s"', $path)
                 );
diff --git a/src/Symfony/Component/Config/Definition/Builder/ExprBuilder.php b/src/Symfony/Component/Config/Definition/Builder/ExprBuilder.php
index 64c0f5578a..5c070bee7c 100644
--- a/src/Symfony/Component/Config/Definition/Builder/ExprBuilder.php
+++ b/src/Symfony/Component/Config/Definition/Builder/ExprBuilder.php
@@ -71,7 +71,7 @@ class ExprBuilder
      */
     public function ifString()
     {
-        $this->ifPart = function ($v) { return is_string($v); };
+        $this->ifPart = function ($v) { return \is_string($v); };
 
         return $this;
     }
@@ -107,7 +107,7 @@ class ExprBuilder
      */
     public function ifArray()
     {
-        $this->ifPart = function ($v) { return is_array($v); };
+        $this->ifPart = function ($v) { return \is_array($v); };
 
         return $this;
     }
@@ -119,7 +119,7 @@ class ExprBuilder
      */
     public function ifInArray(array $array)
     {
-        $this->ifPart = function ($v) use ($array) { return in_array($v, $array, true); };
+        $this->ifPart = function ($v) use ($array) { return \in_array($v, $array, true); };
 
         return $this;
     }
@@ -131,7 +131,7 @@ class ExprBuilder
      */
     public function ifNotInArray(array $array)
     {
-        $this->ifPart = function ($v) use ($array) { return !in_array($v, $array, true); };
+        $this->ifPart = function ($v) use ($array) { return !\in_array($v, $array, true); };
 
         return $this;
     }
@@ -143,7 +143,7 @@ class ExprBuilder
      */
     public function castToArray()
     {
-        $this->ifPart = function ($v) { return !is_array($v); };
+        $this->ifPart = function ($v) { return !\is_array($v); };
         $this->thenPart = function ($v) { return array($v); };
 
         return $this;
diff --git a/src/Symfony/Component/Config/Definition/Dumper/XmlReferenceDumper.php b/src/Symfony/Component/Config/Definition/Dumper/XmlReferenceDumper.php
index b87acc93d4..130b927973 100644
--- a/src/Symfony/Component/Config/Definition/Dumper/XmlReferenceDumper.php
+++ b/src/Symfony/Component/Config/Definition/Dumper/XmlReferenceDumper.php
@@ -52,7 +52,7 @@ class XmlReferenceDumper
                 return $rootName === $mapping[1];
             });
 
-            if (count($remapping)) {
+            if (\count($remapping)) {
                 list($singular) = current($remapping);
                 $rootName = $singular;
             }
@@ -99,7 +99,7 @@ class XmlReferenceDumper
                     if ($prototype->hasDefaultValue()) {
                         $prototypeValue = $prototype->getDefaultValue();
                     } else {
-                        switch (get_class($prototype)) {
+                        switch (\get_class($prototype)) {
                             case 'Symfony\Component\Config\Definition\ScalarNode':
                                 $prototypeValue = 'scalar value';
                                 break;
@@ -155,7 +155,7 @@ class XmlReferenceDumper
                         $comments[] = 'One of '.implode('; ', array_map('json_encode', $child->getValues()));
                     }
 
-                    if (count($comments)) {
+                    if (\count($comments)) {
                         $rootAttributeComments[$name] = implode(";\n", $comments);
                     }
 
@@ -176,18 +176,18 @@ class XmlReferenceDumper
         // render comments
 
         // root node comment
-        if (count($rootComments)) {
+        if (\count($rootComments)) {
             foreach ($rootComments as $comment) {
                 $this->writeLine('<!-- '.$comment.' -->', $depth);
             }
         }
 
         // attribute comments
-        if (count($rootAttributeComments)) {
+        if (\count($rootAttributeComments)) {
             foreach ($rootAttributeComments as $attrName => $comment) {
-                $commentDepth = $depth + 4 + strlen($attrName) + 2;
+                $commentDepth = $depth + 4 + \strlen($attrName) + 2;
                 $commentLines = explode("\n", $comment);
-                $multiline = (count($commentLines) > 1);
+                $multiline = (\count($commentLines) > 1);
                 $comment = implode(PHP_EOL.str_repeat(' ', $commentDepth), $commentLines);
 
                 if ($multiline) {
@@ -202,9 +202,9 @@ class XmlReferenceDumper
 
         // render start tag + attributes
         $rootIsVariablePrototype = isset($prototypeValue);
-        $rootIsEmptyTag = (0 === count($rootChildren) && !$rootIsVariablePrototype);
+        $rootIsEmptyTag = (0 === \count($rootChildren) && !$rootIsVariablePrototype);
         $rootOpenTag = '<'.$rootName;
-        if (1 >= ($attributesCount = count($rootAttributes))) {
+        if (1 >= ($attributesCount = \count($rootAttributes))) {
             if (1 === $attributesCount) {
                 $rootOpenTag .= sprintf(' %s="%s"', current(array_keys($rootAttributes)), $this->writeValue(current($rootAttributes)));
             }
@@ -256,7 +256,7 @@ class XmlReferenceDumper
      */
     private function writeLine(string $text, int $indent = 0)
     {
-        $indent = strlen($text) + $indent;
+        $indent = \strlen($text) + $indent;
         $format = '%'.$indent.'s';
 
         $this->reference .= sprintf($format, $text).PHP_EOL;
@@ -273,7 +273,7 @@ class XmlReferenceDumper
             return '';
         }
 
-        if (is_string($value) || is_numeric($value)) {
+        if (\is_string($value) || is_numeric($value)) {
             return $value;
         }
 
@@ -293,7 +293,7 @@ class XmlReferenceDumper
             return '';
         }
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             return implode(',', $value);
         }
     }
diff --git a/src/Symfony/Component/Config/Definition/Dumper/YamlReferenceDumper.php b/src/Symfony/Component/Config/Definition/Dumper/YamlReferenceDumper.php
index 960d136231..4a00d5d200 100644
--- a/src/Symfony/Component/Config/Definition/Dumper/YamlReferenceDumper.php
+++ b/src/Symfony/Component/Config/Definition/Dumper/YamlReferenceDumper.php
@@ -86,9 +86,9 @@ class YamlReferenceDumper
             }
 
             if (!$children) {
-                if ($node->hasDefaultValue() && count($defaultArray = $node->getDefaultValue())) {
+                if ($node->hasDefaultValue() && \count($defaultArray = $node->getDefaultValue())) {
                     $default = '';
-                } elseif (!is_array($example)) {
+                } elseif (!\is_array($example)) {
                     $default = '[]';
                 }
             }
@@ -101,10 +101,10 @@ class YamlReferenceDumper
             if ($node->hasDefaultValue()) {
                 $default = $node->getDefaultValue();
 
-                if (is_array($default)) {
-                    if (count($defaultArray = $node->getDefaultValue())) {
+                if (\is_array($default)) {
+                    if (\count($defaultArray = $node->getDefaultValue())) {
                         $default = '';
-                    } elseif (!is_array($example)) {
+                    } elseif (!\is_array($example)) {
                         $default = '[]';
                     }
                 } else {
@@ -124,12 +124,12 @@ class YamlReferenceDumper
         }
 
         // example
-        if ($example && !is_array($example)) {
+        if ($example && !\is_array($example)) {
             $comments[] = 'Example: '.$example;
         }
 
         $default = '' != (string) $default ? ' '.$default : '';
-        $comments = count($comments) ? '# '.implode(', ', $comments) : '';
+        $comments = \count($comments) ? '# '.implode(', ', $comments) : '';
 
         $key = $prototypedArray ? '-' : $node->getName().':';
         $text = rtrim(sprintf('%-21s%s %s', $key, $default, $comments), ' ');
@@ -147,17 +147,17 @@ class YamlReferenceDumper
         if ($defaultArray) {
             $this->writeLine('');
 
-            $message = count($defaultArray) > 1 ? 'Defaults' : 'Default';
+            $message = \count($defaultArray) > 1 ? 'Defaults' : 'Default';
 
             $this->writeLine('# '.$message.':', $depth * 4 + 4);
 
             $this->writeArray($defaultArray, $depth + 1);
         }
 
-        if (is_array($example)) {
+        if (\is_array($example)) {
             $this->writeLine('');
 
-            $message = count($example) > 1 ? 'Examples' : 'Example';
+            $message = \count($example) > 1 ? 'Examples' : 'Example';
 
             $this->writeLine('# '.$message.':', $depth * 4 + 4);
 
@@ -176,7 +176,7 @@ class YamlReferenceDumper
      */
     private function writeLine(string $text, int $indent = 0)
     {
-        $indent = strlen($text) + $indent;
+        $indent = \strlen($text) + $indent;
         $format = '%'.$indent.'s';
 
         $this->reference .= sprintf($format, $text)."\n";
@@ -187,7 +187,7 @@ class YamlReferenceDumper
         $isIndexed = array_values($array) === $array;
 
         foreach ($array as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $val = '';
             } else {
                 $val = $value;
@@ -199,7 +199,7 @@ class YamlReferenceDumper
                 $this->writeLine(sprintf('%-20s %s', $key.':', $val), $depth * 4);
             }
 
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $this->writeArray($value, $depth + 1);
             }
         }
diff --git a/src/Symfony/Component/Config/Definition/EnumNode.php b/src/Symfony/Component/Config/Definition/EnumNode.php
index cdc4366d54..a9bbb28afc 100644
--- a/src/Symfony/Component/Config/Definition/EnumNode.php
+++ b/src/Symfony/Component/Config/Definition/EnumNode.php
@@ -42,7 +42,7 @@ class EnumNode extends ScalarNode
     {
         $value = parent::finalizeValue($value);
 
-        if (!in_array($value, $this->values, true)) {
+        if (!\in_array($value, $this->values, true)) {
             $ex = new InvalidConfigurationException(sprintf(
                 'The value %s is not allowed for path "%s". Permissible values: %s',
                 json_encode($value),
diff --git a/src/Symfony/Component/Config/Definition/FloatNode.php b/src/Symfony/Component/Config/Definition/FloatNode.php
index 8f9f614bcf..173b76df38 100644
--- a/src/Symfony/Component/Config/Definition/FloatNode.php
+++ b/src/Symfony/Component/Config/Definition/FloatNode.php
@@ -26,12 +26,12 @@ class FloatNode extends NumericNode
     protected function validateType($value)
     {
         // Integers are also accepted, we just cast them
-        if (is_int($value)) {
+        if (\is_int($value)) {
             $value = (float) $value;
         }
 
-        if (!is_float($value)) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected float, but got %s.', $this->getPath(), gettype($value)));
+        if (!\is_float($value)) {
+            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected float, but got %s.', $this->getPath(), \gettype($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
diff --git a/src/Symfony/Component/Config/Definition/IntegerNode.php b/src/Symfony/Component/Config/Definition/IntegerNode.php
index f3e05fc35c..4523584986 100644
--- a/src/Symfony/Component/Config/Definition/IntegerNode.php
+++ b/src/Symfony/Component/Config/Definition/IntegerNode.php
@@ -25,8 +25,8 @@ class IntegerNode extends NumericNode
      */
     protected function validateType($value)
     {
-        if (!is_int($value)) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected int, but got %s.', $this->getPath(), gettype($value)));
+        if (!\is_int($value)) {
+            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected int, but got %s.', $this->getPath(), \gettype($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
diff --git a/src/Symfony/Component/Config/Definition/Processor.php b/src/Symfony/Component/Config/Definition/Processor.php
index c12c7218ad..4f4c66cadd 100644
--- a/src/Symfony/Component/Config/Definition/Processor.php
+++ b/src/Symfony/Component/Config/Definition/Processor.php
@@ -86,7 +86,7 @@ class Processor
         }
 
         if (isset($config[$key])) {
-            if (is_string($config[$key]) || !is_int(key($config[$key]))) {
+            if (\is_string($config[$key]) || !\is_int(key($config[$key]))) {
                 // only one
                 return  array($config[$key]);
             }
diff --git a/src/Symfony/Component/Config/Definition/PrototypedArrayNode.php b/src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
index d183a60525..ab03b04620 100644
--- a/src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
+++ b/src/Symfony/Component/Config/Definition/PrototypedArrayNode.php
@@ -94,7 +94,7 @@ class PrototypedArrayNode extends ArrayNode
      */
     public function setDefaultValue($value)
     {
-        if (!is_array($value)) {
+        if (!\is_array($value)) {
             throw new \InvalidArgumentException($this->getPath().': the default value of an array node has to be an array.');
         }
 
@@ -119,7 +119,7 @@ class PrototypedArrayNode extends ArrayNode
         if (null === $children) {
             $this->defaultChildren = array('defaults');
         } else {
-            $this->defaultChildren = is_int($children) && $children > 0 ? range(1, $children) : (array) $children;
+            $this->defaultChildren = \is_int($children) && $children > 0 ? range(1, $children) : (array) $children;
         }
     }
 
@@ -198,7 +198,7 @@ class PrototypedArrayNode extends ArrayNode
             }
         }
 
-        if (count($value) < $this->minNumberOfElements) {
+        if (\count($value) < $this->minNumberOfElements) {
             $msg = sprintf('The path "%s" should have at least %d element(s) defined.', $this->getPath(), $this->minNumberOfElements);
             $ex = new InvalidConfigurationException($msg);
             $ex->setPath($this->getPath());
@@ -227,11 +227,11 @@ class PrototypedArrayNode extends ArrayNode
 
         $value = $this->remapXml($value);
 
-        $isAssoc = array_keys($value) !== range(0, count($value) - 1);
+        $isAssoc = array_keys($value) !== range(0, \count($value) - 1);
         $normalized = array();
         foreach ($value as $k => $v) {
-            if (null !== $this->keyAttribute && is_array($v)) {
-                if (!isset($v[$this->keyAttribute]) && is_int($k) && !$isAssoc) {
+            if (null !== $this->keyAttribute && \is_array($v)) {
+                if (!isset($v[$this->keyAttribute]) && \is_int($k) && !$isAssoc) {
                     $msg = sprintf('The attribute "%s" must be set for path "%s".', $this->keyAttribute, $this->getPath());
                     $ex = new InvalidConfigurationException($msg);
                     $ex->setPath($this->getPath());
@@ -252,9 +252,9 @@ class PrototypedArrayNode extends ArrayNode
                             $valuePrototype = current($this->valuePrototypes) ?: clone $children['value'];
                             $valuePrototype->parent = $this;
                             $originalClosures = $this->prototype->normalizationClosures;
-                            if (is_array($originalClosures)) {
+                            if (\is_array($originalClosures)) {
                                 $valuePrototypeClosures = $valuePrototype->normalizationClosures;
-                                $valuePrototype->normalizationClosures = is_array($valuePrototypeClosures) ? array_merge($originalClosures, $valuePrototypeClosures) : $originalClosures;
+                                $valuePrototype->normalizationClosures = \is_array($valuePrototypeClosures) ? array_merge($originalClosures, $valuePrototypeClosures) : $originalClosures;
                             }
                             $this->valuePrototypes[$k] = $valuePrototype;
                         }
diff --git a/src/Symfony/Component/Config/Definition/ScalarNode.php b/src/Symfony/Component/Config/Definition/ScalarNode.php
index 5d4fe17373..97fa1ed22a 100644
--- a/src/Symfony/Component/Config/Definition/ScalarNode.php
+++ b/src/Symfony/Component/Config/Definition/ScalarNode.php
@@ -36,7 +36,7 @@ class ScalarNode extends VariableNode
             $ex = new InvalidTypeException(sprintf(
                 'Invalid type for path "%s". Expected scalar, but got %s.',
                 $this->getPath(),
-                gettype($value)
+                \gettype($value)
             ));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
diff --git a/src/Symfony/Component/Config/Exception/FileLoaderLoadException.php b/src/Symfony/Component/Config/Exception/FileLoaderLoadException.php
index 62e56622f3..1db59459e2 100644
--- a/src/Symfony/Component/Config/Exception/FileLoaderLoadException.php
+++ b/src/Symfony/Component/Config/Exception/FileLoaderLoadException.php
@@ -75,11 +75,11 @@ class FileLoaderLoadException extends \Exception
 
     protected function varToString($var)
     {
-        if (is_object($var)) {
-            return sprintf('Object(%s)', get_class($var));
+        if (\is_object($var)) {
+            return sprintf('Object(%s)', \get_class($var));
         }
 
-        if (is_array($var)) {
+        if (\is_array($var)) {
             $a = array();
             foreach ($var as $k => $v) {
                 $a[] = sprintf('%s => %s', $k, $this->varToString($v));
@@ -88,7 +88,7 @@ class FileLoaderLoadException extends \Exception
             return sprintf('Array(%s)', implode(', ', $a));
         }
 
-        if (is_resource($var)) {
+        if (\is_resource($var)) {
             return sprintf('Resource(%s)', get_resource_type($var));
         }
 
diff --git a/src/Symfony/Component/Config/FileLocator.php b/src/Symfony/Component/Config/FileLocator.php
index a3e8fd1104..099f075892 100644
--- a/src/Symfony/Component/Config/FileLocator.php
+++ b/src/Symfony/Component/Config/FileLocator.php
@@ -84,7 +84,7 @@ class FileLocator implements FileLocatorInterface
     private function isAbsolutePath($file)
     {
         if ('/' === $file[0] || '\\' === $file[0]
-            || (strlen($file) > 3 && ctype_alpha($file[0])
+            || (\strlen($file) > 3 && ctype_alpha($file[0])
                 && ':' === $file[1]
                 && ('\\' === $file[2] || '/' === $file[2])
             )
diff --git a/src/Symfony/Component/Config/Loader/FileLoader.php b/src/Symfony/Component/Config/Loader/FileLoader.php
index c06171992a..27fbcd3415 100644
--- a/src/Symfony/Component/Config/Loader/FileLoader.php
+++ b/src/Symfony/Component/Config/Loader/FileLoader.php
@@ -72,7 +72,7 @@ abstract class FileLoader extends Loader
      */
     public function import($resource, $type = null, $ignoreErrors = false, $sourceResource = null)
     {
-        if (is_string($resource) && strlen($resource) !== $i = strcspn($resource, '*?{[')) {
+        if (\is_string($resource) && \strlen($resource) !== $i = strcspn($resource, '*?{[')) {
             $ret = array();
             $isSubpath = 0 !== $i && false !== strpos(substr($resource, 0, $i), '/');
             foreach ($this->glob($resource, false, $_, $ignoreErrors || !$isSubpath) as $path => $info) {
@@ -95,15 +95,15 @@ abstract class FileLoader extends Loader
      */
     protected function glob(string $pattern, bool $recursive, &$resource = null, bool $ignoreErrors = false)
     {
-        if (strlen($pattern) === $i = strcspn($pattern, '*?{[')) {
+        if (\strlen($pattern) === $i = strcspn($pattern, '*?{[')) {
             $prefix = $pattern;
             $pattern = '';
         } elseif (0 === $i || false === strpos(substr($pattern, 0, $i), '/')) {
             $prefix = '.';
             $pattern = '/'.$pattern;
         } else {
-            $prefix = dirname(substr($pattern, 0, 1 + $i));
-            $pattern = substr($pattern, strlen($prefix));
+            $prefix = \dirname(substr($pattern, 0, 1 + $i));
+            $pattern = substr($pattern, \strlen($prefix));
         }
 
         try {
@@ -136,8 +136,8 @@ abstract class FileLoader extends Loader
                 $resource = $loader->getLocator()->locate($resource, $this->currentDir, false);
             }
 
-            $resources = is_array($resource) ? $resource : array($resource);
-            for ($i = 0; $i < $resourcesCount = count($resources); ++$i) {
+            $resources = \is_array($resource) ? $resource : array($resource);
+            for ($i = 0; $i < $resourcesCount = \count($resources); ++$i) {
                 if (isset(self::$loading[$resources[$i]])) {
                     if ($i == $resourcesCount - 1) {
                         throw new FileLoaderImportCircularReferenceException(array_keys(self::$loading));
diff --git a/src/Symfony/Component/Config/Resource/ClassExistenceResource.php b/src/Symfony/Component/Config/Resource/ClassExistenceResource.php
index a4dd74b1f9..800e14c7ff 100644
--- a/src/Symfony/Component/Config/Resource/ClassExistenceResource.php
+++ b/src/Symfony/Component/Config/Resource/ClassExistenceResource.php
@@ -152,7 +152,7 @@ class ClassExistenceResource implements SelfCheckingResourceInterface, \Serializ
             $props = array(
                 'file' => $trace[$i]['file'],
                 'line' => $trace[$i]['line'],
-                'trace' => array_slice($trace, 1 + $i),
+                'trace' => \array_slice($trace, 1 + $i),
             );
 
             foreach ($props as $p => $v) {
diff --git a/src/Symfony/Component/Config/Resource/ComposerResource.php b/src/Symfony/Component/Config/Resource/ComposerResource.php
index 64288ea1db..9c170c0775 100644
--- a/src/Symfony/Component/Config/Resource/ComposerResource.php
+++ b/src/Symfony/Component/Config/Resource/ComposerResource.php
@@ -68,7 +68,7 @@ class ComposerResource implements SelfCheckingResourceInterface, \Serializable
         foreach (get_declared_classes() as $class) {
             if ('C' === $class[0] && 0 === strpos($class, 'ComposerAutoloaderInit')) {
                 $r = new \ReflectionClass($class);
-                $v = dirname(dirname($r->getFileName()));
+                $v = \dirname(\dirname($r->getFileName()));
                 if (file_exists($v.'/composer/installed.json')) {
                     self::$runtimeVendors[$v] = @filemtime($v.'/composer/installed.json');
                 }
diff --git a/src/Symfony/Component/Config/Resource/GlobResource.php b/src/Symfony/Component/Config/Resource/GlobResource.php
index fb5fc4f693..a04cbf7be8 100644
--- a/src/Symfony/Component/Config/Resource/GlobResource.php
+++ b/src/Symfony/Component/Config/Resource/GlobResource.php
@@ -93,8 +93,8 @@ class GlobResource implements \IteratorAggregate, SelfCheckingResourceInterface,
             return;
         }
 
-        if (0 !== strpos($this->prefix, 'phar://') && false === strpos($this->pattern, '/**/') && (defined('GLOB_BRACE') || false === strpos($this->pattern, '{'))) {
-            foreach (glob($this->prefix.$this->pattern, defined('GLOB_BRACE') ? GLOB_BRACE : 0) as $path) {
+        if (0 !== strpos($this->prefix, 'phar://') && false === strpos($this->pattern, '/**/') && (\defined('GLOB_BRACE') || false === strpos($this->pattern, '{'))) {
+            foreach (glob($this->prefix.$this->pattern, \defined('GLOB_BRACE') ? GLOB_BRACE : 0) as $path) {
                 if ($this->recursive && is_dir($path)) {
                     $files = iterator_to_array(new \RecursiveIteratorIterator(
                         new \RecursiveCallbackFilterIterator(
@@ -130,7 +130,7 @@ class GlobResource implements \IteratorAggregate, SelfCheckingResourceInterface,
             $regex = substr_replace($regex, '(/|$)', -2, 1);
         }
 
-        $prefixLen = strlen($this->prefix);
+        $prefixLen = \strlen($this->prefix);
         foreach ($finder->followLinks()->sortByName()->in($this->prefix) as $path => $info) {
             if (preg_match($regex, substr('\\' === \DIRECTORY_SEPARATOR ? str_replace('\\', '/', $path) : $path, $prefixLen)) && $info->isFile()) {
                 yield $path => $info;
diff --git a/src/Symfony/Component/Config/Resource/ReflectionClassResource.php b/src/Symfony/Component/Config/Resource/ReflectionClassResource.php
index bf8e5625ac..93518d7fc5 100644
--- a/src/Symfony/Component/Config/Resource/ReflectionClassResource.php
+++ b/src/Symfony/Component/Config/Resource/ReflectionClassResource.php
@@ -81,7 +81,7 @@ class ReflectionClassResource implements SelfCheckingResourceInterface, \Seriali
             $file = $class->getFileName();
             if (false !== $file && file_exists($file)) {
                 foreach ($this->excludedVendors as $vendor) {
-                    if (0 === strpos($file, $vendor) && false !== strpbrk(substr($file, strlen($vendor), 1), '/'.DIRECTORY_SEPARATOR)) {
+                    if (0 === strpos($file, $vendor) && false !== strpbrk(substr($file, \strlen($vendor), 1), '/'.DIRECTORY_SEPARATOR)) {
                         $file = false;
                         break;
                     }
diff --git a/src/Symfony/Component/Config/ResourceCheckerConfigCache.php b/src/Symfony/Component/Config/ResourceCheckerConfigCache.php
index 6f64c4abcd..0b278fe9de 100644
--- a/src/Symfony/Component/Config/ResourceCheckerConfigCache.php
+++ b/src/Symfony/Component/Config/ResourceCheckerConfigCache.php
@@ -72,7 +72,7 @@ class ResourceCheckerConfigCache implements ConfigCacheInterface
             $this->resourceCheckers = iterator_to_array($this->resourceCheckers);
         }
 
-        if (!count($this->resourceCheckers)) {
+        if (!\count($this->resourceCheckers)) {
             return true; // shortcut - if we don't have any checkers we don't need to bother with the meta file at all
         }
 
diff --git a/src/Symfony/Component/Config/ResourceCheckerConfigCacheFactory.php b/src/Symfony/Component/Config/ResourceCheckerConfigCacheFactory.php
index 845eabdee8..4f45a9153a 100644
--- a/src/Symfony/Component/Config/ResourceCheckerConfigCacheFactory.php
+++ b/src/Symfony/Component/Config/ResourceCheckerConfigCacheFactory.php
@@ -34,13 +34,13 @@ class ResourceCheckerConfigCacheFactory implements ConfigCacheFactoryInterface
      */
     public function cache($file, $callback)
     {
-        if (!is_callable($callback)) {
-            throw new \InvalidArgumentException(sprintf('Invalid type for callback argument. Expected callable, but got "%s".', gettype($callback)));
+        if (!\is_callable($callback)) {
+            throw new \InvalidArgumentException(sprintf('Invalid type for callback argument. Expected callable, but got "%s".', \gettype($callback)));
         }
 
         $cache = new ResourceCheckerConfigCache($file, $this->resourceCheckers);
         if (!$cache->isFresh()) {
-            call_user_func($callback, $cache);
+            \call_user_func($callback, $cache);
         }
 
         return $cache;
diff --git a/src/Symfony/Component/Config/Tests/Definition/ArrayNodeTest.php b/src/Symfony/Component/Config/Tests/Definition/ArrayNodeTest.php
index 58d2939300..089cb56638 100644
--- a/src/Symfony/Component/Config/Tests/Definition/ArrayNodeTest.php
+++ b/src/Symfony/Component/Config/Tests/Definition/ArrayNodeTest.php
@@ -56,10 +56,10 @@ class ArrayNodeTest extends TestCase
     {
         if ($expected instanceof \Exception) {
             if (method_exists($this, 'expectException')) {
-                $this->expectException(get_class($expected));
+                $this->expectException(\get_class($expected));
                 $this->expectExceptionMessage($expected->getMessage());
             } else {
-                $this->setExpectedException(get_class($expected), $expected->getMessage());
+                $this->setExpectedException(\get_class($expected), $expected->getMessage());
             }
         }
         $node = new ArrayNode('root');
diff --git a/src/Symfony/Component/Config/Tests/Definition/Builder/ArrayNodeDefinitionTest.php b/src/Symfony/Component/Config/Tests/Definition/Builder/ArrayNodeDefinitionTest.php
index 2bd55575d0..8e581089f0 100644
--- a/src/Symfony/Component/Config/Tests/Definition/Builder/ArrayNodeDefinitionTest.php
+++ b/src/Symfony/Component/Config/Tests/Definition/Builder/ArrayNodeDefinitionTest.php
@@ -43,7 +43,7 @@ class ArrayNodeDefinitionTest extends TestCase
     {
         $node = new ArrayNodeDefinition('root');
 
-        call_user_func_array(array($node, $method), $args);
+        \call_user_func_array(array($node, $method), $args);
 
         $node->getNode();
     }
diff --git a/src/Symfony/Component/Config/Tests/Definition/Builder/NodeBuilderTest.php b/src/Symfony/Component/Config/Tests/Definition/Builder/NodeBuilderTest.php
index 8877565678..cd77dd702b 100644
--- a/src/Symfony/Component/Config/Tests/Definition/Builder/NodeBuilderTest.php
+++ b/src/Symfony/Component/Config/Tests/Definition/Builder/NodeBuilderTest.php
@@ -68,14 +68,14 @@ class NodeBuilderTest extends TestCase
         $node1 = $builder->node('', 'VaRiAbLe');
         $node2 = $builder->node('', 'variable');
 
-        $this->assertInstanceOf(get_class($node1), $node2);
+        $this->assertInstanceOf(\get_class($node1), $node2);
 
         $builder->setNodeClass('CuStOm', __NAMESPACE__.'\\SomeNodeDefinition');
 
         $node1 = $builder->node('', 'CUSTOM');
         $node2 = $builder->node('', 'custom');
 
-        $this->assertInstanceOf(get_class($node1), $node2);
+        $this->assertInstanceOf(\get_class($node1), $node2);
     }
 
     public function testNumericNodeCreation()
diff --git a/src/Symfony/Component/Config/Tests/Loader/LoaderTest.php b/src/Symfony/Component/Config/Tests/Loader/LoaderTest.php
index fefb1d728f..30167e3836 100644
--- a/src/Symfony/Component/Config/Tests/Loader/LoaderTest.php
+++ b/src/Symfony/Component/Config/Tests/Loader/LoaderTest.php
@@ -109,7 +109,7 @@ class ProjectLoader1 extends Loader
 
     public function supports($resource, $type = null)
     {
-        return is_string($resource) && 'foo' === pathinfo($resource, PATHINFO_EXTENSION);
+        return \is_string($resource) && 'foo' === pathinfo($resource, PATHINFO_EXTENSION);
     }
 
     public function getType()
diff --git a/src/Symfony/Component/Config/Tests/Resource/GlobResourceTest.php b/src/Symfony/Component/Config/Tests/Resource/GlobResourceTest.php
index bf7291fdd6..6fe078f977 100644
--- a/src/Symfony/Component/Config/Tests/Resource/GlobResourceTest.php
+++ b/src/Symfony/Component/Config/Tests/Resource/GlobResourceTest.php
@@ -18,7 +18,7 @@ class GlobResourceTest extends TestCase
 {
     protected function tearDown()
     {
-        $dir = dirname(__DIR__).'/Fixtures';
+        $dir = \dirname(__DIR__).'/Fixtures';
         @rmdir($dir.'/TmpGlob');
         @unlink($dir.'/TmpGlob');
         @unlink($dir.'/Resource/TmpGlob');
@@ -27,7 +27,7 @@ class GlobResourceTest extends TestCase
 
     public function testIterator()
     {
-        $dir = dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures';
+        $dir = \dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures';
         $resource = new GlobResource($dir, '/Resource', true);
 
         $paths = iterator_to_array($resource);
@@ -49,7 +49,7 @@ class GlobResourceTest extends TestCase
 
     public function testIsFreshNonRecursiveDetectsNewFile()
     {
-        $dir = dirname(__DIR__).'/Fixtures';
+        $dir = \dirname(__DIR__).'/Fixtures';
         $resource = new GlobResource($dir, '/*', false);
 
         $this->assertTrue($resource->isFresh(0));
@@ -69,7 +69,7 @@ class GlobResourceTest extends TestCase
 
     public function testIsFreshNonRecursiveDetectsRemovedFile()
     {
-        $dir = dirname(__DIR__).'/Fixtures';
+        $dir = \dirname(__DIR__).'/Fixtures';
         $resource = new GlobResource($dir, '/*', false);
 
         touch($dir.'/TmpGlob');
@@ -85,7 +85,7 @@ class GlobResourceTest extends TestCase
 
     public function testIsFreshRecursiveDetectsRemovedFile()
     {
-        $dir = dirname(__DIR__).'/Fixtures';
+        $dir = \dirname(__DIR__).'/Fixtures';
         $resource = new GlobResource($dir, '/*', true);
 
         touch($dir.'/Resource/TmpGlob');
@@ -103,7 +103,7 @@ class GlobResourceTest extends TestCase
 
     public function testIsFreshRecursiveDetectsNewFile()
     {
-        $dir = dirname(__DIR__).'/Fixtures';
+        $dir = \dirname(__DIR__).'/Fixtures';
         $resource = new GlobResource($dir, '/*', true);
 
         $this->assertTrue($resource->isFresh(0));
diff --git a/src/Symfony/Component/Config/Util/XmlUtils.php b/src/Symfony/Component/Config/Util/XmlUtils.php
index e1c4a4ad3f..d761e4e80f 100644
--- a/src/Symfony/Component/Config/Util/XmlUtils.php
+++ b/src/Symfony/Component/Config/Util/XmlUtils.php
@@ -46,7 +46,7 @@ class XmlUtils
      */
     public static function parse($content, $schemaOrCallable = null)
     {
-        if (!extension_loaded('dom')) {
+        if (!\extension_loaded('dom')) {
             throw new \RuntimeException('Extension DOM is required.');
         }
 
@@ -56,7 +56,7 @@ class XmlUtils
 
         $dom = new \DOMDocument();
         $dom->validateOnParse = true;
-        if (!$dom->loadXML($content, LIBXML_NONET | (defined('LIBXML_COMPACT') ? LIBXML_COMPACT : 0))) {
+        if (!$dom->loadXML($content, LIBXML_NONET | (\defined('LIBXML_COMPACT') ? LIBXML_COMPACT : 0))) {
             libxml_disable_entity_loader($disableEntities);
 
             throw new XmlParsingException(implode("\n", static::getXmlErrors($internalErrors)));
@@ -78,13 +78,13 @@ class XmlUtils
             libxml_clear_errors();
 
             $e = null;
-            if (is_callable($schemaOrCallable)) {
+            if (\is_callable($schemaOrCallable)) {
                 try {
-                    $valid = call_user_func($schemaOrCallable, $dom, $internalErrors);
+                    $valid = \call_user_func($schemaOrCallable, $dom, $internalErrors);
                 } catch (\Exception $e) {
                     $valid = false;
                 }
-            } elseif (!is_array($schemaOrCallable) && is_file((string) $schemaOrCallable)) {
+            } elseif (!\is_array($schemaOrCallable) && is_file((string) $schemaOrCallable)) {
                 $schemaSource = file_get_contents((string) $schemaOrCallable);
                 $valid = @$dom->schemaValidateSource($schemaSource);
             } else {
@@ -160,7 +160,7 @@ class XmlUtils
         $empty = true;
         $config = array();
         foreach ($element->attributes as $name => $node) {
-            if ($checkPrefix && !in_array((string) $node->prefix, array('', $prefix), true)) {
+            if ($checkPrefix && !\in_array((string) $node->prefix, array('', $prefix), true)) {
                 continue;
             }
             $config[$name] = static::phpize($node->value);
@@ -181,7 +181,7 @@ class XmlUtils
 
                 $key = $node->localName;
                 if (isset($config[$key])) {
-                    if (!is_array($config[$key]) || !is_int(key($config[$key]))) {
+                    if (!\is_array($config[$key]) || !\is_int(key($config[$key]))) {
                         $config[$key] = array($config[$key]);
                     }
                     $config[$key][] = $value;
@@ -195,7 +195,7 @@ class XmlUtils
 
         if (false !== $nodeValue) {
             $value = static::phpize($nodeValue);
-            if (count($config)) {
+            if (\count($config)) {
                 $config['value'] = $value;
             } else {
                 $config = $value;
diff --git a/src/Symfony/Component/Console/Application.php b/src/Symfony/Component/Console/Application.php
index 4020bd527f..3b74479c40 100644
--- a/src/Symfony/Component/Console/Application.php
+++ b/src/Symfony/Component/Console/Application.php
@@ -132,7 +132,7 @@ class Application
         };
         if ($phpHandler = set_exception_handler($renderException)) {
             restore_exception_handler();
-            if (!is_array($phpHandler) || !$phpHandler[0] instanceof ErrorHandler) {
+            if (!\is_array($phpHandler) || !$phpHandler[0] instanceof ErrorHandler) {
                 $debugHandler = true;
             } elseif ($debugHandler = $phpHandler[0]->setExceptionHandler($renderException)) {
                 $phpHandler[0]->setExceptionHandler($debugHandler);
@@ -225,7 +225,7 @@ class Application
             // the command name MUST be the first element of the input
             $command = $this->find($name);
         } catch (\Throwable $e) {
-            if (!($e instanceof CommandNotFoundException && !$e instanceof NamespaceNotFoundException) || 1 !== count($alternatives = $e->getAlternatives()) || !$input->isInteractive()) {
+            if (!($e instanceof CommandNotFoundException && !$e instanceof NamespaceNotFoundException) || 1 !== \count($alternatives = $e->getAlternatives()) || !$input->isInteractive()) {
                 if (null !== $this->dispatcher) {
                     $event = new ConsoleErrorEvent($input, $output, $e);
                     $this->dispatcher->dispatch(ConsoleEvents::ERROR, $event);
@@ -465,11 +465,11 @@ class Application
         }
 
         if (null === $command->getDefinition()) {
-            throw new LogicException(sprintf('Command class "%s" is not correctly initialized. You probably forgot to call the parent constructor.', get_class($command)));
+            throw new LogicException(sprintf('Command class "%s" is not correctly initialized. You probably forgot to call the parent constructor.', \get_class($command)));
         }
 
         if (!$command->getName()) {
-            throw new LogicException(sprintf('The command defined in "%s" cannot have an empty name.', get_class($command)));
+            throw new LogicException(sprintf('The command defined in "%s" cannot have an empty name.', \get_class($command)));
         }
 
         $this->commands[$command->getName()] = $command;
@@ -566,7 +566,7 @@ class Application
             $message = sprintf('There are no commands defined in the "%s" namespace.', $namespace);
 
             if ($alternatives = $this->findAlternatives($namespace, $allNamespaces)) {
-                if (1 == count($alternatives)) {
+                if (1 == \count($alternatives)) {
                     $message .= "\n\nDid you mean this?\n    ";
                 } else {
                     $message .= "\n\nDid you mean one of these?\n    ";
@@ -578,8 +578,8 @@ class Application
             throw new NamespaceNotFoundException($message, $alternatives);
         }
 
-        $exact = in_array($namespace, $namespaces, true);
-        if (count($namespaces) > 1 && !$exact) {
+        $exact = \in_array($namespace, $namespaces, true);
+        if (\count($namespaces) > 1 && !$exact) {
             throw new NamespaceNotFoundException(sprintf("The namespace \"%s\" is ambiguous.\nDid you mean one of these?\n%s", $namespace, $this->getAbbreviationSuggestions(array_values($namespaces))), array_values($namespaces));
         }
 
@@ -612,7 +612,7 @@ class Application
         }
 
         // if no commands matched or we just matched namespaces
-        if (empty($commands) || count(preg_grep('{^'.$expr.'$}i', $commands)) < 1) {
+        if (empty($commands) || \count(preg_grep('{^'.$expr.'$}i', $commands)) < 1) {
             if (false !== $pos = strrpos($name, ':')) {
                 // check if a namespace exists and contains commands
                 $this->findNamespace(substr($name, 0, $pos));
@@ -621,7 +621,7 @@ class Application
             $message = sprintf('Command "%s" is not defined.', $name);
 
             if ($alternatives = $this->findAlternatives($name, $allCommands)) {
-                if (1 == count($alternatives)) {
+                if (1 == \count($alternatives)) {
                     $message .= "\n\nDid you mean this?\n    ";
                 } else {
                     $message .= "\n\nDid you mean one of these?\n    ";
@@ -633,18 +633,18 @@ class Application
         }
 
         // filter out aliases for commands which are already on the list
-        if (count($commands) > 1) {
+        if (\count($commands) > 1) {
             $commandList = $this->commandLoader ? array_merge(array_flip($this->commandLoader->getNames()), $this->commands) : $this->commands;
             $commands = array_unique(array_filter($commands, function ($nameOrAlias) use ($commandList, $commands, &$aliases) {
                 $commandName = $commandList[$nameOrAlias] instanceof Command ? $commandList[$nameOrAlias]->getName() : $nameOrAlias;
                 $aliases[$nameOrAlias] = $commandName;
 
-                return $commandName === $nameOrAlias || !in_array($commandName, $commands);
+                return $commandName === $nameOrAlias || !\in_array($commandName, $commands);
             }));
         }
 
-        $exact = in_array($name, $commands, true) || isset($aliases[$name]);
-        if (count($commands) > 1 && !$exact) {
+        $exact = \in_array($name, $commands, true) || isset($aliases[$name]);
+        if (\count($commands) > 1 && !$exact) {
             $usableWidth = $this->terminal->getWidth() - 10;
             $abbrevs = array_values($commands);
             $maxLen = 0;
@@ -724,7 +724,7 @@ class Application
     {
         $abbrevs = array();
         foreach ($names as $name) {
-            for ($len = strlen($name); $len > 0; --$len) {
+            for ($len = \strlen($name); $len > 0; --$len) {
                 $abbrev = substr($name, 0, $len);
                 $abbrevs[$abbrev][] = $name;
             }
@@ -753,7 +753,7 @@ class Application
         do {
             $message = trim($e->getMessage());
             if ('' === $message || OutputInterface::VERBOSITY_VERBOSE <= $output->getVerbosity()) {
-                $title = sprintf('  [%s%s]  ', get_class($e), 0 !== ($code = $e->getCode()) ? ' ('.$code.')' : '');
+                $title = sprintf('  [%s%s]  ', \get_class($e), 0 !== ($code = $e->getCode()) ? ' ('.$code.')' : '');
                 $len = Helper::strlen($title);
             } else {
                 $len = 0;
@@ -793,7 +793,7 @@ class Application
                 // exception related properties
                 $trace = $e->getTrace();
 
-                for ($i = 0, $count = count($trace); $i < $count; ++$i) {
+                for ($i = 0, $count = \count($trace); $i < $count; ++$i) {
                     $class = isset($trace[$i]['class']) ? $trace[$i]['class'] : '';
                     $type = isset($trace[$i]['type']) ? $trace[$i]['type'] : '';
                     $function = $trace[$i]['function'];
@@ -821,7 +821,7 @@ class Application
 
         if (true === $input->hasParameterOption(array('--no-interaction', '-n'), true)) {
             $input->setInteractive(false);
-        } elseif (function_exists('posix_isatty')) {
+        } elseif (\function_exists('posix_isatty')) {
             $inputStream = null;
 
             if ($input instanceof StreamableInputInterface) {
@@ -1007,7 +1007,7 @@ class Application
         $parts = explode(':', $name);
         array_pop($parts);
 
-        return implode(':', null === $limit ? $parts : array_slice($parts, 0, $limit));
+        return implode(':', null === $limit ? $parts : \array_slice($parts, 0, $limit));
     }
 
     /**
@@ -1040,7 +1040,7 @@ class Application
                 }
 
                 $lev = levenshtein($subname, $parts[$i]);
-                if ($lev <= strlen($subname) / 3 || '' !== $subname && false !== strpos($parts[$i], $subname)) {
+                if ($lev <= \strlen($subname) / 3 || '' !== $subname && false !== strpos($parts[$i], $subname)) {
                     $alternatives[$collectionName] = $exists ? $alternatives[$collectionName] + $lev : $lev;
                 } elseif ($exists) {
                     $alternatives[$collectionName] += $threshold;
@@ -1050,7 +1050,7 @@ class Application
 
         foreach ($collection as $item) {
             $lev = levenshtein($name, $item);
-            if ($lev <= strlen($name) / 3 || false !== strpos($item, $name)) {
+            if ($lev <= \strlen($name) / 3 || false !== strpos($item, $name)) {
                 $alternatives[$item] = isset($alternatives[$item]) ? $alternatives[$item] - $lev : $lev;
             }
         }
@@ -1106,7 +1106,7 @@ class Application
             $line = $char;
         }
 
-        $lines[] = count($lines) ? str_pad($line, $width) : $line;
+        $lines[] = \count($lines) ? str_pad($line, $width) : $line;
 
         mb_convert_variables($encoding, 'utf8', $lines);
 
@@ -1127,7 +1127,7 @@ class Application
         $namespaces = array();
 
         foreach ($parts as $part) {
-            if (count($namespaces)) {
+            if (\count($namespaces)) {
                 $namespaces[] = end($namespaces).':'.$part;
             } else {
                 $namespaces[] = $part;
diff --git a/src/Symfony/Component/Console/Command/Command.php b/src/Symfony/Component/Console/Command/Command.php
index 62c3a834f6..aeaebe305a 100644
--- a/src/Symfony/Component/Console/Command/Command.php
+++ b/src/Symfony/Component/Console/Command/Command.php
@@ -55,7 +55,7 @@ class Command
      */
     public static function getDefaultName()
     {
-        $class = get_called_class();
+        $class = \get_called_class();
         $r = new \ReflectionProperty($class, 'defaultName');
 
         return $class === $r->class ? static::$defaultName : null;
@@ -217,7 +217,7 @@ class Command
         $this->initialize($input, $output);
 
         if (null !== $this->processTitle) {
-            if (function_exists('cli_set_process_title')) {
+            if (\function_exists('cli_set_process_title')) {
                 if (!@cli_set_process_title($this->processTitle)) {
                     if ('Darwin' === PHP_OS) {
                         $output->writeln('<comment>Running "cli_set_process_title" as an unprivileged user is not supported on MacOS.</comment>', OutputInterface::VERBOSITY_VERY_VERBOSE);
@@ -225,7 +225,7 @@ class Command
                         cli_set_process_title($this->processTitle);
                     }
                 }
-            } elseif (function_exists('setproctitle')) {
+            } elseif (\function_exists('setproctitle')) {
                 setproctitle($this->processTitle);
             } elseif (OutputInterface::VERBOSITY_VERY_VERBOSE === $output->getVerbosity()) {
                 $output->writeln('<comment>Install the proctitle PECL to be able to change the process title.</comment>');
@@ -246,7 +246,7 @@ class Command
         $input->validate();
 
         if ($this->code) {
-            $statusCode = call_user_func($this->code, $input, $output);
+            $statusCode = \call_user_func($this->code, $input, $output);
         } else {
             $statusCode = $this->execute($input, $output);
         }
@@ -542,7 +542,7 @@ class Command
      */
     public function setAliases($aliases)
     {
-        if (!is_array($aliases) && !$aliases instanceof \Traversable) {
+        if (!\is_array($aliases) && !$aliases instanceof \Traversable) {
             throw new InvalidArgumentException('$aliases must be an array or an instance of \Traversable');
         }
 
diff --git a/src/Symfony/Component/Console/Descriptor/Descriptor.php b/src/Symfony/Component/Console/Descriptor/Descriptor.php
index fe169cb48a..f0794b3a17 100644
--- a/src/Symfony/Component/Console/Descriptor/Descriptor.php
+++ b/src/Symfony/Component/Console/Descriptor/Descriptor.php
@@ -55,7 +55,7 @@ abstract class Descriptor implements DescriptorInterface
                 $this->describeApplication($object, $options);
                 break;
             default:
-                throw new InvalidArgumentException(sprintf('Object of type "%s" is not describable.', get_class($object)));
+                throw new InvalidArgumentException(sprintf('Object of type "%s" is not describable.', \get_class($object)));
         }
     }
 
diff --git a/src/Symfony/Component/Console/Descriptor/MarkdownDescriptor.php b/src/Symfony/Component/Console/Descriptor/MarkdownDescriptor.php
index d52ba55342..6d8399f922 100644
--- a/src/Symfony/Component/Console/Descriptor/MarkdownDescriptor.php
+++ b/src/Symfony/Component/Console/Descriptor/MarkdownDescriptor.php
@@ -88,7 +88,7 @@ class MarkdownDescriptor extends Descriptor
      */
     protected function describeInputDefinition(InputDefinition $definition, array $options = array())
     {
-        if ($showArguments = count($definition->getArguments()) > 0) {
+        if ($showArguments = \count($definition->getArguments()) > 0) {
             $this->write('### Arguments');
             foreach ($definition->getArguments() as $argument) {
                 $this->write("\n\n");
@@ -96,7 +96,7 @@ class MarkdownDescriptor extends Descriptor
             }
         }
 
-        if (count($definition->getOptions()) > 0) {
+        if (\count($definition->getOptions()) > 0) {
             if ($showArguments) {
                 $this->write("\n\n");
             }
diff --git a/src/Symfony/Component/Console/Descriptor/TextDescriptor.php b/src/Symfony/Component/Console/Descriptor/TextDescriptor.php
index e44cd55b8b..9361b10986 100644
--- a/src/Symfony/Component/Console/Descriptor/TextDescriptor.php
+++ b/src/Symfony/Component/Console/Descriptor/TextDescriptor.php
@@ -33,14 +33,14 @@ class TextDescriptor extends Descriptor
      */
     protected function describeInputArgument(InputArgument $argument, array $options = array())
     {
-        if (null !== $argument->getDefault() && (!is_array($argument->getDefault()) || count($argument->getDefault()))) {
+        if (null !== $argument->getDefault() && (!\is_array($argument->getDefault()) || \count($argument->getDefault()))) {
             $default = sprintf('<comment> [default: %s]</comment>', $this->formatDefaultValue($argument->getDefault()));
         } else {
             $default = '';
         }
 
         $totalWidth = isset($options['total_width']) ? $options['total_width'] : Helper::strlen($argument->getName());
-        $spacingWidth = $totalWidth - strlen($argument->getName());
+        $spacingWidth = $totalWidth - \strlen($argument->getName());
 
         $this->writeText(sprintf('  <info>%s</info>  %s%s%s',
             $argument->getName(),
@@ -56,7 +56,7 @@ class TextDescriptor extends Descriptor
      */
     protected function describeInputOption(InputOption $option, array $options = array())
     {
-        if ($option->acceptValue() && null !== $option->getDefault() && (!is_array($option->getDefault()) || count($option->getDefault()))) {
+        if ($option->acceptValue() && null !== $option->getDefault() && (!\is_array($option->getDefault()) || \count($option->getDefault()))) {
             $default = sprintf('<comment> [default: %s]</comment>', $this->formatDefaultValue($option->getDefault()));
         } else {
             $default = '';
@@ -117,7 +117,7 @@ class TextDescriptor extends Descriptor
 
             $this->writeText('<comment>Options:</comment>', $options);
             foreach ($definition->getOptions() as $option) {
-                if (strlen($option->getShortcut()) > 1) {
+                if (\strlen($option->getShortcut()) > 1) {
                     $laterOptions[] = $option;
                     continue;
                 }
@@ -284,11 +284,11 @@ class TextDescriptor extends Descriptor
             return 'INF';
         }
 
-        if (is_string($default)) {
+        if (\is_string($default)) {
             $default = OutputFormatter::escape($default);
-        } elseif (is_array($default)) {
+        } elseif (\is_array($default)) {
             foreach ($default as $key => $value) {
-                if (is_string($value)) {
+                if (\is_string($value)) {
                     $default[$key] = OutputFormatter::escape($value);
                 }
             }
diff --git a/src/Symfony/Component/Console/Descriptor/XmlDescriptor.php b/src/Symfony/Component/Console/Descriptor/XmlDescriptor.php
index a2eaca3b18..d0c6abddb4 100644
--- a/src/Symfony/Component/Console/Descriptor/XmlDescriptor.php
+++ b/src/Symfony/Component/Console/Descriptor/XmlDescriptor.php
@@ -200,7 +200,7 @@ class XmlDescriptor extends Descriptor
         $descriptionXML->appendChild($dom->createTextNode($argument->getDescription()));
 
         $objectXML->appendChild($defaultsXML = $dom->createElement('defaults'));
-        $defaults = is_array($argument->getDefault()) ? $argument->getDefault() : (is_bool($argument->getDefault()) ? array(var_export($argument->getDefault(), true)) : ($argument->getDefault() ? array($argument->getDefault()) : array()));
+        $defaults = \is_array($argument->getDefault()) ? $argument->getDefault() : (\is_bool($argument->getDefault()) ? array(var_export($argument->getDefault(), true)) : ($argument->getDefault() ? array($argument->getDefault()) : array()));
         foreach ($defaults as $default) {
             $defaultsXML->appendChild($defaultXML = $dom->createElement('default'));
             $defaultXML->appendChild($dom->createTextNode($default));
@@ -229,7 +229,7 @@ class XmlDescriptor extends Descriptor
         $descriptionXML->appendChild($dom->createTextNode($option->getDescription()));
 
         if ($option->acceptValue()) {
-            $defaults = is_array($option->getDefault()) ? $option->getDefault() : (is_bool($option->getDefault()) ? array(var_export($option->getDefault(), true)) : ($option->getDefault() ? array($option->getDefault()) : array()));
+            $defaults = \is_array($option->getDefault()) ? $option->getDefault() : (\is_bool($option->getDefault()) ? array(var_export($option->getDefault(), true)) : ($option->getDefault() ? array($option->getDefault()) : array()));
             $objectXML->appendChild($defaultsXML = $dom->createElement('defaults'));
 
             if (!empty($defaults)) {
diff --git a/src/Symfony/Component/Console/Event/ConsoleErrorEvent.php b/src/Symfony/Component/Console/Event/ConsoleErrorEvent.php
index 3665da77d9..25d9b88127 100644
--- a/src/Symfony/Component/Console/Event/ConsoleErrorEvent.php
+++ b/src/Symfony/Component/Console/Event/ConsoleErrorEvent.php
@@ -53,6 +53,6 @@ final class ConsoleErrorEvent extends ConsoleEvent
 
     public function getExitCode(): int
     {
-        return null !== $this->exitCode ? $this->exitCode : (is_int($this->error->getCode()) && 0 !== $this->error->getCode() ? $this->error->getCode() : 1);
+        return null !== $this->exitCode ? $this->exitCode : (\is_int($this->error->getCode()) && 0 !== $this->error->getCode() ? $this->error->getCode() : 1);
     }
 }
diff --git a/src/Symfony/Component/Console/Formatter/OutputFormatter.php b/src/Symfony/Component/Console/Formatter/OutputFormatter.php
index a78bd95205..eebac82e70 100644
--- a/src/Symfony/Component/Console/Formatter/OutputFormatter.php
+++ b/src/Symfony/Component/Console/Formatter/OutputFormatter.php
@@ -50,10 +50,10 @@ class OutputFormatter implements OutputFormatterInterface
     public static function escapeTrailingBackslash($text)
     {
         if ('\\' === substr($text, -1)) {
-            $len = strlen($text);
+            $len = \strlen($text);
             $text = rtrim($text, '\\');
             $text = str_replace("\0", '', $text);
-            $text .= str_repeat("\0", $len - strlen($text));
+            $text .= str_repeat("\0", $len - \strlen($text));
         }
 
         return $text;
@@ -145,7 +145,7 @@ class OutputFormatter implements OutputFormatterInterface
 
             // add the text up to the next tag
             $output .= $this->applyCurrentStyle(substr($message, $offset, $pos - $offset));
-            $offset = $pos + strlen($text);
+            $offset = $pos + \strlen($text);
 
             // opening tag?
             if ($open = '/' != $text[1]) {
@@ -225,6 +225,6 @@ class OutputFormatter implements OutputFormatterInterface
      */
     private function applyCurrentStyle(string $text): string
     {
-        return $this->isDecorated() && strlen($text) > 0 ? $this->styleStack->getCurrent()->apply($text) : $text;
+        return $this->isDecorated() && \strlen($text) > 0 ? $this->styleStack->getCurrent()->apply($text) : $text;
     }
 }
diff --git a/src/Symfony/Component/Console/Formatter/OutputFormatterStyle.php b/src/Symfony/Component/Console/Formatter/OutputFormatterStyle.php
index 900f2ef31b..d09994f225 100644
--- a/src/Symfony/Component/Console/Formatter/OutputFormatterStyle.php
+++ b/src/Symfony/Component/Console/Formatter/OutputFormatterStyle.php
@@ -69,7 +69,7 @@ class OutputFormatterStyle implements OutputFormatterStyleInterface
         if (null !== $background) {
             $this->setBackground($background);
         }
-        if (count($options)) {
+        if (\count($options)) {
             $this->setOptions($options);
         }
     }
@@ -143,7 +143,7 @@ class OutputFormatterStyle implements OutputFormatterStyleInterface
             ));
         }
 
-        if (!in_array(static::$availableOptions[$option], $this->options)) {
+        if (!\in_array(static::$availableOptions[$option], $this->options)) {
             $this->options[] = static::$availableOptions[$option];
         }
     }
@@ -203,14 +203,14 @@ class OutputFormatterStyle implements OutputFormatterStyleInterface
             $setCodes[] = $this->background['set'];
             $unsetCodes[] = $this->background['unset'];
         }
-        if (count($this->options)) {
+        if (\count($this->options)) {
             foreach ($this->options as $option) {
                 $setCodes[] = $option['set'];
                 $unsetCodes[] = $option['unset'];
             }
         }
 
-        if (0 === count($setCodes)) {
+        if (0 === \count($setCodes)) {
             return $text;
         }
 
diff --git a/src/Symfony/Component/Console/Formatter/OutputFormatterStyleStack.php b/src/Symfony/Component/Console/Formatter/OutputFormatterStyleStack.php
index b0d3383d50..7ca93035b6 100644
--- a/src/Symfony/Component/Console/Formatter/OutputFormatterStyleStack.php
+++ b/src/Symfony/Component/Console/Formatter/OutputFormatterStyleStack.php
@@ -67,7 +67,7 @@ class OutputFormatterStyleStack implements ResetInterface
 
         foreach (array_reverse($this->styles, true) as $index => $stackedStyle) {
             if ($style->apply('') === $stackedStyle->apply('')) {
-                $this->styles = array_slice($this->styles, 0, $index);
+                $this->styles = \array_slice($this->styles, 0, $index);
 
                 return $stackedStyle;
             }
@@ -87,7 +87,7 @@ class OutputFormatterStyleStack implements ResetInterface
             return $this->emptyStyle;
         }
 
-        return $this->styles[count($this->styles) - 1];
+        return $this->styles[\count($this->styles) - 1];
     }
 
     /**
diff --git a/src/Symfony/Component/Console/Helper/DebugFormatterHelper.php b/src/Symfony/Component/Console/Helper/DebugFormatterHelper.php
index 1119b795c8..f5393edee3 100644
--- a/src/Symfony/Component/Console/Helper/DebugFormatterHelper.php
+++ b/src/Symfony/Component/Console/Helper/DebugFormatterHelper.php
@@ -35,7 +35,7 @@ class DebugFormatterHelper extends Helper
      */
     public function start($id, $message, $prefix = 'RUN')
     {
-        $this->started[$id] = array('border' => ++$this->count % count($this->colors));
+        $this->started[$id] = array('border' => ++$this->count % \count($this->colors));
 
         return sprintf("%s<bg=blue;fg=white> %s </> <fg=blue>%s</>\n", $this->getBorder($id), $prefix, $message);
     }
diff --git a/src/Symfony/Component/Console/Helper/FormatterHelper.php b/src/Symfony/Component/Console/Helper/FormatterHelper.php
index 6a48a77f26..79ab2849e5 100644
--- a/src/Symfony/Component/Console/Helper/FormatterHelper.php
+++ b/src/Symfony/Component/Console/Helper/FormatterHelper.php
@@ -45,7 +45,7 @@ class FormatterHelper extends Helper
      */
     public function formatBlock($messages, $style, $large = false)
     {
-        if (!is_array($messages)) {
+        if (!\is_array($messages)) {
             $messages = array($messages);
         }
 
diff --git a/src/Symfony/Component/Console/Helper/Helper.php b/src/Symfony/Component/Console/Helper/Helper.php
index 0954bad6b2..5090185526 100644
--- a/src/Symfony/Component/Console/Helper/Helper.php
+++ b/src/Symfony/Component/Console/Helper/Helper.php
@@ -48,7 +48,7 @@ abstract class Helper implements HelperInterface
     public static function strlen($string)
     {
         if (false === $encoding = mb_detect_encoding($string, null, true)) {
-            return strlen($string);
+            return \strlen($string);
         }
 
         return mb_strwidth($string, $encoding);
@@ -89,9 +89,9 @@ abstract class Helper implements HelperInterface
         foreach ($timeFormats as $index => $format) {
             if ($secs >= $format[0]) {
                 if ((isset($timeFormats[$index + 1]) && $secs < $timeFormats[$index + 1][0])
-                    || $index == count($timeFormats) - 1
+                    || $index == \count($timeFormats) - 1
                 ) {
-                    if (2 == count($format)) {
+                    if (2 == \count($format)) {
                         return $format[1];
                     }
 
diff --git a/src/Symfony/Component/Console/Helper/HelperSet.php b/src/Symfony/Component/Console/Helper/HelperSet.php
index 24ce18fb49..4c44b05f56 100644
--- a/src/Symfony/Component/Console/Helper/HelperSet.php
+++ b/src/Symfony/Component/Console/Helper/HelperSet.php
@@ -33,7 +33,7 @@ class HelperSet implements \IteratorAggregate
     public function __construct(array $helpers = array())
     {
         foreach ($helpers as $alias => $helper) {
-            $this->set($helper, is_int($alias) ? null : $alias);
+            $this->set($helper, \is_int($alias) ? null : $alias);
         }
     }
 
diff --git a/src/Symfony/Component/Console/Helper/ProcessHelper.php b/src/Symfony/Component/Console/Helper/ProcessHelper.php
index 4d88d7041c..e0720c134e 100644
--- a/src/Symfony/Component/Console/Helper/ProcessHelper.php
+++ b/src/Symfony/Component/Console/Helper/ProcessHelper.php
@@ -136,7 +136,7 @@ class ProcessHelper extends Helper
             $output->write($formatter->progress(spl_object_hash($process), $this->escapeString($buffer), Process::ERR === $type));
 
             if (null !== $callback) {
-                call_user_func($callback, $type, $buffer);
+                \call_user_func($callback, $type, $buffer);
             }
         };
     }
diff --git a/src/Symfony/Component/Console/Helper/ProgressBar.php b/src/Symfony/Component/Console/Helper/ProgressBar.php
index a9d0786761..87fed69cf8 100644
--- a/src/Symfony/Component/Console/Helper/ProgressBar.php
+++ b/src/Symfony/Component/Console/Helper/ProgressBar.php
@@ -496,7 +496,7 @@ final class ProgressBar
         $regex = "{%([a-z\-_]+)(?:\:([^%]+))?%}i";
         $callback = function ($matches) {
             if ($formatter = $this::getPlaceholderFormatterDefinition($matches[1])) {
-                $text = call_user_func($formatter, $this, $this->output);
+                $text = \call_user_func($formatter, $this, $this->output);
             } elseif (isset($this->messages[$matches[1]])) {
                 $text = $this->messages[$matches[1]];
             } else {
diff --git a/src/Symfony/Component/Console/Helper/ProgressIndicator.php b/src/Symfony/Component/Console/Helper/ProgressIndicator.php
index e6094647fa..fe516df030 100644
--- a/src/Symfony/Component/Console/Helper/ProgressIndicator.php
+++ b/src/Symfony/Component/Console/Helper/ProgressIndicator.php
@@ -53,7 +53,7 @@ class ProgressIndicator
 
         $indicatorValues = array_values($indicatorValues);
 
-        if (2 > count($indicatorValues)) {
+        if (2 > \count($indicatorValues)) {
             throw new InvalidArgumentException('Must have at least 2 indicator value characters.');
         }
 
@@ -196,7 +196,7 @@ class ProgressIndicator
 
         $this->overwrite(preg_replace_callback("{%([a-z\-_]+)(?:\:([^%]+))?%}i", function ($matches) use ($self) {
             if ($formatter = $self::getPlaceholderFormatterDefinition($matches[1])) {
-                return call_user_func($formatter, $self);
+                return \call_user_func($formatter, $self);
             }
 
             return $matches[0];
@@ -239,7 +239,7 @@ class ProgressIndicator
     {
         return array(
             'indicator' => function (ProgressIndicator $indicator) {
-                return $indicator->indicatorValues[$indicator->indicatorCurrent % count($indicator->indicatorValues)];
+                return $indicator->indicatorValues[$indicator->indicatorCurrent % \count($indicator->indicatorValues)];
             },
             'message' => function (ProgressIndicator $indicator) {
                 return $indicator->message;
diff --git a/src/Symfony/Component/Console/Helper/QuestionHelper.php b/src/Symfony/Component/Console/Helper/QuestionHelper.php
index 46e1383e78..d16a7fff84 100644
--- a/src/Symfony/Component/Console/Helper/QuestionHelper.php
+++ b/src/Symfony/Component/Console/Helper/QuestionHelper.php
@@ -120,10 +120,10 @@ class QuestionHelper extends Helper
                 $ret = trim($ret);
             }
         } else {
-            $ret = trim($this->autocomplete($output, $question, $inputStream, is_array($autocomplete) ? $autocomplete : iterator_to_array($autocomplete, false)));
+            $ret = trim($this->autocomplete($output, $question, $inputStream, \is_array($autocomplete) ? $autocomplete : iterator_to_array($autocomplete, false)));
         }
 
-        $ret = strlen($ret) > 0 ? $ret : $question->getDefault();
+        $ret = \strlen($ret) > 0 ? $ret : $question->getDefault();
 
         if ($normalizer = $question->getNormalizer()) {
             return $normalizer($ret);
@@ -184,7 +184,7 @@ class QuestionHelper extends Helper
         $i = 0;
         $ofs = -1;
         $matches = $autocomplete;
-        $numMatches = count($matches);
+        $numMatches = \count($matches);
 
         $sttyMode = shell_exec('stty -g');
 
@@ -209,7 +209,7 @@ class QuestionHelper extends Helper
                 if (0 === $i) {
                     $ofs = -1;
                     $matches = $autocomplete;
-                    $numMatches = count($matches);
+                    $numMatches = \count($matches);
                 } else {
                     $numMatches = 0;
                 }
@@ -233,13 +233,13 @@ class QuestionHelper extends Helper
                     $ofs += ('A' === $c[2]) ? -1 : 1;
                     $ofs = ($numMatches + $ofs) % $numMatches;
                 }
-            } elseif (ord($c) < 32) {
+            } elseif (\ord($c) < 32) {
                 if ("\t" === $c || "\n" === $c) {
                     if ($numMatches > 0 && -1 !== $ofs) {
                         $ret = $matches[$ofs];
                         // Echo out remaining chars for current match
                         $output->write(substr($ret, $i));
-                        $i = strlen($ret);
+                        $i = \strlen($ret);
                     }
 
                     if ("\n" === $c) {
@@ -366,7 +366,7 @@ class QuestionHelper extends Helper
             }
 
             try {
-                return call_user_func($question->getValidator(), $interviewer());
+                return \call_user_func($question->getValidator(), $interviewer());
             } catch (RuntimeException $e) {
                 throw $e;
             } catch (\Exception $error) {
diff --git a/src/Symfony/Component/Console/Helper/Table.php b/src/Symfony/Component/Console/Helper/Table.php
index 25b2dabceb..39980357c7 100644
--- a/src/Symfony/Component/Console/Helper/Table.php
+++ b/src/Symfony/Component/Console/Helper/Table.php
@@ -225,7 +225,7 @@ class Table
     public function setHeaders(array $headers)
     {
         $headers = array_values($headers);
-        if (!empty($headers) && !is_array($headers[0])) {
+        if (!empty($headers) && !\is_array($headers[0])) {
             $headers = array($headers);
         }
 
@@ -258,7 +258,7 @@ class Table
             return $this;
         }
 
-        if (!is_array($row)) {
+        if (!\is_array($row)) {
             throw new InvalidArgumentException('A row must be an array or a TableSeparator instance.');
         }
 
@@ -436,7 +436,7 @@ class Table
     {
         $rowContent = $this->renderColumnSeparator(self::BORDER_OUTSIDE);
         $columns = $this->getRowColumns($row);
-        $last = count($columns) - 1;
+        $last = \count($columns) - 1;
         foreach ($columns as $i => $column) {
             $rowContent .= $this->renderCell($row, $column, $cellFormat);
             $rowContent .= $this->renderColumnSeparator($last === $i ? self::BORDER_OUTSIDE : self::BORDER_INSIDE);
@@ -460,7 +460,7 @@ class Table
 
         // str_pad won't work properly with multi-byte strings, we need to fix the padding
         if (false !== $encoding = mb_detect_encoding($cell, null, true)) {
-            $width += strlen($cell) - mb_strwidth($cell, $encoding);
+            $width += \strlen($cell) - mb_strwidth($cell, $encoding);
         }
 
         $style = $this->getColumnStyle($column);
@@ -495,7 +495,7 @@ class Table
     private function buildTableRows($rows)
     {
         $unmergedRows = array();
-        for ($rowKey = 0; $rowKey < count($rows); ++$rowKey) {
+        for ($rowKey = 0; $rowKey < \count($rows); ++$rowKey) {
             $rows = $this->fillNextRows($rows, $rowKey);
 
             // Remove any new line breaks and replace it with a new line
@@ -532,7 +532,7 @@ class Table
 
     private function calculateRowCount(): int
     {
-        $numberOfRows = count(iterator_to_array($this->buildTableRows(array_merge($this->headers, array(new TableSeparator()), $this->rows))));
+        $numberOfRows = \count(iterator_to_array($this->buildTableRows(array_merge($this->headers, array(new TableSeparator()), $this->rows))));
 
         if ($this->headers) {
             ++$numberOfRows; // Add row for header separator
@@ -552,15 +552,15 @@ class Table
     {
         $unmergedRows = array();
         foreach ($rows[$line] as $column => $cell) {
-            if (null !== $cell && !$cell instanceof TableCell && !is_scalar($cell) && !(is_object($cell) && method_exists($cell, '__toString'))) {
-                throw new InvalidArgumentException(sprintf('A cell must be a TableCell, a scalar or an object implementing __toString, %s given.', gettype($cell)));
+            if (null !== $cell && !$cell instanceof TableCell && !is_scalar($cell) && !(\is_object($cell) && method_exists($cell, '__toString'))) {
+                throw new InvalidArgumentException(sprintf('A cell must be a TableCell, a scalar or an object implementing __toString, %s given.', \gettype($cell)));
             }
             if ($cell instanceof TableCell && $cell->getRowspan() > 1) {
                 $nbLines = $cell->getRowspan() - 1;
                 $lines = array($cell);
                 if (strstr($cell, "\n")) {
                     $lines = explode("\n", str_replace("\n", "<fg=default;bg=default>\n</>", $cell));
-                    $nbLines = count($lines) > $nbLines ? substr_count($cell, "\n") : $nbLines;
+                    $nbLines = \count($lines) > $nbLines ? substr_count($cell, "\n") : $nbLines;
 
                     $rows[$line][$column] = new TableCell($lines[0], array('colspan' => $cell->getColspan()));
                     unset($lines[0]);
@@ -580,7 +580,7 @@ class Table
 
         foreach ($unmergedRows as $unmergedRowKey => $unmergedRow) {
             // we need to know if $unmergedRow will be merged or inserted into $rows
-            if (isset($rows[$unmergedRowKey]) && is_array($rows[$unmergedRowKey]) && ($this->getNumberOfColumns($rows[$unmergedRowKey]) + $this->getNumberOfColumns($unmergedRows[$unmergedRowKey]) <= $this->numberOfColumns)) {
+            if (isset($rows[$unmergedRowKey]) && \is_array($rows[$unmergedRowKey]) && ($this->getNumberOfColumns($rows[$unmergedRowKey]) + $this->getNumberOfColumns($unmergedRows[$unmergedRowKey]) <= $this->numberOfColumns)) {
                 foreach ($unmergedRow as $cellKey => $cell) {
                     // insert cell into row at cellKey position
                     array_splice($rows[$unmergedRowKey], $cellKey, 0, array($cell));
@@ -636,7 +636,7 @@ class Table
      */
     private function getNumberOfColumns(array $row): int
     {
-        $columns = count($row);
+        $columns = \count($row);
         foreach ($row as $column) {
             $columns += $column instanceof TableCell ? ($column->getColspan() - 1) : 0;
         }
@@ -688,13 +688,13 @@ class Table
                 $lengths[] = $this->getCellWidth($row, $column);
             }
 
-            $this->effectiveColumnWidths[$column] = max($lengths) + strlen($this->style->getCellRowContentFormat()) - 2;
+            $this->effectiveColumnWidths[$column] = max($lengths) + \strlen($this->style->getCellRowContentFormat()) - 2;
         }
     }
 
     private function getColumnSeparatorWidth(): int
     {
-        return strlen(sprintf($this->style->getBorderFormat(), $this->style->getBorderChars()[3]));
+        return \strlen(sprintf($this->style->getBorderFormat(), $this->style->getBorderChars()[3]));
     }
 
     private function getCellWidth(array $row, int $column): int
diff --git a/src/Symfony/Component/Console/Helper/TableStyle.php b/src/Symfony/Component/Console/Helper/TableStyle.php
index c268f5f030..f02aa59311 100644
--- a/src/Symfony/Component/Console/Helper/TableStyle.php
+++ b/src/Symfony/Component/Console/Helper/TableStyle.php
@@ -413,7 +413,7 @@ class TableStyle
      */
     public function setPadType($padType)
     {
-        if (!in_array($padType, array(STR_PAD_LEFT, STR_PAD_RIGHT, STR_PAD_BOTH), true)) {
+        if (!\in_array($padType, array(STR_PAD_LEFT, STR_PAD_RIGHT, STR_PAD_BOTH), true)) {
             throw new InvalidArgumentException('Invalid padding type. Expected one of (STR_PAD_LEFT, STR_PAD_RIGHT, STR_PAD_BOTH).');
         }
 
diff --git a/src/Symfony/Component/Console/Input/ArgvInput.php b/src/Symfony/Component/Console/Input/ArgvInput.php
index 14276ba317..da268677a6 100644
--- a/src/Symfony/Component/Console/Input/ArgvInput.php
+++ b/src/Symfony/Component/Console/Input/ArgvInput.php
@@ -97,7 +97,7 @@ class ArgvInput extends Input
     {
         $name = substr($token, 1);
 
-        if (strlen($name) > 1) {
+        if (\strlen($name) > 1) {
             if ($this->definition->hasShortcut($name[0]) && $this->definition->getOptionForShortcut($name[0])->acceptValue()) {
                 // an option with a value (with no space)
                 $this->addShortOption($name[0], substr($name, 1));
@@ -118,7 +118,7 @@ class ArgvInput extends Input
      */
     private function parseShortOptionSet($name)
     {
-        $len = strlen($name);
+        $len = \strlen($name);
         for ($i = 0; $i < $len; ++$i) {
             if (!$this->definition->hasShortcut($name[$i])) {
                 throw new RuntimeException(sprintf('The "-%s" option does not exist.', $name[$i]));
@@ -145,7 +145,7 @@ class ArgvInput extends Input
         $name = substr($token, 2);
 
         if (false !== $pos = strpos($name, '=')) {
-            if (0 === strlen($value = substr($name, $pos + 1))) {
+            if (0 === \strlen($value = substr($name, $pos + 1))) {
                 array_unshift($this->parsed, $value);
             }
             $this->addLongOption(substr($name, 0, $pos), $value);
@@ -163,7 +163,7 @@ class ArgvInput extends Input
      */
     private function parseArgument($token)
     {
-        $c = count($this->arguments);
+        $c = \count($this->arguments);
 
         // if input is expecting another argument, add it
         if ($this->definition->hasArgument($c)) {
@@ -178,7 +178,7 @@ class ArgvInput extends Input
         // unexpected argument
         } else {
             $all = $this->definition->getArguments();
-            if (count($all)) {
+            if (\count($all)) {
                 throw new RuntimeException(sprintf('Too many arguments, expected arguments "%s".', implode('" "', array_keys($all))));
             }
 
@@ -223,11 +223,11 @@ class ArgvInput extends Input
             throw new RuntimeException(sprintf('The "--%s" option does not accept a value.', $name));
         }
 
-        if (in_array($value, array('', null), true) && $option->acceptValue() && count($this->parsed)) {
+        if (\in_array($value, array('', null), true) && $option->acceptValue() && \count($this->parsed)) {
             // if option accepts an optional or mandatory argument
             // let's see if there is one provided
             $next = array_shift($this->parsed);
-            if ((isset($next[0]) && '-' !== $next[0]) || in_array($next, array('', null), true)) {
+            if ((isset($next[0]) && '-' !== $next[0]) || \in_array($next, array('', null), true)) {
                 $value = $next;
             } else {
                 array_unshift($this->parsed, $next);
@@ -298,7 +298,7 @@ class ArgvInput extends Input
         $values = (array) $values;
         $tokens = $this->tokens;
 
-        while (0 < count($tokens)) {
+        while (0 < \count($tokens)) {
             $token = array_shift($tokens);
             if ($onlyParams && '--' === $token) {
                 return $default;
@@ -313,7 +313,7 @@ class ArgvInput extends Input
                 //   For short options, test for '-o' at beginning
                 $leading = 0 === strpos($value, '--') ? $value.'=' : $value;
                 if ('' !== $leading && 0 === strpos($token, $leading)) {
-                    return substr($token, strlen($leading));
+                    return substr($token, \strlen($leading));
                 }
             }
         }
diff --git a/src/Symfony/Component/Console/Input/ArrayInput.php b/src/Symfony/Component/Console/Input/ArrayInput.php
index 595a8a0e8c..8b6917fc7c 100644
--- a/src/Symfony/Component/Console/Input/ArrayInput.php
+++ b/src/Symfony/Component/Console/Input/ArrayInput.php
@@ -56,7 +56,7 @@ class ArrayInput extends Input
         $values = (array) $values;
 
         foreach ($this->parameters as $k => $v) {
-            if (!is_int($k)) {
+            if (!\is_int($k)) {
                 $v = $k;
             }
 
@@ -64,7 +64,7 @@ class ArrayInput extends Input
                 return false;
             }
 
-            if (in_array($v, $values)) {
+            if (\in_array($v, $values)) {
                 return true;
             }
         }
@@ -80,15 +80,15 @@ class ArrayInput extends Input
         $values = (array) $values;
 
         foreach ($this->parameters as $k => $v) {
-            if ($onlyParams && ('--' === $k || (is_int($k) && '--' === $v))) {
+            if ($onlyParams && ('--' === $k || (\is_int($k) && '--' === $v))) {
                 return $default;
             }
 
-            if (is_int($k)) {
-                if (in_array($v, $values)) {
+            if (\is_int($k)) {
+                if (\in_array($v, $values)) {
                     return true;
                 }
-            } elseif (in_array($k, $values)) {
+            } elseif (\in_array($k, $values)) {
                 return $v;
             }
         }
@@ -106,7 +106,7 @@ class ArrayInput extends Input
         $params = array();
         foreach ($this->parameters as $param => $val) {
             if ($param && '-' === $param[0]) {
-                if (is_array($val)) {
+                if (\is_array($val)) {
                     foreach ($val as $v) {
                         $params[] = $param.('' != $v ? '='.$this->escapeToken($v) : '');
                     }
@@ -114,7 +114,7 @@ class ArrayInput extends Input
                     $params[] = $param.('' != $val ? '='.$this->escapeToken($val) : '');
                 }
             } else {
-                $params[] = is_array($val) ? implode(' ', array_map(array($this, 'escapeToken'), $val)) : $this->escapeToken($val);
+                $params[] = \is_array($val) ? implode(' ', array_map(array($this, 'escapeToken'), $val)) : $this->escapeToken($val);
             }
         }
 
diff --git a/src/Symfony/Component/Console/Input/Input.php b/src/Symfony/Component/Console/Input/Input.php
index 4141325219..fa5644d1fd 100644
--- a/src/Symfony/Component/Console/Input/Input.php
+++ b/src/Symfony/Component/Console/Input/Input.php
@@ -72,7 +72,7 @@ abstract class Input implements InputInterface, StreamableInputInterface
             return !array_key_exists($argument, $givenArguments) && $definition->getArgument($argument)->isRequired();
         });
 
-        if (count($missingArguments) > 0) {
+        if (\count($missingArguments) > 0) {
             throw new RuntimeException(sprintf('Not enough arguments (missing: "%s").', implode(', ', $missingArguments)));
         }
     }
diff --git a/src/Symfony/Component/Console/Input/InputArgument.php b/src/Symfony/Component/Console/Input/InputArgument.php
index b5cbbaf1b4..409c4c4a92 100644
--- a/src/Symfony/Component/Console/Input/InputArgument.php
+++ b/src/Symfony/Component/Console/Input/InputArgument.php
@@ -99,7 +99,7 @@ class InputArgument
         if ($this->isArray()) {
             if (null === $default) {
                 $default = array();
-            } elseif (!is_array($default)) {
+            } elseif (!\is_array($default)) {
                 throw new LogicException('A default value for an array argument must be an array.');
             }
         }
diff --git a/src/Symfony/Component/Console/Input/InputDefinition.php b/src/Symfony/Component/Console/Input/InputDefinition.php
index 6059b3170b..dc9f8b241f 100644
--- a/src/Symfony/Component/Console/Input/InputDefinition.php
+++ b/src/Symfony/Component/Console/Input/InputDefinition.php
@@ -135,7 +135,7 @@ class InputDefinition
             throw new InvalidArgumentException(sprintf('The "%s" argument does not exist.', $name));
         }
 
-        $arguments = is_int($name) ? array_values($this->arguments) : $this->arguments;
+        $arguments = \is_int($name) ? array_values($this->arguments) : $this->arguments;
 
         return $arguments[$name];
     }
@@ -149,7 +149,7 @@ class InputDefinition
      */
     public function hasArgument($name)
     {
-        $arguments = is_int($name) ? array_values($this->arguments) : $this->arguments;
+        $arguments = \is_int($name) ? array_values($this->arguments) : $this->arguments;
 
         return isset($arguments[$name]);
     }
@@ -171,7 +171,7 @@ class InputDefinition
      */
     public function getArgumentCount()
     {
-        return $this->hasAnArrayArgument ? PHP_INT_MAX : count($this->arguments);
+        return $this->hasAnArrayArgument ? PHP_INT_MAX : \count($this->arguments);
     }
 
     /**
@@ -378,7 +378,7 @@ class InputDefinition
             }
         }
 
-        if (count($elements) && $this->getArguments()) {
+        if (\count($elements) && $this->getArguments()) {
             $elements[] = '[--]';
         }
 
diff --git a/src/Symfony/Component/Console/Input/InputOption.php b/src/Symfony/Component/Console/Input/InputOption.php
index 184e369b86..a8dade4de7 100644
--- a/src/Symfony/Component/Console/Input/InputOption.php
+++ b/src/Symfony/Component/Console/Input/InputOption.php
@@ -56,7 +56,7 @@ class InputOption
         }
 
         if (null !== $shortcut) {
-            if (is_array($shortcut)) {
+            if (\is_array($shortcut)) {
                 $shortcut = implode('|', $shortcut);
             }
             $shortcuts = preg_split('{(\|)-?}', ltrim($shortcut, '-'));
@@ -162,7 +162,7 @@ class InputOption
         if ($this->isArray()) {
             if (null === $default) {
                 $default = array();
-            } elseif (!is_array($default)) {
+            } elseif (!\is_array($default)) {
                 throw new LogicException('A default value for an array option must be an array.');
             }
         }
diff --git a/src/Symfony/Component/Console/Input/StringInput.php b/src/Symfony/Component/Console/Input/StringInput.php
index d1394ececa..61e29481a4 100644
--- a/src/Symfony/Component/Console/Input/StringInput.php
+++ b/src/Symfony/Component/Console/Input/StringInput.php
@@ -49,14 +49,14 @@ class StringInput extends ArgvInput
     private function tokenize($input)
     {
         $tokens = array();
-        $length = strlen($input);
+        $length = \strlen($input);
         $cursor = 0;
         while ($cursor < $length) {
             if (preg_match('/\s+/A', $input, $match, null, $cursor)) {
             } elseif (preg_match('/([^="\'\s]+?)(=?)('.self::REGEX_QUOTED_STRING.'+)/A', $input, $match, null, $cursor)) {
-                $tokens[] = $match[1].$match[2].stripcslashes(str_replace(array('"\'', '\'"', '\'\'', '""'), '', substr($match[3], 1, strlen($match[3]) - 2)));
+                $tokens[] = $match[1].$match[2].stripcslashes(str_replace(array('"\'', '\'"', '\'\'', '""'), '', substr($match[3], 1, \strlen($match[3]) - 2)));
             } elseif (preg_match('/'.self::REGEX_QUOTED_STRING.'/A', $input, $match, null, $cursor)) {
-                $tokens[] = stripcslashes(substr($match[0], 1, strlen($match[0]) - 2));
+                $tokens[] = stripcslashes(substr($match[0], 1, \strlen($match[0]) - 2));
             } elseif (preg_match('/'.self::REGEX_STRING.'/A', $input, $match, null, $cursor)) {
                 $tokens[] = stripcslashes($match[1]);
             } else {
@@ -64,7 +64,7 @@ class StringInput extends ArgvInput
                 throw new InvalidArgumentException(sprintf('Unable to parse input near "... %s ..."', substr($input, $cursor, 10)));
             }
 
-            $cursor += strlen($match[0]);
+            $cursor += \strlen($match[0]);
         }
 
         return $tokens;
diff --git a/src/Symfony/Component/Console/Output/ConsoleOutput.php b/src/Symfony/Component/Console/Output/ConsoleOutput.php
index 87d93b88a5..e106d4f244 100644
--- a/src/Symfony/Component/Console/Output/ConsoleOutput.php
+++ b/src/Symfony/Component/Console/Output/ConsoleOutput.php
@@ -131,7 +131,7 @@ class ConsoleOutput extends StreamOutput implements ConsoleOutputInterface
     private function isRunningOS400()
     {
         $checks = array(
-            function_exists('php_uname') ? php_uname('s') : '',
+            \function_exists('php_uname') ? php_uname('s') : '',
             getenv('OSTYPE'),
             PHP_OS,
         );
diff --git a/src/Symfony/Component/Console/Output/StreamOutput.php b/src/Symfony/Component/Console/Output/StreamOutput.php
index d012a0a5c6..498d077283 100644
--- a/src/Symfony/Component/Console/Output/StreamOutput.php
+++ b/src/Symfony/Component/Console/Output/StreamOutput.php
@@ -42,7 +42,7 @@ class StreamOutput extends Output
      */
     public function __construct($stream, int $verbosity = self::VERBOSITY_NORMAL, bool $decorated = null, OutputFormatterInterface $formatter = null)
     {
-        if (!is_resource($stream) || 'stream' !== get_resource_type($stream)) {
+        if (!\is_resource($stream) || 'stream' !== get_resource_type($stream)) {
             throw new InvalidArgumentException('The StreamOutput class needs a stream as its first argument.');
         }
 
@@ -98,18 +98,18 @@ class StreamOutput extends Output
         }
 
         if (DIRECTORY_SEPARATOR === '\\') {
-            return (function_exists('sapi_windows_vt100_support')
+            return (\function_exists('sapi_windows_vt100_support')
                 && @sapi_windows_vt100_support($this->stream))
                 || false !== getenv('ANSICON')
                 || 'ON' === getenv('ConEmuANSI')
                 || 'xterm' === getenv('TERM');
         }
 
-        if (function_exists('stream_isatty')) {
+        if (\function_exists('stream_isatty')) {
             return @stream_isatty($this->stream);
         }
 
-        if (function_exists('posix_isatty')) {
+        if (\function_exists('posix_isatty')) {
             return @posix_isatty($this->stream);
         }
 
diff --git a/src/Symfony/Component/Console/Question/ChoiceQuestion.php b/src/Symfony/Component/Console/Question/ChoiceQuestion.php
index b66f2c685b..4aa6f67266 100644
--- a/src/Symfony/Component/Console/Question/ChoiceQuestion.php
+++ b/src/Symfony/Component/Console/Question/ChoiceQuestion.php
@@ -151,7 +151,7 @@ class ChoiceQuestion extends Question
                     }
                 }
 
-                if (count($results) > 1) {
+                if (\count($results) > 1) {
                     throw new InvalidArgumentException(sprintf('The provided answer is ambiguous. Value should be one of %s.', implode(' or ', $results)));
                 }
 
diff --git a/src/Symfony/Component/Console/Question/ConfirmationQuestion.php b/src/Symfony/Component/Console/Question/ConfirmationQuestion.php
index 7a15e5afb5..26eea6a136 100644
--- a/src/Symfony/Component/Console/Question/ConfirmationQuestion.php
+++ b/src/Symfony/Component/Console/Question/ConfirmationQuestion.php
@@ -44,7 +44,7 @@ class ConfirmationQuestion extends Question
         $regex = $this->trueAnswerRegex;
 
         return function ($answer) use ($default, $regex) {
-            if (is_bool($answer)) {
+            if (\is_bool($answer)) {
                 return $answer;
             }
 
diff --git a/src/Symfony/Component/Console/Question/Question.php b/src/Symfony/Component/Console/Question/Question.php
index 683998542c..4e05758b55 100644
--- a/src/Symfony/Component/Console/Question/Question.php
+++ b/src/Symfony/Component/Console/Question/Question.php
@@ -136,11 +136,11 @@ class Question
      */
     public function setAutocompleterValues($values)
     {
-        if (is_array($values)) {
+        if (\is_array($values)) {
             $values = $this->isAssoc($values) ? array_merge(array_keys($values), array_values($values)) : array_values($values);
         }
 
-        if (null !== $values && !is_array($values) && !$values instanceof \Traversable) {
+        if (null !== $values && !\is_array($values) && !$values instanceof \Traversable) {
             throw new InvalidArgumentException('Autocompleter values can be either an array, `null` or a `Traversable` object.');
         }
 
@@ -241,6 +241,6 @@ class Question
 
     protected function isAssoc($array)
     {
-        return (bool) count(array_filter(array_keys($array), 'is_string'));
+        return (bool) \count(array_filter(array_keys($array), 'is_string'));
     }
 }
diff --git a/src/Symfony/Component/Console/Style/SymfonyStyle.php b/src/Symfony/Component/Console/Style/SymfonyStyle.php
index 26018e2338..13ea2b066f 100644
--- a/src/Symfony/Component/Console/Style/SymfonyStyle.php
+++ b/src/Symfony/Component/Console/Style/SymfonyStyle.php
@@ -63,7 +63,7 @@ class SymfonyStyle extends OutputStyle
      */
     public function block($messages, $type = null, $style = null, $prefix = ' ', $padding = false, $escape = true)
     {
-        $messages = is_array($messages) ? array_values($messages) : array($messages);
+        $messages = \is_array($messages) ? array_values($messages) : array($messages);
 
         $this->autoPrependBlock();
         $this->writeln($this->createBlock($messages, $type, $style, $prefix, $padding, $escape));
@@ -117,7 +117,7 @@ class SymfonyStyle extends OutputStyle
     {
         $this->autoPrependText();
 
-        $messages = is_array($message) ? array_values($message) : array($message);
+        $messages = \is_array($message) ? array_values($message) : array($message);
         foreach ($messages as $message) {
             $this->writeln(sprintf(' %s', $message));
         }
@@ -396,7 +396,7 @@ class SymfonyStyle extends OutputStyle
 
         if (null !== $type) {
             $type = sprintf('[%s] ', $type);
-            $indentLength = strlen($type);
+            $indentLength = \strlen($type);
             $lineIndentation = str_repeat(' ', $indentLength);
         }
 
@@ -408,7 +408,7 @@ class SymfonyStyle extends OutputStyle
 
             $lines = array_merge($lines, explode(PHP_EOL, wordwrap($message, $this->lineLength - $prefixLength - $indentLength, PHP_EOL, true)));
 
-            if (count($messages) > 1 && $key < count($messages) - 1) {
+            if (\count($messages) > 1 && $key < \count($messages) - 1) {
                 $lines[] = '';
             }
         }
diff --git a/src/Symfony/Component/Console/Terminal.php b/src/Symfony/Component/Console/Terminal.php
index 927dfc4d76..af8807bed1 100644
--- a/src/Symfony/Component/Console/Terminal.php
+++ b/src/Symfony/Component/Console/Terminal.php
@@ -87,7 +87,7 @@ class Terminal
      */
     private static function getConsoleMode()
     {
-        if (!function_exists('proc_open')) {
+        if (!\function_exists('proc_open')) {
             return;
         }
 
@@ -96,7 +96,7 @@ class Terminal
             2 => array('pipe', 'w'),
         );
         $process = proc_open('mode CON', $descriptorspec, $pipes, null, null, array('suppress_errors' => true));
-        if (is_resource($process)) {
+        if (\is_resource($process)) {
             $info = stream_get_contents($pipes[1]);
             fclose($pipes[1]);
             fclose($pipes[2]);
@@ -115,7 +115,7 @@ class Terminal
      */
     private static function getSttyColumns()
     {
-        if (!function_exists('proc_open')) {
+        if (!\function_exists('proc_open')) {
             return;
         }
 
@@ -125,7 +125,7 @@ class Terminal
         );
 
         $process = proc_open('stty -a | grep columns', $descriptorspec, $pipes, null, null, array('suppress_errors' => true));
-        if (is_resource($process)) {
+        if (\is_resource($process)) {
             $info = stream_get_contents($pipes[1]);
             fclose($pipes[1]);
             fclose($pipes[2]);
diff --git a/src/Symfony/Component/Console/Tests/Command/CommandTest.php b/src/Symfony/Component/Console/Tests/Command/CommandTest.php
index 0e51632162..5ef98db46c 100644
--- a/src/Symfony/Component/Console/Tests/Command/CommandTest.php
+++ b/src/Symfony/Component/Console/Tests/Command/CommandTest.php
@@ -340,7 +340,7 @@ class CommandTest extends TestCase
         $command->setApplication(new Application());
         $command->setProcessTitle('foo');
         $this->assertSame(0, $command->run(new StringInput(''), new NullOutput()));
-        if (function_exists('cli_set_process_title')) {
+        if (\function_exists('cli_set_process_title')) {
             if (null === @cli_get_process_title() && 'Darwin' === PHP_OS) {
                 $this->markTestSkipped('Running "cli_get_process_title" as an unprivileged user is not supported on MacOS.');
             }
diff --git a/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php b/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php
index ea5268cae3..288de12cfb 100644
--- a/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php
+++ b/src/Symfony/Component/Console/Tests/Helper/QuestionHelperTest.php
@@ -276,7 +276,7 @@ class QuestionHelperTest extends AbstractQuestionHelperTest
 
         $error = 'This is not a color!';
         $validator = function ($color) use ($error) {
-            if (!in_array($color, array('white', 'black'))) {
+            if (!\in_array($color, array('white', 'black'))) {
                 throw new \InvalidArgumentException($error);
             }
 
diff --git a/src/Symfony/Component/CssSelector/Node/AbstractNode.php b/src/Symfony/Component/CssSelector/Node/AbstractNode.php
index 123ef1b117..aac3f0a555 100644
--- a/src/Symfony/Component/CssSelector/Node/AbstractNode.php
+++ b/src/Symfony/Component/CssSelector/Node/AbstractNode.php
@@ -34,7 +34,7 @@ abstract class AbstractNode implements NodeInterface
     public function getNodeName(): string
     {
         if (null === $this->nodeName) {
-            $this->nodeName = preg_replace('~.*\\\\([^\\\\]+)Node$~', '$1', get_called_class());
+            $this->nodeName = preg_replace('~.*\\\\([^\\\\]+)Node$~', '$1', \get_called_class());
         }
 
         return $this->nodeName;
diff --git a/src/Symfony/Component/CssSelector/Parser/Handler/HashHandler.php b/src/Symfony/Component/CssSelector/Parser/Handler/HashHandler.php
index f40807cdfb..9b3f6e2631 100644
--- a/src/Symfony/Component/CssSelector/Parser/Handler/HashHandler.php
+++ b/src/Symfony/Component/CssSelector/Parser/Handler/HashHandler.php
@@ -51,7 +51,7 @@ class HashHandler implements HandlerInterface
 
         $value = $this->escaping->escapeUnicode($match[1]);
         $stream->push(new Token(Token::TYPE_HASH, $value, $reader->getPosition()));
-        $reader->moveForward(strlen($match[0]));
+        $reader->moveForward(\strlen($match[0]));
 
         return true;
     }
diff --git a/src/Symfony/Component/CssSelector/Parser/Handler/IdentifierHandler.php b/src/Symfony/Component/CssSelector/Parser/Handler/IdentifierHandler.php
index 5ea0d5fd99..ecd083d7ab 100644
--- a/src/Symfony/Component/CssSelector/Parser/Handler/IdentifierHandler.php
+++ b/src/Symfony/Component/CssSelector/Parser/Handler/IdentifierHandler.php
@@ -51,7 +51,7 @@ class IdentifierHandler implements HandlerInterface
 
         $value = $this->escaping->escapeUnicode($match[0]);
         $stream->push(new Token(Token::TYPE_IDENTIFIER, $value, $reader->getPosition()));
-        $reader->moveForward(strlen($match[0]));
+        $reader->moveForward(\strlen($match[0]));
 
         return true;
     }
diff --git a/src/Symfony/Component/CssSelector/Parser/Handler/NumberHandler.php b/src/Symfony/Component/CssSelector/Parser/Handler/NumberHandler.php
index 41e5844ea8..e572bc5fec 100644
--- a/src/Symfony/Component/CssSelector/Parser/Handler/NumberHandler.php
+++ b/src/Symfony/Component/CssSelector/Parser/Handler/NumberHandler.php
@@ -47,7 +47,7 @@ class NumberHandler implements HandlerInterface
         }
 
         $stream->push(new Token(Token::TYPE_NUMBER, $match[0], $reader->getPosition()));
-        $reader->moveForward(strlen($match[0]));
+        $reader->moveForward(\strlen($match[0]));
 
         return true;
     }
diff --git a/src/Symfony/Component/CssSelector/Parser/Handler/StringHandler.php b/src/Symfony/Component/CssSelector/Parser/Handler/StringHandler.php
index fe92c1fcc7..909464445d 100644
--- a/src/Symfony/Component/CssSelector/Parser/Handler/StringHandler.php
+++ b/src/Symfony/Component/CssSelector/Parser/Handler/StringHandler.php
@@ -47,7 +47,7 @@ class StringHandler implements HandlerInterface
     {
         $quote = $reader->getSubstring(1);
 
-        if (!in_array($quote, array("'", '"'))) {
+        if (!\in_array($quote, array("'", '"'))) {
             return false;
         }
 
@@ -59,18 +59,18 @@ class StringHandler implements HandlerInterface
         }
 
         // check unclosed strings
-        if (strlen($match[0]) === $reader->getRemainingLength()) {
+        if (\strlen($match[0]) === $reader->getRemainingLength()) {
             throw SyntaxErrorException::unclosedString($reader->getPosition() - 1);
         }
 
         // check quotes pairs validity
-        if ($quote !== $reader->getSubstring(1, strlen($match[0]))) {
+        if ($quote !== $reader->getSubstring(1, \strlen($match[0]))) {
             throw SyntaxErrorException::unclosedString($reader->getPosition() - 1);
         }
 
         $string = $this->escaping->escapeUnicodeAndNewLine($match[0]);
         $stream->push(new Token(Token::TYPE_STRING, $string, $reader->getPosition()));
-        $reader->moveForward(strlen($match[0]) + 1);
+        $reader->moveForward(\strlen($match[0]) + 1);
 
         return true;
     }
diff --git a/src/Symfony/Component/CssSelector/Parser/Handler/WhitespaceHandler.php b/src/Symfony/Component/CssSelector/Parser/Handler/WhitespaceHandler.php
index ebf8a19fe2..21345e32c7 100644
--- a/src/Symfony/Component/CssSelector/Parser/Handler/WhitespaceHandler.php
+++ b/src/Symfony/Component/CssSelector/Parser/Handler/WhitespaceHandler.php
@@ -39,7 +39,7 @@ class WhitespaceHandler implements HandlerInterface
         }
 
         $stream->push(new Token(Token::TYPE_WHITESPACE, $match[0], $reader->getPosition()));
-        $reader->moveForward(strlen($match[0]));
+        $reader->moveForward(\strlen($match[0]));
 
         return true;
     }
diff --git a/src/Symfony/Component/CssSelector/Parser/Parser.php b/src/Symfony/Component/CssSelector/Parser/Parser.php
index dc84cc1826..d42bdca604 100644
--- a/src/Symfony/Component/CssSelector/Parser/Parser.php
+++ b/src/Symfony/Component/CssSelector/Parser/Parser.php
@@ -150,7 +150,7 @@ class Parser implements ParserInterface
     {
         $stream->skipWhitespace();
 
-        $selectorStart = count($stream->getUsed());
+        $selectorStart = \count($stream->getUsed());
         $result = $this->parseElementNode($stream);
         $pseudoElement = null;
 
@@ -187,7 +187,7 @@ class Parser implements ParserInterface
                 }
 
                 $identifier = $stream->getNextIdentifier();
-                if (in_array(strtolower($identifier), array('first-line', 'first-letter', 'before', 'after'))) {
+                if (\in_array(strtolower($identifier), array('first-line', 'first-letter', 'before', 'after'))) {
                     // Special case: CSS 2.1 pseudo-elements can have a single ':'.
                     // Any new pseudo-element must have two.
                     $pseudoElement = $identifier;
@@ -253,7 +253,7 @@ class Parser implements ParserInterface
             }
         }
 
-        if (count($stream->getUsed()) === $selectorStart) {
+        if (\count($stream->getUsed()) === $selectorStart) {
             throw SyntaxErrorException::unexpectedToken('selector', $stream->getPeek());
         }
 
diff --git a/src/Symfony/Component/CssSelector/Parser/Reader.php b/src/Symfony/Component/CssSelector/Parser/Reader.php
index adfd3c2113..4b43effed3 100644
--- a/src/Symfony/Component/CssSelector/Parser/Reader.php
+++ b/src/Symfony/Component/CssSelector/Parser/Reader.php
@@ -30,7 +30,7 @@ class Reader
     public function __construct(string $source)
     {
         $this->source = $source;
-        $this->length = strlen($source);
+        $this->length = \strlen($source);
     }
 
     public function isEOF(): bool
diff --git a/src/Symfony/Component/CssSelector/Parser/Token.php b/src/Symfony/Component/CssSelector/Parser/Token.php
index 554deb8e4a..91a98f7154 100644
--- a/src/Symfony/Component/CssSelector/Parser/Token.php
+++ b/src/Symfony/Component/CssSelector/Parser/Token.php
@@ -72,7 +72,7 @@ class Token
             return true;
         }
 
-        return in_array($this->value, $values);
+        return \in_array($this->value, $values);
     }
 
     public function isWhitespace(): bool
diff --git a/src/Symfony/Component/CssSelector/Parser/Tokenizer/TokenizerEscaping.php b/src/Symfony/Component/CssSelector/Parser/Tokenizer/TokenizerEscaping.php
index 2df63f5162..200272f23d 100644
--- a/src/Symfony/Component/CssSelector/Parser/Tokenizer/TokenizerEscaping.php
+++ b/src/Symfony/Component/CssSelector/Parser/Tokenizer/TokenizerEscaping.php
@@ -50,13 +50,13 @@ class TokenizerEscaping
             $c = hexdec($match[1]);
 
             if (0x80 > $c %= 0x200000) {
-                return chr($c);
+                return \chr($c);
             }
             if (0x800 > $c) {
-                return chr(0xC0 | $c >> 6).chr(0x80 | $c & 0x3F);
+                return \chr(0xC0 | $c >> 6).\chr(0x80 | $c & 0x3F);
             }
             if (0x10000 > $c) {
-                return chr(0xE0 | $c >> 12).chr(0x80 | $c >> 6 & 0x3F).chr(0x80 | $c & 0x3F);
+                return \chr(0xE0 | $c >> 12).\chr(0x80 | $c >> 6 & 0x3F).\chr(0x80 | $c & 0x3F);
             }
         }, $value);
     }
diff --git a/src/Symfony/Component/CssSelector/Tests/Parser/Handler/AbstractHandlerTest.php b/src/Symfony/Component/CssSelector/Tests/Parser/Handler/AbstractHandlerTest.php
index 8005616a92..f5c9dc8bfe 100644
--- a/src/Symfony/Component/CssSelector/Tests/Parser/Handler/AbstractHandlerTest.php
+++ b/src/Symfony/Component/CssSelector/Tests/Parser/Handler/AbstractHandlerTest.php
@@ -63,7 +63,7 @@ abstract class AbstractHandlerTest extends TestCase
             $this->assertEquals(0, $reader->getRemainingLength());
             $this->assertTrue($reader->isEOF());
         } else {
-            $this->assertEquals(strlen($remainingContent), $reader->getRemainingLength());
+            $this->assertEquals(\strlen($remainingContent), $reader->getRemainingLength());
             $this->assertEquals(0, $reader->getOffset($remainingContent));
         }
     }
diff --git a/src/Symfony/Component/CssSelector/Tests/XPath/TranslatorTest.php b/src/Symfony/Component/CssSelector/Tests/XPath/TranslatorTest.php
index 519417835c..610458297e 100644
--- a/src/Symfony/Component/CssSelector/Tests/XPath/TranslatorTest.php
+++ b/src/Symfony/Component/CssSelector/Tests/XPath/TranslatorTest.php
@@ -37,9 +37,9 @@ class TranslatorTest extends TestCase
         $translator = new Translator();
         $document = new \SimpleXMLElement(file_get_contents(__DIR__.'/Fixtures/lang.xml'));
         $elements = $document->xpath($translator->cssToXPath($css));
-        $this->assertCount(count($elementsId), $elements);
+        $this->assertCount(\count($elementsId), $elements);
         foreach ($elements as $element) {
-            $this->assertTrue(in_array($element->attributes()->id, $elementsId));
+            $this->assertTrue(\in_array($element->attributes()->id, $elementsId));
         }
     }
 
@@ -54,10 +54,10 @@ class TranslatorTest extends TestCase
         $document->loadHTMLFile(__DIR__.'/Fixtures/ids.html');
         $document = simplexml_import_dom($document);
         $elements = $document->xpath($translator->cssToXPath($css));
-        $this->assertCount(count($elementsId), $elementsId);
+        $this->assertCount(\count($elementsId), $elementsId);
         foreach ($elements as $element) {
             if (null !== $element->attributes()->id) {
-                $this->assertTrue(in_array($element->attributes()->id, $elementsId));
+                $this->assertTrue(\in_array($element->attributes()->id, $elementsId));
             }
         }
         libxml_clear_errors();
diff --git a/src/Symfony/Component/CssSelector/XPath/Extension/AttributeMatchingExtension.php b/src/Symfony/Component/CssSelector/XPath/Extension/AttributeMatchingExtension.php
index ee8976fdd0..8a4d884212 100644
--- a/src/Symfony/Component/CssSelector/XPath/Extension/AttributeMatchingExtension.php
+++ b/src/Symfony/Component/CssSelector/XPath/Extension/AttributeMatchingExtension.php
@@ -86,7 +86,7 @@ class AttributeMatchingExtension extends AbstractExtension
         return $xpath->addCondition($value ? sprintf(
             '%1$s and substring(%1$s, string-length(%1$s)-%2$s) = %3$s',
             $attribute,
-            strlen($value) - 1,
+            \strlen($value) - 1,
             Translator::getXpathLiteral($value)
         ) : '0');
     }
diff --git a/src/Symfony/Component/CssSelector/XPath/Translator.php b/src/Symfony/Component/CssSelector/XPath/Translator.php
index 73b548215d..2b44e5fb8a 100644
--- a/src/Symfony/Component/CssSelector/XPath/Translator.php
+++ b/src/Symfony/Component/CssSelector/XPath/Translator.php
@@ -155,7 +155,7 @@ class Translator implements TranslatorInterface
             throw new ExpressionErrorException(sprintf('Node "%s" not supported.', $node->getNodeName()));
         }
 
-        return call_user_func($this->nodeTranslators[$node->getNodeName()], $node, $this);
+        return \call_user_func($this->nodeTranslators[$node->getNodeName()], $node, $this);
     }
 
     /**
@@ -167,7 +167,7 @@ class Translator implements TranslatorInterface
             throw new ExpressionErrorException(sprintf('Combiner "%s" not supported.', $combiner));
         }
 
-        return call_user_func($this->combinationTranslators[$combiner], $this->nodeToXPath($xpath), $this->nodeToXPath($combinedXpath));
+        return \call_user_func($this->combinationTranslators[$combiner], $this->nodeToXPath($xpath), $this->nodeToXPath($combinedXpath));
     }
 
     /**
@@ -179,7 +179,7 @@ class Translator implements TranslatorInterface
             throw new ExpressionErrorException(sprintf('Function "%s" not supported.', $function->getName()));
         }
 
-        return call_user_func($this->functionTranslators[$function->getName()], $xpath, $function);
+        return \call_user_func($this->functionTranslators[$function->getName()], $xpath, $function);
     }
 
     /**
@@ -191,7 +191,7 @@ class Translator implements TranslatorInterface
             throw new ExpressionErrorException(sprintf('Pseudo-class "%s" not supported.', $pseudoClass));
         }
 
-        return call_user_func($this->pseudoClassTranslators[$pseudoClass], $xpath);
+        return \call_user_func($this->pseudoClassTranslators[$pseudoClass], $xpath);
     }
 
     /**
@@ -203,7 +203,7 @@ class Translator implements TranslatorInterface
             throw new ExpressionErrorException(sprintf('Attribute matcher operator "%s" not supported.', $operator));
         }
 
-        return call_user_func($this->attributeMatchingTranslators[$operator], $xpath, $attribute, $value);
+        return \call_user_func($this->attributeMatchingTranslators[$operator], $xpath, $attribute, $value);
     }
 
     /**
diff --git a/src/Symfony/Component/Debug/DebugClassLoader.php b/src/Symfony/Component/Debug/DebugClassLoader.php
index f9c80d041b..07d490b4f5 100644
--- a/src/Symfony/Component/Debug/DebugClassLoader.php
+++ b/src/Symfony/Component/Debug/DebugClassLoader.php
@@ -39,7 +39,7 @@ class DebugClassLoader
     public function __construct(callable $classLoader)
     {
         $this->classLoader = $classLoader;
-        $this->isFinder = is_array($classLoader) && method_exists($classLoader[0], 'findFile');
+        $this->isFinder = \is_array($classLoader) && method_exists($classLoader[0], 'findFile');
 
         if (!isset(self::$caseCheck)) {
             $file = file_exists(__FILE__) ? __FILE__ : rtrim(realpath('.'), DIRECTORY_SEPARATOR);
@@ -52,7 +52,7 @@ class DebugClassLoader
             if (false === $test || false === $i) {
                 // filesystem is case sensitive
                 self::$caseCheck = 0;
-            } elseif (substr($test, -strlen($file)) === $file) {
+            } elseif (substr($test, -\strlen($file)) === $file) {
                 // filesystem is case insensitive and realpath() normalizes the case of characters
                 self::$caseCheck = 1;
             } elseif (false !== stripos(PHP_OS, 'darwin')) {
@@ -84,7 +84,7 @@ class DebugClassLoader
         class_exists('Symfony\Component\Debug\ErrorHandler');
         class_exists('Psr\Log\LogLevel');
 
-        if (!is_array($functions = spl_autoload_functions())) {
+        if (!\is_array($functions = spl_autoload_functions())) {
             return;
         }
 
@@ -93,7 +93,7 @@ class DebugClassLoader
         }
 
         foreach ($functions as $function) {
-            if (!is_array($function) || !$function[0] instanceof self) {
+            if (!\is_array($function) || !$function[0] instanceof self) {
                 $function = array(new static($function), 'loadClass');
             }
 
@@ -106,7 +106,7 @@ class DebugClassLoader
      */
     public static function disable()
     {
-        if (!is_array($functions = spl_autoload_functions())) {
+        if (!\is_array($functions = spl_autoload_functions())) {
             return;
         }
 
@@ -115,7 +115,7 @@ class DebugClassLoader
         }
 
         foreach ($functions as $function) {
-            if (is_array($function) && $function[0] instanceof self) {
+            if (\is_array($function) && $function[0] instanceof self) {
                 $function = $function[0]->getClassLoader();
             }
 
@@ -149,7 +149,7 @@ class DebugClassLoader
                     }
                 }
             } else {
-                call_user_func($this->classLoader, $class);
+                \call_user_func($this->classLoader, $class);
                 $file = false;
             }
         } finally {
@@ -291,8 +291,8 @@ class DebugClassLoader
                 $real = explode('\\', $class.strrchr($file, '.'));
                 $tail = explode(DIRECTORY_SEPARATOR, str_replace('/', DIRECTORY_SEPARATOR, $file));
 
-                $i = count($tail) - 1;
-                $j = count($real) - 1;
+                $i = \count($tail) - 1;
+                $j = \count($real) - 1;
 
                 while (isset($tail[$i], $real[$j]) && $tail[$i] === $real[$j]) {
                     --$i;
@@ -303,7 +303,7 @@ class DebugClassLoader
             }
             if (self::$caseCheck && $tail) {
                 $tail = DIRECTORY_SEPARATOR.implode(DIRECTORY_SEPARATOR, $tail);
-                $tailLen = strlen($tail);
+                $tailLen = \strlen($tail);
                 $real = $refl->getFileName();
 
                 if (2 === self::$caseCheck) {
@@ -328,7 +328,7 @@ class DebugClassLoader
 
                             $dir = $real;
                             $k = $kDir;
-                            $i = strlen($dir) - 1;
+                            $i = \strlen($dir) - 1;
                             while (!isset(self::$darwinCache[$k])) {
                                 self::$darwinCache[$k] = array($dir, array());
                                 self::$darwinCache[$dir] = &self::$darwinCache[$k];
diff --git a/src/Symfony/Component/Debug/ErrorHandler.php b/src/Symfony/Component/Debug/ErrorHandler.php
index 2702b4157f..3480ca7183 100644
--- a/src/Symfony/Component/Debug/ErrorHandler.php
+++ b/src/Symfony/Component/Debug/ErrorHandler.php
@@ -127,17 +127,17 @@ class ErrorHandler
             $handler->isRoot = true;
         }
 
-        if ($handlerIsNew && is_array($prev) && $prev[0] instanceof self) {
+        if ($handlerIsNew && \is_array($prev) && $prev[0] instanceof self) {
             $handler = $prev[0];
             $replace = false;
         }
         if (!$replace && $prev) {
             restore_error_handler();
-            $handlerIsRegistered = is_array($prev) && $handler === $prev[0];
+            $handlerIsRegistered = \is_array($prev) && $handler === $prev[0];
         } else {
             $handlerIsRegistered = true;
         }
-        if (is_array($prev = set_exception_handler(array($handler, 'handleException'))) && $prev[0] instanceof self) {
+        if (\is_array($prev = set_exception_handler(array($handler, 'handleException'))) && $prev[0] instanceof self) {
             restore_exception_handler();
             if (!$handlerIsRegistered) {
                 $handler = $prev[0];
@@ -177,7 +177,7 @@ class ErrorHandler
     {
         $loggers = array();
 
-        if (is_array($levels)) {
+        if (\is_array($levels)) {
             foreach ($levels as $type => $logLevel) {
                 if (empty($this->loggers[$type][0]) || $replace || $this->loggers[$type][0] === $this->bootstrappingLogger) {
                     $loggers[$type] = array($logger, $logLevel);
@@ -217,7 +217,7 @@ class ErrorHandler
             if (!isset($prev[$type])) {
                 throw new \InvalidArgumentException('Unknown error type: '.$type);
             }
-            if (!is_array($log)) {
+            if (!\is_array($log)) {
                 $log = array($log);
             } elseif (!array_key_exists(0, $log)) {
                 throw new \InvalidArgumentException('No logger provided');
@@ -350,7 +350,7 @@ class ErrorHandler
     {
         if ($prev !== $this->thrownErrors | $this->loggedErrors) {
             $handler = set_error_handler('var_dump');
-            $handler = is_array($handler) ? $handler[0] : null;
+            $handler = \is_array($handler) ? $handler[0] : null;
             restore_error_handler();
             if ($handler === $this) {
                 restore_error_handler();
@@ -393,7 +393,7 @@ class ErrorHandler
         }
         $scope = $this->scopedErrors & $type;
 
-        if (4 < $numArgs = func_num_args()) {
+        if (4 < $numArgs = \func_num_args()) {
             $context = $scope ? (func_get_arg(4) ?: array()) : array();
         } else {
             $context = array();
@@ -583,7 +583,7 @@ class ErrorHandler
         $previousHandler = null;
         $sameHandlerLimit = 10;
 
-        while (!is_array($handler) || !$handler[0] instanceof self) {
+        while (!\is_array($handler) || !$handler[0] instanceof self) {
             $handler = set_exception_handler('var_dump');
             restore_exception_handler();
 
@@ -667,7 +667,7 @@ class ErrorHandler
 
         for ($i = 0; isset($backtrace[$i]); ++$i) {
             if (isset($backtrace[$i]['file'], $backtrace[$i]['line']) && $backtrace[$i]['line'] === $line && $backtrace[$i]['file'] === $file) {
-                $lightTrace = array_slice($lightTrace, 1 + $i);
+                $lightTrace = \array_slice($lightTrace, 1 + $i);
                 break;
             }
         }
diff --git a/src/Symfony/Component/Debug/Exception/FatalErrorException.php b/src/Symfony/Component/Debug/Exception/FatalErrorException.php
index c6c52a93d5..8305d39218 100644
--- a/src/Symfony/Component/Debug/Exception/FatalErrorException.php
+++ b/src/Symfony/Component/Debug/Exception/FatalErrorException.php
@@ -31,7 +31,7 @@ class FatalErrorException extends \ErrorException
 
             $this->setTrace($trace);
         } elseif (null !== $traceOffset) {
-            if (function_exists('xdebug_get_function_stack')) {
+            if (\function_exists('xdebug_get_function_stack')) {
                 $trace = xdebug_get_function_stack();
                 if (0 < $traceOffset) {
                     array_splice($trace, -$traceOffset);
diff --git a/src/Symfony/Component/Debug/Exception/FlattenException.php b/src/Symfony/Component/Debug/Exception/FlattenException.php
index 2afffa21b6..b091b55bd4 100644
--- a/src/Symfony/Component/Debug/Exception/FlattenException.php
+++ b/src/Symfony/Component/Debug/Exception/FlattenException.php
@@ -241,9 +241,9 @@ class FlattenException
             if ($value instanceof \__PHP_Incomplete_Class) {
                 // is_object() returns false on PHP<=7.1
                 $result[$key] = array('incomplete-object', $this->getClassNameFromIncomplete($value));
-            } elseif (is_object($value)) {
-                $result[$key] = array('object', get_class($value));
-            } elseif (is_array($value)) {
+            } elseif (\is_object($value)) {
+                $result[$key] = array('object', \get_class($value));
+            } elseif (\is_array($value)) {
                 if ($level > 10) {
                     $result[$key] = array('array', '*DEEP NESTED ARRAY*');
                 } else {
@@ -251,13 +251,13 @@ class FlattenException
                 }
             } elseif (null === $value) {
                 $result[$key] = array('null', null);
-            } elseif (is_bool($value)) {
+            } elseif (\is_bool($value)) {
                 $result[$key] = array('boolean', $value);
-            } elseif (is_int($value)) {
+            } elseif (\is_int($value)) {
                 $result[$key] = array('integer', $value);
-            } elseif (is_float($value)) {
+            } elseif (\is_float($value)) {
                 $result[$key] = array('float', $value);
-            } elseif (is_resource($value)) {
+            } elseif (\is_resource($value)) {
                 $result[$key] = array('resource', get_resource_type($value));
             } else {
                 $result[$key] = array('string', (string) $value);
diff --git a/src/Symfony/Component/Debug/ExceptionHandler.php b/src/Symfony/Component/Debug/ExceptionHandler.php
index 0e3ec00717..1845bc88c3 100644
--- a/src/Symfony/Component/Debug/ExceptionHandler.php
+++ b/src/Symfony/Component/Debug/ExceptionHandler.php
@@ -57,7 +57,7 @@ class ExceptionHandler
         $handler = new static($debug, $charset, $fileLinkFormat);
 
         $prev = set_exception_handler(array($handler, 'handle'));
-        if (is_array($prev) && $prev[0] instanceof ErrorHandler) {
+        if (\is_array($prev) && $prev[0] instanceof ErrorHandler) {
             restore_exception_handler();
             $prev[0]->setExceptionHandler(array($handler, 'handle'));
         }
@@ -142,7 +142,7 @@ class ExceptionHandler
         $this->caughtBuffer = null;
 
         try {
-            call_user_func($this->handler, $exception);
+            \call_user_func($this->handler, $exception);
             $this->caughtLength = $caughtLength;
         } catch (\Exception $e) {
             if (!$caughtLength) {
@@ -218,7 +218,7 @@ EOF;
 
         $content = '';
         try {
-            $count = count($exception->getAllPrevious());
+            $count = \count($exception->getAllPrevious());
             $total = $count + 1;
             foreach ($exception->toArray() as $position => $e) {
                 $ind = $count - $position + 1;
@@ -253,7 +253,7 @@ EOF
         } catch (\Exception $e) {
             // something nasty happened and we cannot throw an exception anymore
             if ($this->debug) {
-                $title = sprintf('Exception thrown when handling an exception (%s: %s)', get_class($e), $this->escapeHtml($e->getMessage()));
+                $title = sprintf('Exception thrown when handling an exception (%s: %s)', \get_class($e), $this->escapeHtml($e->getMessage()));
             } else {
                 $title = 'Whoops, looks like something went wrong.';
             }
@@ -376,12 +376,12 @@ EOF;
         }
 
         if (\is_string($fmt)) {
-            $i = strpos($f = $fmt, '&', max(strrpos($f, '%f'), strrpos($f, '%l'))) ?: strlen($f);
+            $i = strpos($f = $fmt, '&', max(strrpos($f, '%f'), strrpos($f, '%l'))) ?: \strlen($f);
             $fmt = array(substr($f, 0, $i)) + preg_split('/&([^>]++)>/', substr($f, $i), -1, PREG_SPLIT_DELIM_CAPTURE);
 
             for ($i = 1; isset($fmt[$i]); ++$i) {
                 if (0 === strpos($path, $k = $fmt[$i++])) {
-                    $path = substr_replace($path, $fmt[$i], 0, strlen($k));
+                    $path = substr_replace($path, $fmt[$i], 0, \strlen($k));
                     break;
                 }
             }
@@ -408,7 +408,7 @@ EOF;
             if ('object' === $item[0]) {
                 $formattedValue = sprintf('<em>object</em>(%s)', $this->formatClass($item[1]));
             } elseif ('array' === $item[0]) {
-                $formattedValue = sprintf('<em>array</em>(%s)', is_array($item[1]) ? $this->formatArgs($item[1]) : $item[1]);
+                $formattedValue = sprintf('<em>array</em>(%s)', \is_array($item[1]) ? $this->formatArgs($item[1]) : $item[1]);
             } elseif ('null' === $item[0]) {
                 $formattedValue = '<em>null</em>';
             } elseif ('boolean' === $item[0]) {
@@ -419,7 +419,7 @@ EOF;
                 $formattedValue = str_replace("\n", '', $this->escapeHtml(var_export($item[1], true)));
             }
 
-            $result[] = is_int($key) ? $formattedValue : sprintf("'%s' => %s", $this->escapeHtml($key), $formattedValue);
+            $result[] = \is_int($key) ? $formattedValue : sprintf("'%s' => %s", $this->escapeHtml($key), $formattedValue);
         }
 
         return implode(', ', $result);
diff --git a/src/Symfony/Component/Debug/FatalErrorHandler/ClassNotFoundFatalErrorHandler.php b/src/Symfony/Component/Debug/FatalErrorHandler/ClassNotFoundFatalErrorHandler.php
index 25030e5606..4391d5ad0b 100644
--- a/src/Symfony/Component/Debug/FatalErrorHandler/ClassNotFoundFatalErrorHandler.php
+++ b/src/Symfony/Component/Debug/FatalErrorHandler/ClassNotFoundFatalErrorHandler.php
@@ -29,9 +29,9 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
      */
     public function handleError(array $error, FatalErrorException $exception)
     {
-        $messageLen = strlen($error['message']);
+        $messageLen = \strlen($error['message']);
         $notFoundSuffix = '\' not found';
-        $notFoundSuffixLen = strlen($notFoundSuffix);
+        $notFoundSuffixLen = \strlen($notFoundSuffix);
         if ($notFoundSuffixLen > $messageLen) {
             return;
         }
@@ -42,7 +42,7 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
 
         foreach (array('class', 'interface', 'trait') as $typeName) {
             $prefix = ucfirst($typeName).' \'';
-            $prefixLen = strlen($prefix);
+            $prefixLen = \strlen($prefix);
             if (0 !== strpos($error['message'], $prefix)) {
                 continue;
             }
@@ -85,7 +85,7 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
      */
     private function getClassCandidates(string $class): array
     {
-        if (!is_array($functions = spl_autoload_functions())) {
+        if (!\is_array($functions = spl_autoload_functions())) {
             return array();
         }
 
@@ -93,14 +93,14 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
         $classes = array();
 
         foreach ($functions as $function) {
-            if (!is_array($function)) {
+            if (!\is_array($function)) {
                 continue;
             }
             // get class loaders wrapped by DebugClassLoader
             if ($function[0] instanceof DebugClassLoader) {
                 $function = $function[0]->getClassLoader();
 
-                if (!is_array($function)) {
+                if (!\is_array($function)) {
                     continue;
                 }
             }
@@ -126,7 +126,7 @@ class ClassNotFoundFatalErrorHandler implements FatalErrorHandlerInterface
 
     private function findClassInPath(string $path, string $class, string $prefix): array
     {
-        if (!$path = realpath($path.'/'.strtr($prefix, '\\_', '//')) ?: realpath($path.'/'.dirname(strtr($prefix, '\\_', '//'))) ?: realpath($path)) {
+        if (!$path = realpath($path.'/'.strtr($prefix, '\\_', '//')) ?: realpath($path.'/'.\dirname(strtr($prefix, '\\_', '//'))) ?: realpath($path)) {
             return array();
         }
 
diff --git a/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php b/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php
index c6f391a79c..6bfe5f97f4 100644
--- a/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php
+++ b/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedFunctionFatalErrorHandler.php
@@ -26,9 +26,9 @@ class UndefinedFunctionFatalErrorHandler implements FatalErrorHandlerInterface
      */
     public function handleError(array $error, FatalErrorException $exception)
     {
-        $messageLen = strlen($error['message']);
+        $messageLen = \strlen($error['message']);
         $notFoundSuffix = '()';
-        $notFoundSuffixLen = strlen($notFoundSuffix);
+        $notFoundSuffixLen = \strlen($notFoundSuffix);
         if ($notFoundSuffixLen > $messageLen) {
             return;
         }
@@ -38,7 +38,7 @@ class UndefinedFunctionFatalErrorHandler implements FatalErrorHandlerInterface
         }
 
         $prefix = 'Call to undefined function ';
-        $prefixLen = strlen($prefix);
+        $prefixLen = \strlen($prefix);
         if (0 !== strpos($error['message'], $prefix)) {
             return;
         }
diff --git a/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedMethodFatalErrorHandler.php b/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedMethodFatalErrorHandler.php
index 6fa62b6f24..618a2c208b 100644
--- a/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedMethodFatalErrorHandler.php
+++ b/src/Symfony/Component/Debug/FatalErrorHandler/UndefinedMethodFatalErrorHandler.php
@@ -44,7 +44,7 @@ class UndefinedMethodFatalErrorHandler implements FatalErrorHandlerInterface
         $candidates = array();
         foreach ($methods as $definedMethodName) {
             $lev = levenshtein($methodName, $definedMethodName);
-            if ($lev <= strlen($methodName) / 3 || false !== strpos($definedMethodName, $methodName)) {
+            if ($lev <= \strlen($methodName) / 3 || false !== strpos($definedMethodName, $methodName)) {
                 $candidates[] = $definedMethodName;
             }
         }
diff --git a/src/Symfony/Component/Debug/Tests/ErrorHandlerTest.php b/src/Symfony/Component/Debug/Tests/ErrorHandlerTest.php
index eee8e9dc57..15e476381a 100644
--- a/src/Symfony/Component/Debug/Tests/ErrorHandlerTest.php
+++ b/src/Symfony/Component/Debug/Tests/ErrorHandlerTest.php
@@ -480,7 +480,7 @@ class ErrorHandlerTest extends TestCase
 
         $handler = new ErrorHandler();
         $handler->setExceptionHandler(function () use (&$args) {
-            $args = func_get_args();
+            $args = \func_get_args();
         });
 
         $handler->handleException($exception);
diff --git a/src/Symfony/Component/Debug/Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php b/src/Symfony/Component/Debug/Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php
index 65c80fc1cf..8ffe7f8500 100644
--- a/src/Symfony/Component/Debug/Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php
+++ b/src/Symfony/Component/Debug/Tests/FatalErrorHandler/ClassNotFoundFatalErrorHandlerTest.php
@@ -22,7 +22,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
     public static function setUpBeforeClass()
     {
         foreach (spl_autoload_functions() as $function) {
-            if (!is_array($function)) {
+            if (!\is_array($function)) {
                 continue;
             }
 
@@ -32,7 +32,7 @@ class ClassNotFoundFatalErrorHandlerTest extends TestCase
             }
 
             if ($function[0] instanceof ComposerClassLoader) {
-                $function[0]->add('Symfony_Component_Debug_Tests_Fixtures', dirname(dirname(dirname(dirname(dirname(__DIR__))))));
+                $function[0]->add('Symfony_Component_Debug_Tests_Fixtures', \dirname(\dirname(\dirname(\dirname(\dirname(__DIR__))))));
                 break;
             }
         }
diff --git a/src/Symfony/Component/Debug/Tests/HeaderMock.php b/src/Symfony/Component/Debug/Tests/HeaderMock.php
index 65d0b58855..3d8d84c5a4 100644
--- a/src/Symfony/Component/Debug/Tests/HeaderMock.php
+++ b/src/Symfony/Component/Debug/Tests/HeaderMock.php
@@ -27,12 +27,12 @@ function testHeader()
 {
     static $headers = array();
 
-    if (!$h = func_get_args()) {
+    if (!$h = \func_get_args()) {
         $h = $headers;
         $headers = array();
 
         return $h;
     }
 
-    $headers[] = func_get_args();
+    $headers[] = \func_get_args();
 }
diff --git a/src/Symfony/Component/Debug/Tests/phpt/debug_class_loader.phpt b/src/Symfony/Component/Debug/Tests/phpt/debug_class_loader.phpt
index 685280bc8a..41c56c9309 100644
--- a/src/Symfony/Component/Debug/Tests/phpt/debug_class_loader.phpt
+++ b/src/Symfony/Component/Debug/Tests/phpt/debug_class_loader.phpt
@@ -9,7 +9,7 @@ use Symfony\Component\Debug\DebugClassLoader;
 
 $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
-    $vendor = dirname($vendor);
+    $vendor = \dirname($vendor);
 }
 require $vendor.'/vendor/autoload.php';
 
diff --git a/src/Symfony/Component/Debug/Tests/phpt/decorate_exception_hander.phpt b/src/Symfony/Component/Debug/Tests/phpt/decorate_exception_hander.phpt
index 7ce7b9dc6f..74cf2e9171 100644
--- a/src/Symfony/Component/Debug/Tests/phpt/decorate_exception_hander.phpt
+++ b/src/Symfony/Component/Debug/Tests/phpt/decorate_exception_hander.phpt
@@ -7,7 +7,7 @@ namespace Symfony\Component\Debug;
 
 $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
-    $vendor = dirname($vendor);
+    $vendor = \dirname($vendor);
 }
 require $vendor.'/vendor/autoload.php';
 
diff --git a/src/Symfony/Component/Debug/Tests/phpt/exception_rethrown.phpt b/src/Symfony/Component/Debug/Tests/phpt/exception_rethrown.phpt
index 9df0a65cf7..3f45595430 100644
--- a/src/Symfony/Component/Debug/Tests/phpt/exception_rethrown.phpt
+++ b/src/Symfony/Component/Debug/Tests/phpt/exception_rethrown.phpt
@@ -7,7 +7,7 @@ namespace Symfony\Component\Debug;
 
 $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
-    $vendor = dirname($vendor);
+    $vendor = \dirname($vendor);
 }
 require $vendor.'/vendor/autoload.php';
 
diff --git a/src/Symfony/Component/Debug/Tests/phpt/fatal_with_nested_handlers.phpt b/src/Symfony/Component/Debug/Tests/phpt/fatal_with_nested_handlers.phpt
index 5c5245c069..2b74e5c685 100644
--- a/src/Symfony/Component/Debug/Tests/phpt/fatal_with_nested_handlers.phpt
+++ b/src/Symfony/Component/Debug/Tests/phpt/fatal_with_nested_handlers.phpt
@@ -7,7 +7,7 @@ namespace Symfony\Component\Debug;
 
 $vendor = __DIR__;
 while (!file_exists($vendor.'/vendor')) {
-    $vendor = dirname($vendor);
+    $vendor = \dirname($vendor);
 }
 require $vendor.'/vendor/autoload.php';
 
diff --git a/src/Symfony/Component/DependencyInjection/Alias.php b/src/Symfony/Component/DependencyInjection/Alias.php
index 55e385f674..24484de167 100644
--- a/src/Symfony/Component/DependencyInjection/Alias.php
+++ b/src/Symfony/Component/DependencyInjection/Alias.php
@@ -21,7 +21,7 @@ class Alias
     {
         $this->id = $id;
         $this->public = $public;
-        $this->private = 2 > func_num_args();
+        $this->private = 2 > \func_num_args();
     }
 
     /**
diff --git a/src/Symfony/Component/DependencyInjection/Argument/ReferenceSetArgumentTrait.php b/src/Symfony/Component/DependencyInjection/Argument/ReferenceSetArgumentTrait.php
index 94ed23971b..6f8d5d97e5 100644
--- a/src/Symfony/Component/DependencyInjection/Argument/ReferenceSetArgumentTrait.php
+++ b/src/Symfony/Component/DependencyInjection/Argument/ReferenceSetArgumentTrait.php
@@ -45,7 +45,7 @@ trait ReferenceSetArgumentTrait
     {
         foreach ($values as $k => $v) {
             if (null !== $v && !$v instanceof Reference) {
-                throw new InvalidArgumentException(sprintf('A %s must hold only Reference instances, "%s" given.', __CLASS__, is_object($v) ? get_class($v) : gettype($v)));
+                throw new InvalidArgumentException(sprintf('A %s must hold only Reference instances, "%s" given.', __CLASS__, \is_object($v) ? \get_class($v) : \gettype($v)));
             }
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Argument/RewindableGenerator.php b/src/Symfony/Component/DependencyInjection/Argument/RewindableGenerator.php
index e162a7c34d..f8f771d627 100644
--- a/src/Symfony/Component/DependencyInjection/Argument/RewindableGenerator.php
+++ b/src/Symfony/Component/DependencyInjection/Argument/RewindableGenerator.php
@@ -38,7 +38,7 @@ class RewindableGenerator implements \IteratorAggregate, \Countable
 
     public function count()
     {
-        if (is_callable($count = $this->count)) {
+        if (\is_callable($count = $this->count)) {
             $this->count = $count();
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/ChildDefinition.php b/src/Symfony/Component/DependencyInjection/ChildDefinition.php
index 0f67e960df..095beaec72 100644
--- a/src/Symfony/Component/DependencyInjection/ChildDefinition.php
+++ b/src/Symfony/Component/DependencyInjection/ChildDefinition.php
@@ -95,7 +95,7 @@ class ChildDefinition extends Definition
      */
     public function replaceArgument($index, $value)
     {
-        if (is_int($index)) {
+        if (\is_int($index)) {
             $this->arguments['index_'.$index] = $value;
         } elseif (0 === strpos($index, '$')) {
             $this->arguments[$index] = $value;
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/AbstractRecursivePass.php b/src/Symfony/Component/DependencyInjection/Compiler/AbstractRecursivePass.php
index ef50f8234e..9d543c0634 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/AbstractRecursivePass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/AbstractRecursivePass.php
@@ -103,8 +103,8 @@ abstract class AbstractRecursivePass implements CompilerPassInterface
      */
     protected function getConstructor(Definition $definition, $required)
     {
-        if (is_string($factory = $definition->getFactory())) {
-            if (!function_exists($factory)) {
+        if (\is_string($factory = $definition->getFactory())) {
+            if (!\function_exists($factory)) {
                 throw new RuntimeException(sprintf('Invalid service "%s": function "%s" does not exist.', $this->currentId, $factory));
             }
             $r = new \ReflectionFunction($factory);
@@ -196,7 +196,7 @@ abstract class AbstractRecursivePass implements CompilerPassInterface
                     $id = stripcslashes(substr($arg, 1, -1));
                     $arg = $this->processValue(new Reference($id), false, true);
                     if (!$arg instanceof Reference) {
-                        throw new RuntimeException(sprintf('"%s::processValue()" must return a Reference when processing an expression, %s returned for service("%s").', get_class($this), is_object($arg) ? get_class($arg) : gettype($arg)));
+                        throw new RuntimeException(sprintf('"%s::processValue()" must return a Reference when processing an expression, %s returned for service("%s").', \get_class($this), \is_object($arg) ? \get_class($arg) : \gettype($arg)));
                     }
                     $arg = sprintf('"%s"', $arg);
                 }
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/AutowirePass.php b/src/Symfony/Component/DependencyInjection/Compiler/AutowirePass.php
index fb8c135814..de7b661cad 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/AutowirePass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/AutowirePass.php
@@ -416,7 +416,7 @@ class AutowirePass extends AbstractRecursivePass
         }
 
         $extraContext = $extraContext ? ' '.$extraContext : '';
-        if (1 < $len = count($aliases)) {
+        if (1 < $len = \count($aliases)) {
             $message = sprintf('Try changing the type-hint%s to one of its parents: ', $extraContext);
             for ($i = 0, --$len; $i < $len; ++$i) {
                 $message .= sprintf('%s "%s", ', class_exists($aliases[$i], false) ? 'class' : 'interface', $aliases[$i]);
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/CheckArgumentsValidityPass.php b/src/Symfony/Component/DependencyInjection/Compiler/CheckArgumentsValidityPass.php
index 6e5e9042c8..e76e94005f 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/CheckArgumentsValidityPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/CheckArgumentsValidityPass.php
@@ -41,7 +41,7 @@ class CheckArgumentsValidityPass extends AbstractRecursivePass
         $i = 0;
         foreach ($value->getArguments() as $k => $v) {
             if ($k !== $i++) {
-                if (!is_int($k)) {
+                if (!\is_int($k)) {
                     $msg = sprintf('Invalid constructor argument for service "%s": integer expected but found string "%s". Check your service definition.', $this->currentId, $k);
                     $value->addError($msg);
                     if ($this->throwExceptions) {
@@ -63,7 +63,7 @@ class CheckArgumentsValidityPass extends AbstractRecursivePass
             $i = 0;
             foreach ($methodCall[1] as $k => $v) {
                 if ($k !== $i++) {
-                    if (!is_int($k)) {
+                    if (!\is_int($k)) {
                         $msg = sprintf('Invalid argument for method call "%s" of service "%s": integer expected but found string "%s". Check your service definition.', $methodCall[0], $this->currentId, $k);
                         $value->addError($msg);
                         if ($this->throwExceptions) {
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/CheckCircularReferencesPass.php b/src/Symfony/Component/DependencyInjection/Compiler/CheckCircularReferencesPass.php
index 6191893e03..5fe11bbd8c 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/CheckCircularReferencesPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/CheckCircularReferencesPass.php
@@ -64,7 +64,7 @@ class CheckCircularReferencesPass implements CompilerPassInterface
                     $this->currentPath[] = $id;
 
                     if (false !== $searchKey) {
-                        throw new ServiceCircularReferenceException($id, array_slice($this->currentPath, $searchKey));
+                        throw new ServiceCircularReferenceException($id, \array_slice($this->currentPath, $searchKey));
                     }
 
                     $this->checkOutEdges($node->getOutEdges());
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/Compiler.php b/src/Symfony/Component/DependencyInjection/Compiler/Compiler.php
index 7c797a92b3..b102e70641 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/Compiler.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/Compiler.php
@@ -69,10 +69,10 @@ class Compiler
     public function log(CompilerPassInterface $pass, string $message)
     {
         if (false !== strpos($message, "\n")) {
-            $message = str_replace("\n", "\n".get_class($pass).': ', trim($message));
+            $message = str_replace("\n", "\n".\get_class($pass).': ', trim($message));
         }
 
-        $this->log[] = get_class($pass).': '.$message;
+        $this->log[] = \get_class($pass).': '.$message;
     }
 
     /**
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/InlineServiceDefinitionsPass.php b/src/Symfony/Component/DependencyInjection/Compiler/InlineServiceDefinitionsPass.php
index 925081ef74..eb89a2a40d 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/InlineServiceDefinitionsPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/InlineServiceDefinitionsPass.php
@@ -139,7 +139,7 @@ class InlineServiceDefinitionsPass extends AbstractRecursivePass implements Repe
             $ids = array_keys($this->cloningIds);
             $ids[] = $id;
 
-            throw new ServiceCircularReferenceException($id, array_slice($ids, array_search($id, $ids)));
+            throw new ServiceCircularReferenceException($id, \array_slice($ids, array_search($id, $ids)));
         }
 
         $this->cloningIds[$id] = true;
@@ -204,7 +204,7 @@ class InlineServiceDefinitionsPass extends AbstractRecursivePass implements Repe
             return false;
         }
 
-        if ($srcCount > 1 && is_array($factory = $definition->getFactory()) && ($factory[0] instanceof Reference || $factory[0] instanceof Definition)) {
+        if ($srcCount > 1 && \is_array($factory = $definition->getFactory()) && ($factory[0] instanceof Reference || $factory[0] instanceof Definition)) {
             return false;
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/MergeExtensionConfigurationPass.php b/src/Symfony/Component/DependencyInjection/Compiler/MergeExtensionConfigurationPass.php
index 5312b4d46e..29063216ae 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/MergeExtensionConfigurationPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/MergeExtensionConfigurationPass.php
@@ -161,7 +161,7 @@ class MergeExtensionConfigurationContainerBuilder extends ContainerBuilder
     {
         parent::__construct($parameterBag);
 
-        $this->extensionClass = get_class($extension);
+        $this->extensionClass = \get_class($extension);
     }
 
     /**
@@ -169,7 +169,7 @@ class MergeExtensionConfigurationContainerBuilder extends ContainerBuilder
      */
     public function addCompilerPass(CompilerPassInterface $pass, $type = PassConfig::TYPE_BEFORE_OPTIMIZATION, int $priority = 0)
     {
-        throw new LogicException(sprintf('You cannot add compiler pass "%s" from extension "%s". Compiler passes must be registered before the container is compiled.', get_class($pass), $this->extensionClass));
+        throw new LogicException(sprintf('You cannot add compiler pass "%s" from extension "%s". Compiler passes must be registered before the container is compiled.', \get_class($pass), $this->extensionClass));
     }
 
     /**
@@ -177,7 +177,7 @@ class MergeExtensionConfigurationContainerBuilder extends ContainerBuilder
      */
     public function registerExtension(ExtensionInterface $extension)
     {
-        throw new LogicException(sprintf('You cannot register extension "%s" from "%s". Extensions must be registered before the container is compiled.', get_class($extension), $this->extensionClass));
+        throw new LogicException(sprintf('You cannot register extension "%s" from "%s". Extensions must be registered before the container is compiled.', \get_class($extension), $this->extensionClass));
     }
 
     /**
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/RegisterEnvVarProcessorsPass.php b/src/Symfony/Component/DependencyInjection/Compiler/RegisterEnvVarProcessorsPass.php
index 8ac301f192..297f806286 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/RegisterEnvVarProcessorsPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/RegisterEnvVarProcessorsPass.php
@@ -65,7 +65,7 @@ class RegisterEnvVarProcessorsPass implements CompilerPassInterface
         $types = explode('|', $types);
 
         foreach ($types as $type) {
-            if (!in_array($type, self::$allowedTypes)) {
+            if (!\in_array($type, self::$allowedTypes)) {
                 throw new InvalidArgumentException(sprintf('Invalid type "%s" returned by "%s::getProvidedTypes()", expected one of "%s".', $type, $class, implode('", "', self::$allowedTypes)));
             }
         }
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/RegisterServiceSubscribersPass.php b/src/Symfony/Component/DependencyInjection/Compiler/RegisterServiceSubscribersPass.php
index 87b4eac16c..4113509765 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/RegisterServiceSubscribersPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/RegisterServiceSubscribersPass.php
@@ -67,14 +67,14 @@ class RegisterServiceSubscribersPass extends AbstractRecursivePass
         $subscriberMap = array();
 
         foreach ($class::getSubscribedServices() as $key => $type) {
-            if (!is_string($type) || !preg_match('/^\??[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)*+$/', $type)) {
-                throw new InvalidArgumentException(sprintf('"%s::getSubscribedServices()" must return valid PHP types for service "%s" key "%s", "%s" returned.', $class, $this->currentId, $key, is_string($type) ? $type : gettype($type)));
+            if (!\is_string($type) || !preg_match('/^\??[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)*+$/', $type)) {
+                throw new InvalidArgumentException(sprintf('"%s::getSubscribedServices()" must return valid PHP types for service "%s" key "%s", "%s" returned.', $class, $this->currentId, $key, \is_string($type) ? $type : \gettype($type)));
             }
             if ($optionalBehavior = '?' === $type[0]) {
                 $type = substr($type, 1);
                 $optionalBehavior = ContainerInterface::IGNORE_ON_INVALID_REFERENCE;
             }
-            if (is_int($key)) {
+            if (\is_int($key)) {
                 $key = $type;
             }
             if (!isset($serviceMap[$key])) {
@@ -89,7 +89,7 @@ class RegisterServiceSubscribersPass extends AbstractRecursivePass
         }
 
         if ($serviceMap = array_keys($serviceMap)) {
-            $message = sprintf(1 < count($serviceMap) ? 'keys "%s" do' : 'key "%s" does', str_replace('%', '%%', implode('", "', $serviceMap)));
+            $message = sprintf(1 < \count($serviceMap) ? 'keys "%s" do' : 'key "%s" does', str_replace('%', '%%', implode('", "', $serviceMap)));
             throw new InvalidArgumentException(sprintf('Service %s not exist in the map returned by "%s::getSubscribedServices()" for service "%s".', $message, $class, $this->currentId));
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveBindingsPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveBindingsPass.php
index 7972fcffbe..a0c0d9f022 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveBindingsPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveBindingsPass.php
@@ -88,7 +88,7 @@ class ResolveBindingsPass extends AbstractRecursivePass
             }
 
             if (null !== $bindingValue && !$bindingValue instanceof Reference && !$bindingValue instanceof Definition) {
-                throw new InvalidArgumentException(sprintf('Invalid value for binding key "%s" for service "%s": expected null, an instance of %s or an instance of %s, %s given.', $key, $this->currentId, Reference::class, Definition::class, gettype($bindingValue)));
+                throw new InvalidArgumentException(sprintf('Invalid value for binding key "%s" for service "%s": expected null, an instance of %s or an instance of %s, %s given.', $key, $this->currentId, Reference::class, Definition::class, \gettype($bindingValue)));
             }
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveChildDefinitionsPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveChildDefinitionsPass.php
index 5dd766b3f1..11414811b2 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveChildDefinitionsPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveChildDefinitionsPass.php
@@ -147,7 +147,7 @@ class ResolveChildDefinitionsPass extends AbstractRecursivePass
             if (is_numeric($k)) {
                 $def->addArgument($v);
             } elseif (0 === strpos($k, 'index_')) {
-                $def->replaceArgument((int) substr($k, strlen('index_')), $v);
+                $def->replaceArgument((int) substr($k, \strlen('index_')), $v);
             } else {
                 $def->setArgument($k, $v);
             }
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveEnvPlaceholdersPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveEnvPlaceholdersPass.php
index f42107c6f7..9e1edd4d31 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveEnvPlaceholdersPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveEnvPlaceholdersPass.php
@@ -20,7 +20,7 @@ class ResolveEnvPlaceholdersPass extends AbstractRecursivePass
 {
     protected function processValue($value, $isRoot = false)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             return $this->container->resolveEnvPlaceholders($value, true);
         }
         if ($value instanceof Definition) {
@@ -35,7 +35,7 @@ class ResolveEnvPlaceholdersPass extends AbstractRecursivePass
 
         $value = parent::processValue($value, $isRoot);
 
-        if ($value && is_array($value) && !$isRoot) {
+        if ($value && \is_array($value) && !$isRoot) {
             $value = array_combine($this->container->resolveEnvPlaceholders(array_keys($value), true), $value);
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveFactoryClassPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveFactoryClassPass.php
index c41cf973fe..848da7f2bd 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveFactoryClassPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveFactoryClassPass.php
@@ -24,7 +24,7 @@ class ResolveFactoryClassPass extends AbstractRecursivePass
      */
     protected function processValue($value, $isRoot = false)
     {
-        if ($value instanceof Definition && is_array($factory = $value->getFactory()) && null === $factory[0]) {
+        if ($value instanceof Definition && \is_array($factory = $value->getFactory()) && null === $factory[0]) {
             if (null === $class = $value->getClass()) {
                 throw new RuntimeException(sprintf('The "%s" service is defined to be created by a factory, but is missing the factory class. Did you forget to define the factory or service class?', $this->currentId));
             }
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveInstanceofConditionalsPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveInstanceofConditionalsPass.php
index 63309b3a17..98bb366e9c 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveInstanceofConditionalsPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveInstanceofConditionalsPass.php
@@ -110,11 +110,11 @@ class ResolveInstanceofConditionalsPass implements CompilerPassInterface
                 $definition->setShared($shared);
             }
 
-            $i = count($instanceofTags);
+            $i = \count($instanceofTags);
             while (0 <= --$i) {
                 foreach ($instanceofTags[$i] as $k => $v) {
                     foreach ($v as $v) {
-                        if ($definition->hasTag($k) && in_array($v, $definition->getTag($k))) {
+                        if ($definition->hasTag($k) && \in_array($v, $definition->getTag($k))) {
                             continue;
                         }
                         $definition->addTag($k, $v);
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveInvalidReferencesPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveInvalidReferencesPass.php
index 97f4c1978d..cb5b4d21ea 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveInvalidReferencesPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveInvalidReferencesPass.php
@@ -66,7 +66,7 @@ class ResolveInvalidReferencesPass implements CompilerPassInterface
             $value->setArguments($this->processValue($value->getArguments(), 0));
             $value->setProperties($this->processValue($value->getProperties(), 1));
             $value->setMethodCalls($this->processValue($value->getMethodCalls(), 2));
-        } elseif (is_array($value)) {
+        } elseif (\is_array($value)) {
             $i = 0;
 
             foreach ($value as $k => $v) {
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveNamedArgumentsPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveNamedArgumentsPass.php
index 2dc53da89a..f9431b21d8 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveNamedArgumentsPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveNamedArgumentsPass.php
@@ -41,7 +41,7 @@ class ResolveNamedArgumentsPass extends AbstractRecursivePass
             $resolvedArguments = array();
 
             foreach ($arguments as $key => $argument) {
-                if (is_int($key)) {
+                if (\is_int($key)) {
                     $resolvedArguments[$key] = $argument;
                     continue;
                 }
@@ -71,7 +71,7 @@ class ResolveNamedArgumentsPass extends AbstractRecursivePass
                 }
 
                 if (null !== $argument && !$argument instanceof Reference && !$argument instanceof Definition) {
-                    throw new InvalidArgumentException(sprintf('Invalid service "%s": the value of argument "%s" of method "%s()" must be null, an instance of %s or an instance of %s, %s given.', $this->currentId, $key, $class !== $this->currentId ? $class.'::'.$method : $method, Reference::class, Definition::class, gettype($argument)));
+                    throw new InvalidArgumentException(sprintf('Invalid service "%s": the value of argument "%s" of method "%s()" must be null, an instance of %s or an instance of %s, %s given.', $this->currentId, $key, $class !== $this->currentId ? $class.'::'.$method : $method, Reference::class, Definition::class, \gettype($argument)));
                 }
 
                 $typeFound = false;
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ResolveParameterPlaceHoldersPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ResolveParameterPlaceHoldersPass.php
index 3988f6dc27..de16102d46 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ResolveParameterPlaceHoldersPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ResolveParameterPlaceHoldersPass.php
@@ -60,10 +60,10 @@ class ResolveParameterPlaceHoldersPass extends AbstractRecursivePass
 
     protected function processValue($value, $isRoot = false)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             $v = $this->bag->resolveValue($value);
 
-            return $this->resolveArrays || !$v || !is_array($v) ? $v : $value;
+            return $this->resolveArrays || !$v || !\is_array($v) ? $v : $value;
         }
         if ($value instanceof Definition) {
             $value->setBindings($this->processValue($value->getBindings()));
@@ -78,7 +78,7 @@ class ResolveParameterPlaceHoldersPass extends AbstractRecursivePass
 
         $value = parent::processValue($value, $isRoot);
 
-        if ($value && is_array($value)) {
+        if ($value && \is_array($value)) {
             $value = array_combine($this->bag->resolveValue(array_keys($value)), $value);
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Compiler/ServiceLocatorTagPass.php b/src/Symfony/Component/DependencyInjection/Compiler/ServiceLocatorTagPass.php
index f712c317f3..023ff552a1 100644
--- a/src/Symfony/Component/DependencyInjection/Compiler/ServiceLocatorTagPass.php
+++ b/src/Symfony/Component/DependencyInjection/Compiler/ServiceLocatorTagPass.php
@@ -41,7 +41,7 @@ final class ServiceLocatorTagPass extends AbstractRecursivePass
         }
 
         $arguments = $value->getArguments();
-        if (!isset($arguments[0]) || !is_array($arguments[0])) {
+        if (!isset($arguments[0]) || !\is_array($arguments[0])) {
             throw new InvalidArgumentException(sprintf('Invalid definition for service "%s": an array of references is expected as first argument when the "container.service_locator" tag is set.', $this->currentId));
         }
 
@@ -50,7 +50,7 @@ final class ServiceLocatorTagPass extends AbstractRecursivePass
                 continue;
             }
             if (!$v instanceof Reference) {
-                throw new InvalidArgumentException(sprintf('Invalid definition for service "%s": an array of references is expected as first argument when the "container.service_locator" tag is set, "%s" found for key "%s".', $this->currentId, is_object($v) ? get_class($v) : gettype($v), $k));
+                throw new InvalidArgumentException(sprintf('Invalid definition for service "%s": an array of references is expected as first argument when the "container.service_locator" tag is set, "%s" found for key "%s".', $this->currentId, \is_object($v) ? \get_class($v) : \gettype($v), $k));
             }
             $arguments[0][$k] = new ServiceClosureArgument($v);
         }
@@ -84,7 +84,7 @@ final class ServiceLocatorTagPass extends AbstractRecursivePass
     {
         foreach ($refMap as $id => $ref) {
             if (!$ref instanceof Reference) {
-                throw new InvalidArgumentException(sprintf('Invalid service locator definition: only services can be referenced, "%s" found for key "%s". Inject parameter values using constructors instead.', is_object($ref) ? get_class($ref) : gettype($ref), $id));
+                throw new InvalidArgumentException(sprintf('Invalid service locator definition: only services can be referenced, "%s" found for key "%s". Inject parameter values using constructors instead.', \is_object($ref) ? \get_class($ref) : \gettype($ref), $id));
             }
             $refMap[$id] = new ServiceClosureArgument($ref);
         }
diff --git a/src/Symfony/Component/DependencyInjection/Container.php b/src/Symfony/Component/DependencyInjection/Container.php
index 2eaa278cdb..f627a57eff 100644
--- a/src/Symfony/Component/DependencyInjection/Container.php
+++ b/src/Symfony/Component/DependencyInjection/Container.php
@@ -267,7 +267,7 @@ class Container implements ResettableContainerInterface
                     continue;
                 }
                 $lev = levenshtein($id, $knownId);
-                if ($lev <= strlen($id) / 3 || false !== strpos($knownId, $id)) {
+                if ($lev <= \strlen($id) / 3 || false !== strpos($knownId, $id)) {
                     $alternatives[] = $knownId;
                 }
             }
diff --git a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
index dad23cf3bb..3a79b17e07 100644
--- a/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
+++ b/src/Symfony/Component/DependencyInjection/ContainerBuilder.php
@@ -294,8 +294,8 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
     public function addObjectResource($object)
     {
         if ($this->trackResources) {
-            if (is_object($object)) {
-                $object = get_class($object);
+            if (\is_object($object)) {
+                $object = \get_class($object);
             }
             if (!isset($this->classReflectors[$object])) {
                 $this->classReflectors[$object] = new \ReflectionClass($object);
@@ -403,7 +403,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
 
         if (is_dir($path)) {
             if ($trackContents) {
-                $this->addResource(new DirectoryResource($path, is_string($trackContents) ? $trackContents : null));
+                $this->addResource(new DirectoryResource($path, \is_string($trackContents) ? $trackContents : null));
             } else {
                 $this->addResource(new GlobResource($path, '/*', false));
             }
@@ -431,7 +431,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
             throw new BadMethodCallException('Cannot load from an extension on a compiled container.');
         }
 
-        if (func_num_args() < 2) {
+        if (\func_num_args() < 2) {
             $values = array();
         }
 
@@ -816,7 +816,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
     {
         $alias = (string) $alias;
 
-        if (is_string($id)) {
+        if (\is_string($id)) {
             $id = new Alias($id);
         } elseif (!$id instanceof Alias) {
             throw new InvalidArgumentException('$id must be a string, or an Alias object.');
@@ -1027,7 +1027,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
 
             if (isset($seen[$id])) {
                 $seen = array_values($seen);
-                $seen = array_slice($seen, array_search($id, $seen));
+                $seen = \array_slice($seen, array_search($id, $seen));
                 $seen[] = $id;
 
                 throw new ServiceCircularReferenceException($id, $seen);
@@ -1098,15 +1098,15 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
         }
 
         if (null !== $factory = $definition->getFactory()) {
-            if (is_array($factory)) {
+            if (\is_array($factory)) {
                 $factory = array($this->doResolveServices($parameterBag->resolveValue($factory[0]), $inlineServices), $factory[1]);
-            } elseif (!is_string($factory)) {
+            } elseif (!\is_string($factory)) {
                 throw new RuntimeException(sprintf('Cannot create service "%s" because of invalid factory', $id));
             }
 
-            $service = call_user_func_array($factory, $arguments);
+            $service = \call_user_func_array($factory, $arguments);
 
-            if (!$definition->isDeprecated() && is_array($factory) && is_string($factory[0])) {
+            if (!$definition->isDeprecated() && \is_array($factory) && \is_string($factory[0])) {
                 $r = new \ReflectionClass($factory[0]);
 
                 if (0 < strpos($r->getDocComment(), "\n * @deprecated ")) {
@@ -1138,7 +1138,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
         }
 
         if ($callable = $definition->getConfigurator()) {
-            if (is_array($callable)) {
+            if (\is_array($callable)) {
                 $callable[0] = $parameterBag->resolveValue($callable[0]);
 
                 if ($callable[0] instanceof Reference) {
@@ -1148,11 +1148,11 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
                 }
             }
 
-            if (!is_callable($callable)) {
-                throw new InvalidArgumentException(sprintf('The configure callable for class "%s" is not a callable.', get_class($service)));
+            if (!\is_callable($callable)) {
+                throw new InvalidArgumentException(sprintf('The configure callable for class "%s" is not a callable.', \get_class($service)));
             }
 
-            call_user_func($callable, $service);
+            \call_user_func($callable, $service);
         }
 
         return $service;
@@ -1173,7 +1173,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
 
     private function doResolveServices($value, array &$inlineServices = array())
     {
-        if (is_array($value)) {
+        if (\is_array($value)) {
             foreach ($value as $k => $v) {
                 $value[$k] = $this->doResolveServices($v, $inlineServices);
             }
@@ -1386,8 +1386,8 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
                         $value = $resolved;
                         $completed = true;
                     } else {
-                        if (!is_string($resolved) && !is_numeric($resolved)) {
-                            throw new RuntimeException(sprintf('A string value must be composed of strings and/or numbers, but found parameter "env(%s)" of type %s inside string value "%s".', $env, gettype($resolved), $this->resolveEnvPlaceholders($value)));
+                        if (!\is_string($resolved) && !is_numeric($resolved)) {
+                            throw new RuntimeException(sprintf('A string value must be composed of strings and/or numbers, but found parameter "env(%s)" of type %s inside string value "%s".', $env, \gettype($resolved), $this->resolveEnvPlaceholders($value)));
                         }
                         $value = str_ireplace($placeholder, $resolved, $value);
                     }
@@ -1444,7 +1444,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
     {
         $services = array();
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             foreach ($value as $v) {
                 $services = array_unique(array_merge($services, self::getServiceConditionals($v)));
             }
@@ -1468,7 +1468,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
     {
         $services = array();
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             foreach ($value as $v) {
                 $services = array_unique(array_merge($services, self::getInitializedConditionals($v)));
             }
@@ -1501,7 +1501,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
         $value = parent::getEnv($name);
         $bag = $this->getParameterBag();
 
-        if (!is_string($value) || !$bag instanceof EnvPlaceholderParameterBag) {
+        if (!\is_string($value) || !$bag instanceof EnvPlaceholderParameterBag) {
             return $value;
         }
 
@@ -1546,7 +1546,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
             }
         }
 
-        call_user_func_array(array($service, $call[0]), $this->doResolveServices($this->getParameterBag()->unescapeValue($this->getParameterBag()->resolveValue($call[1])), $inlineServices));
+        \call_user_func_array(array($service, $call[0]), $this->doResolveServices($this->getParameterBag()->unescapeValue($this->getParameterBag()->resolveValue($call[1])), $inlineServices));
     }
 
     /**
@@ -1588,7 +1588,7 @@ class ContainerBuilder extends Container implements TaggedContainerInterface
         $path = realpath($path) ?: $path;
 
         foreach ($this->vendors as $vendor) {
-            if (0 === strpos($path, $vendor) && false !== strpbrk(substr($path, strlen($vendor), 1), '/'.DIRECTORY_SEPARATOR)) {
+            if (0 === strpos($path, $vendor) && false !== strpbrk(substr($path, \strlen($vendor), 1), '/'.DIRECTORY_SEPARATOR)) {
                 return true;
             }
         }
diff --git a/src/Symfony/Component/DependencyInjection/Definition.php b/src/Symfony/Component/DependencyInjection/Definition.php
index 807ce13a07..7301901beb 100644
--- a/src/Symfony/Component/DependencyInjection/Definition.php
+++ b/src/Symfony/Component/DependencyInjection/Definition.php
@@ -103,7 +103,7 @@ class Definition
     {
         $this->changes['factory'] = true;
 
-        if (is_string($factory) && false !== strpos($factory, '::')) {
+        if (\is_string($factory) && false !== strpos($factory, '::')) {
             $factory = explode('::', $factory, 2);
         }
 
@@ -261,12 +261,12 @@ class Definition
      */
     public function replaceArgument($index, $argument)
     {
-        if (0 === count($this->arguments)) {
+        if (0 === \count($this->arguments)) {
             throw new OutOfBoundsException('Cannot replace arguments if none have been configured yet.');
         }
 
-        if (is_int($index) && ($index < 0 || $index > count($this->arguments) - 1)) {
-            throw new OutOfBoundsException(sprintf('The index "%d" is not in the range [0, %d].', $index, count($this->arguments) - 1));
+        if (\is_int($index) && ($index < 0 || $index > \count($this->arguments) - 1)) {
+            throw new OutOfBoundsException(sprintf('The index "%d" is not in the range [0, %d].', $index, \count($this->arguments) - 1));
         }
 
         if (!array_key_exists($index, $this->arguments)) {
@@ -790,7 +790,7 @@ class Definition
     {
         $this->changes['configurator'] = true;
 
-        if (is_string($configurator) && false !== strpos($configurator, '::')) {
+        if (\is_string($configurator) && false !== strpos($configurator, '::')) {
             $configurator = explode('::', $configurator, 2);
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Dumper/GraphvizDumper.php b/src/Symfony/Component/DependencyInjection/Dumper/GraphvizDumper.php
index 84cc1f59a5..7606f60b0a 100644
--- a/src/Symfony/Component/DependencyInjection/Dumper/GraphvizDumper.php
+++ b/src/Symfony/Component/DependencyInjection/Dumper/GraphvizDumper.php
@@ -116,7 +116,7 @@ class GraphvizDumper extends Dumper
         foreach ($arguments as $argument) {
             if ($argument instanceof Parameter) {
                 $argument = $this->container->hasParameter($argument) ? $this->container->getParameter($argument) : null;
-            } elseif (is_string($argument) && preg_match('/^%([^%]+)%$/', $argument, $match)) {
+            } elseif (\is_string($argument) && preg_match('/^%([^%]+)%$/', $argument, $match)) {
                 $argument = $this->container->hasParameter($match[1]) ? $this->container->getParameter($match[1]) : null;
             }
 
@@ -132,7 +132,7 @@ class GraphvizDumper extends Dumper
                 $edges[] = array('name' => $name, 'required' => $required, 'to' => $argument, 'lazy' => $lazyEdge);
             } elseif ($argument instanceof ArgumentInterface) {
                 $edges = array_merge($edges, $this->findEdges($id, $argument->getValues(), $required, $name, true));
-            } elseif (is_array($argument)) {
+            } elseif (\is_array($argument)) {
                 $edges = array_merge($edges, $this->findEdges($id, $argument, $required, $name, $lazy));
             }
         }
@@ -168,7 +168,7 @@ class GraphvizDumper extends Dumper
             }
 
             if (!$container->hasDefinition($id)) {
-                $nodes[$id] = array('class' => str_replace('\\', '\\\\', get_class($container->get($id))), 'attributes' => $this->options['node.instance']);
+                $nodes[$id] = array('class' => str_replace('\\', '\\\\', \get_class($container->get($id))), 'attributes' => $this->options['node.instance']);
             }
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Dumper/PhpDumper.php b/src/Symfony/Component/DependencyInjection/Dumper/PhpDumper.php
index 648cbe7237..4da2929c3f 100644
--- a/src/Symfony/Component/DependencyInjection/Dumper/PhpDumper.php
+++ b/src/Symfony/Component/DependencyInjection/Dumper/PhpDumper.php
@@ -166,13 +166,13 @@ class PhpDumper extends Dumper
 
         $this->docStar = $options['debug'] ? '*' : '';
 
-        if (!empty($options['file']) && is_dir($dir = dirname($options['file']))) {
+        if (!empty($options['file']) && is_dir($dir = \dirname($options['file']))) {
             // Build a regexp where the first root dirs are mandatory,
             // but every other sub-dir is optional up to the full path in $dir
             // Mandate at least 2 root dirs and not more that 5 optional dirs.
 
             $dir = explode(DIRECTORY_SEPARATOR, realpath($dir));
-            $i = count($dir);
+            $i = \count($dir);
 
             if (3 <= $i) {
                 $regex = '';
@@ -446,7 +446,7 @@ EOTXT
         if ($this->inlineRequires && !$this->isHotPath($definition)) {
             $lineage = $calls = $behavior = array();
             foreach ($inlinedDefinitions as $def) {
-                if (!$def->isDeprecated() && is_string($class = is_array($factory = $def->getFactory()) && is_string($factory[0]) ? $factory[0] : $def->getClass())) {
+                if (!$def->isDeprecated() && \is_string($class = \is_array($factory = $def->getFactory()) && \is_string($factory[0]) ? $factory[0] : $def->getClass())) {
                     $this->collectLineage($class, $lineage);
                 }
                 $arguments = array($def->getArguments(), $def->getFactory(), $def->getProperties(), $def->getMethodCalls(), $def->getConfigurator());
@@ -458,7 +458,7 @@ EOTXT
                     && ContainerInterface::IGNORE_ON_UNINITIALIZED_REFERENCE !== $behavior[$id]
                     && $this->container->has($id)
                     && $this->isTrivialInstance($def = $this->container->findDefinition($id))
-                    && is_string($class = is_array($factory = $def->getFactory()) && is_string($factory[0]) ? $factory[0] : $def->getClass())
+                    && \is_string($class = \is_array($factory = $def->getFactory()) && \is_string($factory[0]) ? $factory[0] : $def->getClass())
                 ) {
                     $this->collectLineage($class, $lineage);
                 }
@@ -578,7 +578,7 @@ EOTXT
         if ($definition->isSynthetic() || $definition->getFile() || $definition->getMethodCalls() || $definition->getProperties() || $definition->getConfigurator()) {
             return false;
         }
-        if ($definition->isDeprecated() || $definition->isLazy() || $definition->getFactory() || 3 < count($definition->getArguments())) {
+        if ($definition->isDeprecated() || $definition->isLazy() || $definition->getFactory() || 3 < \count($definition->getArguments())) {
             return false;
         }
 
@@ -586,7 +586,7 @@ EOTXT
             if (!$arg || $arg instanceof Parameter) {
                 continue;
             }
-            if (is_array($arg) && 3 >= count($arg)) {
+            if (\is_array($arg) && 3 >= \count($arg)) {
                 foreach ($arg as $k => $v) {
                     if ($this->dumpValue($k) !== $this->dumpValue($k, false)) {
                         return false;
@@ -678,7 +678,7 @@ EOTXT
             return '';
         }
 
-        if (is_array($callable)) {
+        if (\is_array($callable)) {
             if ($callable[0] instanceof Reference
                 || ($callable[0] instanceof Definition && $this->definitionVariables->contains($callable[0]))) {
                 return sprintf("        %s->%s(\$%s);\n", $this->dumpValue($callable[0]), $callable[1], $variableName);
@@ -713,10 +713,10 @@ EOTXT
             $return[] = sprintf(0 === strpos($class, '%') ? '@return object A %1$s instance' : '@return \%s', ltrim($class, '\\'));
         } elseif ($definition->getFactory()) {
             $factory = $definition->getFactory();
-            if (is_string($factory)) {
+            if (\is_string($factory)) {
                 $return[] = sprintf('@return object An instance returned by %s()', $factory);
-            } elseif (is_array($factory) && (is_string($factory[0]) || $factory[0] instanceof Definition || $factory[0] instanceof Reference)) {
-                if (is_string($factory[0]) || $factory[0] instanceof Reference) {
+            } elseif (\is_array($factory) && (\is_string($factory[0]) || $factory[0] instanceof Definition || $factory[0] instanceof Reference)) {
+                if (\is_string($factory[0]) || $factory[0] instanceof Reference) {
                     $return[] = sprintf('@return object An instance returned by %s::%s()', (string) $factory[0], $factory[1]);
                 } elseif ($factory[0] instanceof Definition) {
                     $return[] = sprintf('@return object An instance returned by %s::%s()', $factory[0]->getClass(), $factory[1]);
@@ -725,7 +725,7 @@ EOTXT
         }
 
         if ($definition->isDeprecated()) {
-            if ($return && 0 === strpos($return[count($return) - 1], '@return')) {
+            if ($return && 0 === strpos($return[\count($return) - 1], '@return')) {
                 $return[] = '';
             }
 
@@ -880,7 +880,7 @@ EOF;
         if (null !== $definition->getFactory()) {
             $callable = $definition->getFactory();
 
-            if (is_array($callable)) {
+            if (\is_array($callable)) {
                 if (!preg_match('/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*$/', $callable[1])) {
                     throw new RuntimeException(sprintf('Cannot dump definition because of invalid factory method (%s)', $callable[1] ?: 'n/a'));
                 }
@@ -1161,7 +1161,7 @@ EOF;
             $inlinedDefinitions = $this->getDefinitionsFromArguments(array($definition));
 
             foreach ($inlinedDefinitions as $def) {
-                if (is_string($class = is_array($factory = $def->getFactory()) && is_string($factory[0]) ? $factory[0] : $def->getClass())) {
+                if (\is_string($class = \is_array($factory = $def->getFactory()) && \is_string($factory[0]) ? $factory[0] : $def->getClass())) {
                     $this->collectLineage($class, $lineage);
                 }
             }
@@ -1259,7 +1259,7 @@ EOF;
         }
 
         if ($dynamicPhp) {
-            $loadedDynamicParameters = $this->exportParameters(array_combine(array_keys($dynamicPhp), array_fill(0, count($dynamicPhp), false)), '', 8);
+            $loadedDynamicParameters = $this->exportParameters(array_combine(array_keys($dynamicPhp), array_fill(0, \count($dynamicPhp), false)), '', 8);
             $getDynamicParameter = <<<'EOF'
         switch ($name) {
 %s
@@ -1316,10 +1316,10 @@ EOF;
     {
         $php = array();
         foreach ($parameters as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $value = $this->exportParameters($value, $path.'/'.$key, $indent + 4);
             } elseif ($value instanceof ArgumentInterface) {
-                throw new InvalidArgumentException(sprintf('You cannot dump a container with parameters that contain special arguments. "%s" found in "%s".', get_class($value), $path.'/'.$key));
+                throw new InvalidArgumentException(sprintf('You cannot dump a container with parameters that contain special arguments. "%s" found in "%s".', \get_class($value), $path.'/'.$key));
             } elseif ($value instanceof Variable) {
                 throw new InvalidArgumentException(sprintf('You cannot dump a container with parameters that contain variable references. Variable "%s" found in "%s".', $value, $path.'/'.$key));
             } elseif ($value instanceof Definition) {
@@ -1397,7 +1397,7 @@ EOF;
     private function getServiceCallsFromArguments(array $arguments, array &$calls, bool $isPreInstance, string $callerId, array &$behavior = array(), int $step = 1)
     {
         foreach ($arguments as $argument) {
-            if (is_array($argument)) {
+            if (\is_array($argument)) {
                 $this->getServiceCallsFromArguments($argument, $calls, $isPreInstance, $callerId, $behavior, $step);
             } elseif ($argument instanceof Reference) {
                 $id = (string) $argument;
@@ -1423,7 +1423,7 @@ EOF;
         }
 
         foreach ($arguments as $argument) {
-            if (is_array($argument)) {
+            if (\is_array($argument)) {
                 $this->getDefinitionsFromArguments($argument, $definitions);
             } elseif (!$argument instanceof Definition) {
                 // no-op
@@ -1453,7 +1453,7 @@ EOF;
         }
 
         foreach ($arguments as $argument) {
-            if (is_array($argument)) {
+            if (\is_array($argument)) {
                 if ($this->hasReference($id, $argument, $deep, $visited)) {
                     return true;
                 }
@@ -1497,7 +1497,7 @@ EOF;
      */
     private function dumpValue($value, bool $interpolate = true): string
     {
-        if (is_array($value)) {
+        if (\is_array($value)) {
             if ($value && $interpolate && false !== $param = array_search($value, $this->container->getParameterBag()->all(), true)) {
                 return $this->dumpValue("%$param%");
             }
@@ -1551,7 +1551,7 @@ EOF;
                         $countCode[] = '        }';
                     }
 
-                    $code[] = sprintf('        }, %s)', count($operands) > 1 ? implode("\n", $countCode) : $operands[0]);
+                    $code[] = sprintf('        }, %s)', \count($operands) > 1 ? implode("\n", $countCode) : $operands[0]);
 
                     return implode("\n", $code);
                 }
@@ -1612,7 +1612,7 @@ EOF;
             return $this->getExpressionLanguage()->compile((string) $value, array('this' => 'container'));
         } elseif ($value instanceof Parameter) {
             return $this->dumpParameter($value);
-        } elseif (true === $interpolate && is_string($value)) {
+        } elseif (true === $interpolate && \is_string($value)) {
             if (preg_match('/^%([^%]+)%$/', $value, $match)) {
                 // we do this to deal with non string values (Boolean, integer, ...)
                 // the preg_replace_callback converts them to strings
@@ -1626,7 +1626,7 @@ EOF;
 
                 return $code;
             }
-        } elseif (is_object($value) || is_resource($value)) {
+        } elseif (\is_object($value) || \is_resource($value)) {
             throw new RuntimeException('Unable to dump a service container if a parameter is an object or a resource.');
         }
 
@@ -1658,7 +1658,7 @@ EOF;
             $value = $this->container->getParameter($name);
             $dumpedValue = $this->dumpValue($value, false);
 
-            if (!$value || !is_array($value)) {
+            if (!$value || !\is_array($value)) {
                 return $dumpedValue;
             }
 
@@ -1769,9 +1769,9 @@ EOF;
     private function getNextVariableName(): string
     {
         $firstChars = self::FIRST_CHARS;
-        $firstCharsLength = strlen($firstChars);
+        $firstCharsLength = \strlen($firstChars);
         $nonFirstChars = self::NON_FIRST_CHARS;
-        $nonFirstCharsLength = strlen($nonFirstChars);
+        $nonFirstCharsLength = \strlen($nonFirstChars);
 
         while (true) {
             $name = '';
@@ -1791,7 +1791,7 @@ EOF;
             ++$this->variableCount;
 
             // check that the name is not reserved
-            if (in_array($name, $this->reservedVariables, true)) {
+            if (\in_array($name, $this->reservedVariables, true)) {
                 continue;
             }
 
@@ -1852,12 +1852,12 @@ EOF;
 
     private function export($value)
     {
-        if (null !== $this->targetDirRegex && is_string($value) && preg_match($this->targetDirRegex, $value, $matches, PREG_OFFSET_CAPTURE)) {
+        if (null !== $this->targetDirRegex && \is_string($value) && preg_match($this->targetDirRegex, $value, $matches, PREG_OFFSET_CAPTURE)) {
             $prefix = $matches[0][1] ? $this->doExport(substr($value, 0, $matches[0][1]), true).'.' : '';
-            $suffix = $matches[0][1] + strlen($matches[0][0]);
+            $suffix = $matches[0][1] + \strlen($matches[0][0]);
             $suffix = isset($value[$suffix]) ? '.'.$this->doExport(substr($value, $suffix), true) : '';
             $dirname = $this->asFiles ? '$this->containerDir' : '__DIR__';
-            $offset = 1 + $this->targetDirMaxMatches - count($matches);
+            $offset = 1 + $this->targetDirMaxMatches - \count($matches);
 
             if ($this->asFiles || 0 < $offset) {
                 $dirname = sprintf('$this->targetDirs[%d]', $offset);
@@ -1875,7 +1875,7 @@ EOF;
 
     private function doExport($value, $resolveEnv = false)
     {
-        if (is_string($value) && false !== strpos($value, "\n")) {
+        if (\is_string($value) && false !== strpos($value, "\n")) {
             $cleanParts = explode("\n", $value);
             $cleanParts = array_map(function ($part) { return var_export($part, true); }, $cleanParts);
             $export = implode('."\n".', $cleanParts);
diff --git a/src/Symfony/Component/DependencyInjection/Dumper/XmlDumper.php b/src/Symfony/Component/DependencyInjection/Dumper/XmlDumper.php
index a644ff3fc2..985240e741 100644
--- a/src/Symfony/Component/DependencyInjection/Dumper/XmlDumper.php
+++ b/src/Symfony/Component/DependencyInjection/Dumper/XmlDumper.php
@@ -81,7 +81,7 @@ class XmlDumper extends Dumper
         foreach ($methodcalls as $methodcall) {
             $call = $this->document->createElement('call');
             $call->setAttribute('method', $methodcall[0]);
-            if (count($methodcall[1])) {
+            if (\count($methodcall[1])) {
                 $this->convertParameters($methodcall[1], 'argument', $call);
             }
             $parent->appendChild($call);
@@ -161,10 +161,10 @@ class XmlDumper extends Dumper
         if ($callable = $definition->getFactory()) {
             $factory = $this->document->createElement('factory');
 
-            if (is_array($callable) && $callable[0] instanceof Definition) {
+            if (\is_array($callable) && $callable[0] instanceof Definition) {
                 $this->addService($callable[0], null, $factory);
                 $factory->setAttribute('method', $callable[1]);
-            } elseif (is_array($callable)) {
+            } elseif (\is_array($callable)) {
                 if (null !== $callable[0]) {
                     $factory->setAttribute($callable[0] instanceof Reference ? 'service' : 'class', $callable[0]);
                 }
@@ -197,10 +197,10 @@ class XmlDumper extends Dumper
         if ($callable = $definition->getConfigurator()) {
             $configurator = $this->document->createElement('configurator');
 
-            if (is_array($callable) && $callable[0] instanceof Definition) {
+            if (\is_array($callable) && $callable[0] instanceof Definition) {
                 $this->addService($callable[0], null, $configurator);
                 $configurator->setAttribute('method', $callable[1]);
-            } elseif (is_array($callable)) {
+            } elseif (\is_array($callable)) {
                 $configurator->setAttribute($callable[0] instanceof Reference ? 'service' : 'class', $callable[0]);
                 $configurator->setAttribute('method', $callable[1]);
             } else {
@@ -262,7 +262,7 @@ class XmlDumper extends Dumper
      */
     private function convertParameters(array $parameters, $type, \DOMElement $parent, $keyAttribute = 'key')
     {
-        $withKeys = array_keys($parameters) !== range(0, count($parameters) - 1);
+        $withKeys = array_keys($parameters) !== range(0, \count($parameters) - 1);
         foreach ($parameters as $key => $value) {
             $element = $this->document->createElement($type);
             if ($withKeys) {
@@ -272,7 +272,7 @@ class XmlDumper extends Dumper
             if ($value instanceof ServiceClosureArgument) {
                 $value = $value->getValues()[0];
             }
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $element->setAttribute('type', 'collection');
                 $this->convertParameters($value, $type, $element, 'key');
             } elseif ($value instanceof TaggedIteratorArgument) {
@@ -307,7 +307,7 @@ class XmlDumper extends Dumper
                 $text = $this->document->createTextNode(self::phpToXml(base64_encode($value)));
                 $element->appendChild($text);
             } else {
-                if (in_array($value, array('null', 'true', 'false'), true)) {
+                if (\in_array($value, array('null', 'true', 'false'), true)) {
                     $element->setAttribute('type', 'string');
                 }
                 $text = $this->document->createTextNode(self::phpToXml($value));
@@ -326,9 +326,9 @@ class XmlDumper extends Dumper
     {
         $args = array();
         foreach ($arguments as $k => $v) {
-            if (is_array($v)) {
+            if (\is_array($v)) {
                 $args[$k] = $this->escape($v);
-            } elseif (is_string($v)) {
+            } elseif (\is_string($v)) {
                 $args[$k] = str_replace('%', '%%', $v);
             } else {
                 $args[$k] = $v;
@@ -358,7 +358,7 @@ class XmlDumper extends Dumper
                 return 'false';
             case $value instanceof Parameter:
                 return '%'.$value.'%';
-            case is_object($value) || is_resource($value):
+            case \is_object($value) || \is_resource($value):
                 throw new RuntimeException('Unable to dump a service container if a parameter is an object or a resource.');
             default:
                 return (string) $value;
diff --git a/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php b/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
index ce53c602db..9322abea1b 100644
--- a/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
+++ b/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
@@ -203,7 +203,7 @@ class YamlDumper extends Dumper
      */
     private function dumpCallable($callable)
     {
-        if (is_array($callable)) {
+        if (\is_array($callable)) {
             if ($callable[0] instanceof Reference) {
                 $callable = array($this->getServiceCall((string) $callable[0], $callable[0]), $callable[1]);
             } else {
@@ -237,13 +237,13 @@ class YamlDumper extends Dumper
             } elseif ($value instanceof ServiceLocatorArgument) {
                 $tag = 'service_locator';
             } else {
-                throw new RuntimeException(sprintf('Unspecified Yaml tag for type "%s".', get_class($value)));
+                throw new RuntimeException(sprintf('Unspecified Yaml tag for type "%s".', \get_class($value)));
             }
 
             return new TaggedValue($tag, $this->dumpValue($value->getValues()));
         }
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             $code = array();
             foreach ($value as $k => $v) {
                 $code[$k] = $this->dumpValue($v);
@@ -258,7 +258,7 @@ class YamlDumper extends Dumper
             return $this->getExpressionCall((string) $value);
         } elseif ($value instanceof Definition) {
             return new TaggedValue('service', (new Parser())->parse("_:\n".$this->addService('_', $value), Yaml::PARSE_CUSTOM_TAGS)['_']['_']);
-        } elseif (is_object($value) || is_resource($value)) {
+        } elseif (\is_object($value) || \is_resource($value)) {
             throw new RuntimeException('Unable to dump a service container if a parameter is an object or a resource.');
         }
 
@@ -293,9 +293,9 @@ class YamlDumper extends Dumper
     {
         $filtered = array();
         foreach ($parameters as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $value = $this->prepareParameters($value, $escape);
-            } elseif ($value instanceof Reference || is_string($value) && 0 === strpos($value, '@')) {
+            } elseif ($value instanceof Reference || \is_string($value) && 0 === strpos($value, '@')) {
                 $value = '@'.$value;
             }
 
@@ -309,9 +309,9 @@ class YamlDumper extends Dumper
     {
         $args = array();
         foreach ($arguments as $k => $v) {
-            if (is_array($v)) {
+            if (\is_array($v)) {
                 $args[$k] = $this->escape($v);
-            } elseif (is_string($v)) {
+            } elseif (\is_string($v)) {
                 $args[$k] = str_replace('%', '%%', $v);
             } else {
                 $args[$k] = $v;
diff --git a/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php b/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php
index e91df9670b..a33d3932af 100644
--- a/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php
+++ b/src/Symfony/Component/DependencyInjection/EnvVarProcessor.php
@@ -63,7 +63,7 @@ class EnvVarProcessor implements EnvVarProcessorInterface
             $key = substr($name, 0, $i);
             $array = $getEnv($next);
 
-            if (!is_array($array)) {
+            if (!\is_array($array)) {
                 throw new RuntimeException(sprintf('Resolved value of "%s" did not result in an array value.', $next));
             }
             if (!array_key_exists($key, $array)) {
@@ -131,11 +131,11 @@ class EnvVarProcessor implements EnvVarProcessorInterface
         }
 
         if ('const' === $prefix) {
-            if (!defined($env)) {
+            if (!\defined($env)) {
                 throw new RuntimeException(sprintf('Env var "%s" maps to undefined constant "%s".', $name, $env));
             }
 
-            return constant($env);
+            return \constant($env);
         }
 
         if ('base64' === $prefix) {
@@ -149,8 +149,8 @@ class EnvVarProcessor implements EnvVarProcessorInterface
                 throw new RuntimeException(sprintf('Invalid JSON in env var "%s": '.json_last_error_msg(), $name));
             }
 
-            if (null !== $env && !is_array($env)) {
-                throw new RuntimeException(sprintf('Invalid JSON env var "%s": array or null expected, %s given.', $name, gettype($env)));
+            if (null !== $env && !\is_array($env)) {
+                throw new RuntimeException(sprintf('Invalid JSON env var "%s": array or null expected, %s given.', $name, \gettype($env)));
             }
 
             return $env;
@@ -163,7 +163,7 @@ class EnvVarProcessor implements EnvVarProcessorInterface
                 }
                 $value = $this->container->getParameter($match[1]);
                 if (!is_scalar($value)) {
-                    throw new RuntimeException(sprintf('Parameter "%s" found when resolving env var "%s" must be scalar, "%s" given.', $match[1], $name, gettype($value)));
+                    throw new RuntimeException(sprintf('Parameter "%s" found when resolving env var "%s" must be scalar, "%s" given.', $match[1], $name, \gettype($value)));
                 }
 
                 return $value;
diff --git a/src/Symfony/Component/DependencyInjection/Exception/ParameterNotFoundException.php b/src/Symfony/Component/DependencyInjection/Exception/ParameterNotFoundException.php
index 07066a9284..0560de00f7 100644
--- a/src/Symfony/Component/DependencyInjection/Exception/ParameterNotFoundException.php
+++ b/src/Symfony/Component/DependencyInjection/Exception/ParameterNotFoundException.php
@@ -58,7 +58,7 @@ class ParameterNotFoundException extends InvalidArgumentException implements Not
         }
 
         if ($this->alternatives) {
-            if (1 == count($this->alternatives)) {
+            if (1 == \count($this->alternatives)) {
                 $this->message .= ' Did you mean this: "';
             } else {
                 $this->message .= ' Did you mean one of these: "';
diff --git a/src/Symfony/Component/DependencyInjection/Exception/ServiceNotFoundException.php b/src/Symfony/Component/DependencyInjection/Exception/ServiceNotFoundException.php
index dabd9da4a4..d867ec6f86 100644
--- a/src/Symfony/Component/DependencyInjection/Exception/ServiceNotFoundException.php
+++ b/src/Symfony/Component/DependencyInjection/Exception/ServiceNotFoundException.php
@@ -35,7 +35,7 @@ class ServiceNotFoundException extends InvalidArgumentException implements NotFo
         }
 
         if ($alternatives) {
-            if (1 == count($alternatives)) {
+            if (1 == \count($alternatives)) {
                 $msg .= ' Did you mean this: "';
             } else {
                 $msg .= ' Did you mean one of these: "';
diff --git a/src/Symfony/Component/DependencyInjection/Extension/Extension.php b/src/Symfony/Component/DependencyInjection/Extension/Extension.php
index 7bb8ae3b5a..a21ce659a9 100644
--- a/src/Symfony/Component/DependencyInjection/Extension/Extension.php
+++ b/src/Symfony/Component/DependencyInjection/Extension/Extension.php
@@ -65,7 +65,7 @@ abstract class Extension implements ExtensionInterface, ConfigurationExtensionIn
      */
     public function getAlias()
     {
-        $className = get_class($this);
+        $className = \get_class($this);
         if ('Extension' != substr($className, -9)) {
             throw new BadMethodCallException('This extension does not follow the naming convention; you must overwrite the getAlias() method.');
         }
@@ -79,7 +79,7 @@ abstract class Extension implements ExtensionInterface, ConfigurationExtensionIn
      */
     public function getConfiguration(array $config, ContainerBuilder $container)
     {
-        $class = get_class($this);
+        $class = \get_class($this);
         $class = substr_replace($class, '\Configuration', strrpos($class, '\\'));
         $class = $container->getReflectionClass($class);
 
diff --git a/src/Symfony/Component/DependencyInjection/LazyProxy/Instantiator/RealServiceInstantiator.php b/src/Symfony/Component/DependencyInjection/LazyProxy/Instantiator/RealServiceInstantiator.php
index cad9320039..3b0b57ef0f 100644
--- a/src/Symfony/Component/DependencyInjection/LazyProxy/Instantiator/RealServiceInstantiator.php
+++ b/src/Symfony/Component/DependencyInjection/LazyProxy/Instantiator/RealServiceInstantiator.php
@@ -28,6 +28,6 @@ class RealServiceInstantiator implements InstantiatorInterface
      */
     public function instantiateProxy(ContainerInterface $container, Definition $definition, $id, $realInstantiator)
     {
-        return call_user_func($realInstantiator);
+        return \call_user_func($realInstantiator);
     }
 }
diff --git a/src/Symfony/Component/DependencyInjection/LazyProxy/ProxyHelper.php b/src/Symfony/Component/DependencyInjection/LazyProxy/ProxyHelper.php
index d258980d66..65e432d93c 100644
--- a/src/Symfony/Component/DependencyInjection/LazyProxy/ProxyHelper.php
+++ b/src/Symfony/Component/DependencyInjection/LazyProxy/ProxyHelper.php
@@ -31,7 +31,7 @@ class ProxyHelper
         if (!$type) {
             return;
         }
-        if (!is_string($type)) {
+        if (!\is_string($type)) {
             $name = $type->getName();
 
             if ($type->isBuiltin()) {
diff --git a/src/Symfony/Component/DependencyInjection/Loader/ClosureLoader.php b/src/Symfony/Component/DependencyInjection/Loader/ClosureLoader.php
index f8f2efe2e9..170b315477 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/ClosureLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/ClosureLoader.php
@@ -35,7 +35,7 @@ class ClosureLoader extends Loader
      */
     public function load($resource, $type = null)
     {
-        call_user_func($resource, $this->container);
+        \call_user_func($resource, $this->container);
     }
 
     /**
diff --git a/src/Symfony/Component/DependencyInjection/Loader/Configurator/AbstractConfigurator.php b/src/Symfony/Component/DependencyInjection/Loader/Configurator/AbstractConfigurator.php
index 73ca320e31..d11347aeab 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/Configurator/AbstractConfigurator.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/Configurator/AbstractConfigurator.php
@@ -28,10 +28,10 @@ abstract class AbstractConfigurator
     public function __call($method, $args)
     {
         if (method_exists($this, 'set'.$method)) {
-            return call_user_func_array(array($this, 'set'.$method), $args);
+            return \call_user_func_array(array($this, 'set'.$method), $args);
         }
 
-        throw new \BadMethodCallException(sprintf('Call to undefined method %s::%s()', get_class($this), $method));
+        throw new \BadMethodCallException(sprintf('Call to undefined method %s::%s()', \get_class($this), $method));
     }
 
     /**
@@ -44,7 +44,7 @@ abstract class AbstractConfigurator
      */
     public static function processValue($value, $allowServices = false)
     {
-        if (is_array($value)) {
+        if (\is_array($value)) {
             foreach ($value as $k => $v) {
                 $value[$k] = static::processValue($v, $allowServices);
             }
@@ -82,6 +82,6 @@ abstract class AbstractConfigurator
                 }
         }
 
-        throw new InvalidArgumentException(sprintf('Cannot use values of type "%s" in service configuration files.', is_object($value) ? get_class($value) : gettype($value)));
+        throw new InvalidArgumentException(sprintf('Cannot use values of type "%s" in service configuration files.', \is_object($value) ? \get_class($value) : \gettype($value)));
     }
 }
diff --git a/src/Symfony/Component/DependencyInjection/Loader/Configurator/ContainerConfigurator.php b/src/Symfony/Component/DependencyInjection/Loader/Configurator/ContainerConfigurator.php
index f002ee2f38..f1593e4f69 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/Configurator/ContainerConfigurator.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/Configurator/ContainerConfigurator.php
@@ -62,7 +62,7 @@ class ContainerConfigurator extends AbstractConfigurator
 
     final public function import(string $resource, string $type = null, bool $ignoreErrors = false)
     {
-        $this->loader->setCurrentDir(dirname($this->path));
+        $this->loader->setCurrentDir(\dirname($this->path));
         $this->loader->import($resource, $type, $ignoreErrors, $this->file);
     }
 
diff --git a/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/FactoryTrait.php b/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/FactoryTrait.php
index 12e8859ca1..0d50fb747f 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/FactoryTrait.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/FactoryTrait.php
@@ -24,7 +24,7 @@ trait FactoryTrait
      */
     final public function factory($factory)
     {
-        if (is_string($factory) && 1 === substr_count($factory, ':')) {
+        if (\is_string($factory) && 1 === substr_count($factory, ':')) {
             $factoryParts = explode(':', $factory);
 
             throw new InvalidArgumentException(sprintf('Invalid factory "%s": the `service:method` notation is not available when using PHP-based DI configuration. Use "[ref(\'%s\'), \'%s\']" instead.', $factory, $factoryParts[0], $factoryParts[1]));
diff --git a/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/TagTrait.php b/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/TagTrait.php
index aeb8b047d4..c165b6503e 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/TagTrait.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/Configurator/Traits/TagTrait.php
@@ -25,7 +25,7 @@ trait TagTrait
      */
     final public function tag($name, array $attributes = array())
     {
-        if (!is_string($name) || '' === $name) {
+        if (!\is_string($name) || '' === $name) {
             throw new InvalidArgumentException(sprintf('The tag name for service "%s" must be a non-empty string.', $this->id));
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Loader/DirectoryLoader.php b/src/Symfony/Component/DependencyInjection/Loader/DirectoryLoader.php
index 769f1026e8..a57cac3b5e 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/DirectoryLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/DirectoryLoader.php
@@ -49,6 +49,6 @@ class DirectoryLoader extends FileLoader
             return true;
         }
 
-        return null === $type && is_string($resource) && '/' === substr($resource, -1);
+        return null === $type && \is_string($resource) && '/' === substr($resource, -1);
     }
 }
diff --git a/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php
index b193354a6e..13ae265fb6 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/FileLoader.php
@@ -93,7 +93,7 @@ abstract class FileLoader extends BaseFileLoader
     {
         if ($this->isLoadingInstanceof) {
             if (!$definition instanceof ChildDefinition) {
-                throw new InvalidArgumentException(sprintf('Invalid type definition "%s": ChildDefinition expected, "%s" given.', $id, get_class($definition)));
+                throw new InvalidArgumentException(sprintf('Invalid type definition "%s": ChildDefinition expected, "%s" given.', $id, \get_class($definition)));
             }
             $this->instanceof[$id] = $definition;
         } else {
@@ -125,7 +125,7 @@ abstract class FileLoader extends BaseFileLoader
         $prefixLen = null;
         foreach ($this->glob($pattern, true, $resource) as $path => $info) {
             if (null === $prefixLen) {
-                $prefixLen = strlen($resource->getPrefix());
+                $prefixLen = \strlen($resource->getPrefix());
 
                 if ($excludePrefix && 0 !== strpos($excludePrefix, $resource->getPrefix())) {
                     throw new InvalidArgumentException(sprintf('Invalid "exclude" pattern when importing classes for "%s": make sure your "exclude" pattern (%s) is a subset of the "resource" pattern (%s)', $namespace, $excludePattern, $pattern));
@@ -139,7 +139,7 @@ abstract class FileLoader extends BaseFileLoader
             if (!preg_match($extRegexp, $path, $m) || !$info->isReadable()) {
                 continue;
             }
-            $class = $namespace.ltrim(str_replace('/', '\\', substr($path, $prefixLen, -strlen($m[0]))), '\\');
+            $class = $namespace.ltrim(str_replace('/', '\\', substr($path, $prefixLen, -\strlen($m[0]))), '\\');
 
             if (!preg_match('/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+(?:\\\\[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*+)*+$/', $class)) {
                 continue;
diff --git a/src/Symfony/Component/DependencyInjection/Loader/IniFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/IniFileLoader.php
index 6cc9a1acaf..ed3709104a 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/IniFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/IniFileLoader.php
@@ -39,7 +39,7 @@ class IniFileLoader extends FileLoader
         // real raw parsing
         $result = parse_ini_file($path, true, INI_SCANNER_RAW);
 
-        if (isset($result['parameters']) && is_array($result['parameters'])) {
+        if (isset($result['parameters']) && \is_array($result['parameters'])) {
             foreach ($result['parameters'] as $key => $value) {
                 $this->container->setParameter($key, $this->phpize($value));
             }
@@ -51,7 +51,7 @@ class IniFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        if (!is_string($resource)) {
+        if (!\is_string($resource)) {
             return false;
         }
 
@@ -74,15 +74,15 @@ class IniFileLoader extends FileLoader
         $lowercaseValue = strtolower($value);
 
         switch (true) {
-            case defined($value):
-                return constant($value);
+            case \defined($value):
+                return \constant($value);
             case 'yes' === $lowercaseValue || 'on' === $lowercaseValue:
                 return true;
             case 'no' === $lowercaseValue || 'off' === $lowercaseValue || 'none' === $lowercaseValue:
                 return false;
             case isset($value[1]) && (
-                ("'" === $value[0] && "'" === $value[strlen($value) - 1]) ||
-                ('"' === $value[0] && '"' === $value[strlen($value) - 1])
+                ("'" === $value[0] && "'" === $value[\strlen($value) - 1]) ||
+                ('"' === $value[0] && '"' === $value[\strlen($value) - 1])
             ):
                 // quoted string
                 return substr($value, 1, -1);
diff --git a/src/Symfony/Component/DependencyInjection/Loader/PhpFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/PhpFileLoader.php
index 0225338454..033798f681 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/PhpFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/PhpFileLoader.php
@@ -33,7 +33,7 @@ class PhpFileLoader extends FileLoader
         $loader = $this;
 
         $path = $this->locator->locate($resource);
-        $this->setCurrentDir(dirname($path));
+        $this->setCurrentDir(\dirname($path));
         $this->container->fileExists($path);
 
         // the closure forbids access to the private scope in the included file
@@ -53,7 +53,7 @@ class PhpFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        if (!is_string($resource)) {
+        if (!\is_string($resource)) {
             return false;
         }
 
diff --git a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
index 584e3992c9..05b92eca77 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
@@ -74,7 +74,7 @@ class XmlFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        if (!is_string($resource)) {
+        if (!\is_string($resource)) {
             return false;
         }
 
@@ -113,7 +113,7 @@ class XmlFileLoader extends FileLoader
             return;
         }
 
-        $defaultDirectory = dirname($file);
+        $defaultDirectory = \dirname($file);
         foreach ($imports as $import) {
             $this->setCurrentDir($defaultDirectory);
             $this->import($import->getAttribute('resource'), XmlUtils::phpize($import->getAttribute('type')) ?: null, (bool) XmlUtils::phpize($import->getAttribute('ignore-errors')), $file);
@@ -134,7 +134,7 @@ class XmlFileLoader extends FileLoader
         if (false === $services = $xpath->query('//container:services/container:service|//container:services/container:prototype')) {
             return;
         }
-        $this->setCurrentDir(dirname($file));
+        $this->setCurrentDir(\dirname($file));
 
         $this->instanceof = array();
         $this->isLoadingInstanceof = true;
@@ -149,7 +149,7 @@ class XmlFileLoader extends FileLoader
                 if ('prototype' === $service->tagName) {
                     $excludes = array_column($this->getChildren($service, 'exclude'), 'nodeValue');
                     if ($service->hasAttribute('exclude')) {
-                        if (count($excludes) > 0) {
+                        if (\count($excludes) > 0) {
                             throw new InvalidArgumentException('You cannot use both the attribute "exclude" and <exclude> tags at the same time.');
                         }
                         $excludes = array($service->getAttribute('exclude'));
@@ -545,7 +545,7 @@ class XmlFileLoader extends FileLoader
                     $arguments[$key] = $arg->nodeValue;
                     break;
                 case 'constant':
-                    $arguments[$key] = constant(trim($arg->nodeValue));
+                    $arguments[$key] = \constant(trim($arg->nodeValue));
                     break;
                 default:
                     $arguments[$key] = XmlUtils::phpize($arg->nodeValue);
@@ -590,7 +590,7 @@ class XmlFileLoader extends FileLoader
 
         if ($element = $dom->documentElement->getAttributeNS('http://www.w3.org/2001/XMLSchema-instance', 'schemaLocation')) {
             $items = preg_split('/\s+/', $element);
-            for ($i = 0, $nb = count($items); $i < $nb; $i += 2) {
+            for ($i = 0, $nb = \count($items); $i < $nb; $i += 2) {
                 if (!$this->container->hasExtension($items[$i])) {
                     continue;
                 }
@@ -599,7 +599,7 @@ class XmlFileLoader extends FileLoader
                     $path = str_replace($extension->getNamespace(), str_replace('\\', '/', $extension->getXsdValidationBasePath()).'/', $items[$i + 1]);
 
                     if (!is_file($path)) {
-                        throw new RuntimeException(sprintf('Extension "%s" references a non-existent XSD file "%s"', get_class($extension), $path));
+                        throw new RuntimeException(sprintf('Extension "%s" references a non-existent XSD file "%s"', \get_class($extension), $path));
                     }
 
                     $schemaLocations[$items[$i]] = $path;
@@ -662,7 +662,7 @@ EOF
     private function validateAlias(\DOMElement $alias, $file)
     {
         foreach ($alias->attributes as $name => $node) {
-            if (!in_array($name, array('alias', 'id', 'public'))) {
+            if (!\in_array($name, array('alias', 'id', 'public'))) {
                 throw new InvalidArgumentException(sprintf('Invalid attribute "%s" defined for alias "%s" in "%s".', $name, $alias->getAttribute('id'), $file));
             }
         }
@@ -716,7 +716,7 @@ EOF
             }
 
             $values = static::convertDomElementToArray($node);
-            if (!is_array($values)) {
+            if (!\is_array($values)) {
                 $values = array();
             }
 
diff --git a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
index 79b377f0bd..14341f1a69 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
@@ -129,7 +129,7 @@ class YamlFileLoader extends FileLoader
 
         // parameters
         if (isset($content['parameters'])) {
-            if (!is_array($content['parameters'])) {
+            if (!\is_array($content['parameters'])) {
                 throw new InvalidArgumentException(sprintf('The "parameters" key should contain an array in %s. Check your YAML syntax.', $path));
             }
 
@@ -144,7 +144,7 @@ class YamlFileLoader extends FileLoader
         // services
         $this->anonymousServicesCount = 0;
         $this->anonymousServicesSuffix = ContainerBuilder::hash($path);
-        $this->setCurrentDir(dirname($path));
+        $this->setCurrentDir(\dirname($path));
         try {
             $this->parseDefinitions($content, $path);
         } finally {
@@ -157,15 +157,15 @@ class YamlFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        if (!is_string($resource)) {
+        if (!\is_string($resource)) {
             return false;
         }
 
-        if (null === $type && in_array(pathinfo($resource, PATHINFO_EXTENSION), array('yaml', 'yml'), true)) {
+        if (null === $type && \in_array(pathinfo($resource, PATHINFO_EXTENSION), array('yaml', 'yml'), true)) {
             return true;
         }
 
-        return in_array($type, array('yaml', 'yml'), true);
+        return \in_array($type, array('yaml', 'yml'), true);
     }
 
     private function parseImports(array $content, string $file)
@@ -174,13 +174,13 @@ class YamlFileLoader extends FileLoader
             return;
         }
 
-        if (!is_array($content['imports'])) {
+        if (!\is_array($content['imports'])) {
             throw new InvalidArgumentException(sprintf('The "imports" key should contain an array in %s. Check your YAML syntax.', $file));
         }
 
-        $defaultDirectory = dirname($file);
+        $defaultDirectory = \dirname($file);
         foreach ($content['imports'] as $import) {
-            if (!is_array($import)) {
+            if (!\is_array($import)) {
                 $import = array('resource' => $import);
             }
             if (!isset($import['resource'])) {
@@ -198,7 +198,7 @@ class YamlFileLoader extends FileLoader
             return;
         }
 
-        if (!is_array($content['services'])) {
+        if (!\is_array($content['services'])) {
             throw new InvalidArgumentException(sprintf('The "services" key should contain an array in %s. Check your YAML syntax.', $file));
         }
 
@@ -206,16 +206,16 @@ class YamlFileLoader extends FileLoader
             $instanceof = $content['services']['_instanceof'];
             unset($content['services']['_instanceof']);
 
-            if (!is_array($instanceof)) {
-                throw new InvalidArgumentException(sprintf('Service "_instanceof" key must be an array, "%s" given in "%s".', gettype($instanceof), $file));
+            if (!\is_array($instanceof)) {
+                throw new InvalidArgumentException(sprintf('Service "_instanceof" key must be an array, "%s" given in "%s".', \gettype($instanceof), $file));
             }
             $this->instanceof = array();
             $this->isLoadingInstanceof = true;
             foreach ($instanceof as $id => $service) {
-                if (!$service || !is_array($service)) {
+                if (!$service || !\is_array($service)) {
                     throw new InvalidArgumentException(sprintf('Type definition "%s" must be a non-empty array within "_instanceof" in %s. Check your YAML syntax.', $id, $file));
                 }
-                if (is_string($service) && 0 === strpos($service, '@')) {
+                if (\is_string($service) && 0 === strpos($service, '@')) {
                     throw new InvalidArgumentException(sprintf('Type definition "%s" cannot be an alias within "_instanceof" in %s. Check your YAML syntax.', $id, $file));
                 }
                 $this->parseDefinition($id, $service, $file, array());
@@ -240,8 +240,8 @@ class YamlFileLoader extends FileLoader
         $defaults = $content['services']['_defaults'];
         unset($content['services']['_defaults']);
 
-        if (!is_array($defaults)) {
-            throw new InvalidArgumentException(sprintf('Service "_defaults" key must be an array, "%s" given in "%s".', gettype($defaults), $file));
+        if (!\is_array($defaults)) {
+            throw new InvalidArgumentException(sprintf('Service "_defaults" key must be an array, "%s" given in "%s".', \gettype($defaults), $file));
         }
 
         foreach ($defaults as $key => $default) {
@@ -251,12 +251,12 @@ class YamlFileLoader extends FileLoader
         }
 
         if (isset($defaults['tags'])) {
-            if (!is_array($tags = $defaults['tags'])) {
+            if (!\is_array($tags = $defaults['tags'])) {
                 throw new InvalidArgumentException(sprintf('Parameter "tags" in "_defaults" must be an array in %s. Check your YAML syntax.', $file));
             }
 
             foreach ($tags as $tag) {
-                if (!is_array($tag)) {
+                if (!\is_array($tag)) {
                     $tag = array('name' => $tag);
                 }
 
@@ -266,7 +266,7 @@ class YamlFileLoader extends FileLoader
                 $name = $tag['name'];
                 unset($tag['name']);
 
-                if (!is_string($name) || '' === $name) {
+                if (!\is_string($name) || '' === $name) {
                     throw new InvalidArgumentException(sprintf('The tag name in "_defaults" must be a non-empty string in %s.', $file));
                 }
 
@@ -279,7 +279,7 @@ class YamlFileLoader extends FileLoader
         }
 
         if (isset($defaults['bind'])) {
-            if (!is_array($defaults['bind'])) {
+            if (!\is_array($defaults['bind'])) {
                 throw new InvalidArgumentException(sprintf('Parameter "bind" in "_defaults" must be an array in %s. Check your YAML syntax.', $file));
             }
 
@@ -292,7 +292,7 @@ class YamlFileLoader extends FileLoader
     private function isUsingShortSyntax(array $service): bool
     {
         foreach ($service as $key => $value) {
-            if (is_string($key) && ('' === $key || '$' !== $key[0])) {
+            if (\is_string($key) && ('' === $key || '$' !== $key[0])) {
                 return false;
             }
         }
@@ -316,7 +316,7 @@ class YamlFileLoader extends FileLoader
             throw new InvalidArgumentException(sprintf('Service names that start with an underscore are reserved. Rename the "%s" service or define it in XML instead.', $id));
         }
 
-        if (is_string($service) && 0 === strpos($service, '@')) {
+        if (\is_string($service) && 0 === strpos($service, '@')) {
             $this->container->setAlias($id, $alias = new Alias(substr($service, 1)));
             if (isset($defaults['public'])) {
                 $alias->setPublic($defaults['public']);
@@ -325,7 +325,7 @@ class YamlFileLoader extends FileLoader
             return;
         }
 
-        if (is_array($service) && $this->isUsingShortSyntax($service)) {
+        if (\is_array($service) && $this->isUsingShortSyntax($service)) {
             $service = array('arguments' => $service);
         }
 
@@ -333,8 +333,8 @@ class YamlFileLoader extends FileLoader
             $service = array();
         }
 
-        if (!is_array($service)) {
-            throw new InvalidArgumentException(sprintf('A service definition must be an array or a string starting with "@" but %s found for service "%s" in %s. Check your YAML syntax.', gettype($service), $id, $file));
+        if (!\is_array($service)) {
+            throw new InvalidArgumentException(sprintf('A service definition must be an array or a string starting with "@" but %s found for service "%s" in %s. Check your YAML syntax.', \gettype($service), $id, $file));
         }
 
         $this->checkDefinition($id, $service, $file);
@@ -348,7 +348,7 @@ class YamlFileLoader extends FileLoader
             }
 
             foreach ($service as $key => $value) {
-                if (!in_array($key, array('alias', 'public'))) {
+                if (!\in_array($key, array('alias', 'public'))) {
                     throw new InvalidArgumentException(sprintf('The configuration key "%s" is unsupported for the service "%s" which is defined as an alias in "%s". Allowed configuration keys for service aliases are "alias" and "public".', $key, $id, $file));
                 }
             }
@@ -446,7 +446,7 @@ class YamlFileLoader extends FileLoader
         }
 
         if (isset($service['calls'])) {
-            if (!is_array($service['calls'])) {
+            if (!\is_array($service['calls'])) {
                 throw new InvalidArgumentException(sprintf('Parameter "calls" must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
             }
 
@@ -459,7 +459,7 @@ class YamlFileLoader extends FileLoader
                     $args = isset($call[1]) ? $this->resolveServices($call[1], $file) : array();
                 }
 
-                if (!is_array($args)) {
+                if (!\is_array($args)) {
                     throw new InvalidArgumentException(sprintf('The second parameter for function call "%s" must be an array of its arguments for service "%s" in %s. Check your YAML syntax.', $method, $id, $file));
                 }
                 $definition->addMethodCall($method, $args);
@@ -467,7 +467,7 @@ class YamlFileLoader extends FileLoader
         }
 
         $tags = isset($service['tags']) ? $service['tags'] : array();
-        if (!is_array($tags)) {
+        if (!\is_array($tags)) {
             throw new InvalidArgumentException(sprintf('Parameter "tags" must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
         }
 
@@ -476,7 +476,7 @@ class YamlFileLoader extends FileLoader
         }
 
         foreach ($tags as $tag) {
-            if (!is_array($tag)) {
+            if (!\is_array($tag)) {
                 $tag = array('name' => $tag);
             }
 
@@ -486,7 +486,7 @@ class YamlFileLoader extends FileLoader
             $name = $tag['name'];
             unset($tag['name']);
 
-            if (!is_string($name) || '' === $name) {
+            if (!\is_string($name) || '' === $name) {
                 throw new InvalidArgumentException(sprintf('The tag name for service "%s" in %s must be a non-empty string.', $id, $file));
             }
 
@@ -518,7 +518,7 @@ class YamlFileLoader extends FileLoader
             $bindings = isset($defaults['bind']) ? unserialize(serialize($defaults['bind'])) : array();
 
             if (isset($service['bind'])) {
-                if (!is_array($service['bind'])) {
+                if (!\is_array($service['bind'])) {
                     throw new InvalidArgumentException(sprintf('Parameter "bind" must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
                 }
 
@@ -541,7 +541,7 @@ class YamlFileLoader extends FileLoader
         }
 
         if (array_key_exists('resource', $service)) {
-            if (!is_string($service['resource'])) {
+            if (!\is_string($service['resource'])) {
                 throw new InvalidArgumentException(sprintf('A "resource" attribute must be of type string for service "%s" in %s. Check your YAML syntax.', $id, $file));
             }
             $exclude = isset($service['exclude']) ? $service['exclude'] : null;
@@ -566,7 +566,7 @@ class YamlFileLoader extends FileLoader
      */
     private function parseCallable($callable, $parameter, $id, $file)
     {
-        if (is_string($callable)) {
+        if (\is_string($callable)) {
             if ('' !== $callable && '@' === $callable[0]) {
                 throw new InvalidArgumentException(sprintf('The value of the "%s" option for the "%s" service must be the id of the service without the "@" prefix (replace "%s" with "%s").', $parameter, $id, $callable, substr($callable, 1)));
             }
@@ -580,7 +580,7 @@ class YamlFileLoader extends FileLoader
             return $callable;
         }
 
-        if (is_array($callable)) {
+        if (\is_array($callable)) {
             if (isset($callable[0]) && isset($callable[1])) {
                 return array($this->resolveServices($callable[0], $file), $callable[1]);
             }
@@ -647,12 +647,12 @@ class YamlFileLoader extends FileLoader
             return $content;
         }
 
-        if (!is_array($content)) {
+        if (!\is_array($content)) {
             throw new InvalidArgumentException(sprintf('The service file "%s" is not valid. It should contain an array. Check your YAML syntax.', $file));
         }
 
         foreach ($content as $namespace => $data) {
-            if (in_array($namespace, array('imports', 'parameters', 'services'))) {
+            if (\in_array($namespace, array('imports', 'parameters', 'services'))) {
                 continue;
             }
 
@@ -685,7 +685,7 @@ class YamlFileLoader extends FileLoader
         if ($value instanceof TaggedValue) {
             $argument = $value->getValue();
             if ('iterator' === $value->getTag()) {
-                if (!is_array($argument)) {
+                if (!\is_array($argument)) {
                     throw new InvalidArgumentException(sprintf('"!iterator" tag only accepts sequences in "%s".', $file));
                 }
                 $argument = $this->resolveServices($argument, $file, $isParameter);
@@ -696,7 +696,7 @@ class YamlFileLoader extends FileLoader
                 }
             }
             if ('service_locator' === $value->getTag()) {
-                if (!is_array($argument)) {
+                if (!\is_array($argument)) {
                     throw new InvalidArgumentException(sprintf('"!service_locator" tag only accepts maps in "%s".', $file));
                 }
                 $argument = $this->resolveServices($argument, $file, $isParameter);
@@ -707,7 +707,7 @@ class YamlFileLoader extends FileLoader
                 }
             }
             if ('tagged' === $value->getTag()) {
-                if (!is_string($argument) || !$argument) {
+                if (!\is_string($argument) || !$argument) {
                     throw new InvalidArgumentException(sprintf('"!tagged" tag only accepts non empty string in "%s".', $file));
                 }
 
@@ -741,17 +741,17 @@ class YamlFileLoader extends FileLoader
             throw new InvalidArgumentException(sprintf('Unsupported tag "!%s".', $value->getTag()));
         }
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             foreach ($value as $k => $v) {
                 $value[$k] = $this->resolveServices($v, $file, $isParameter);
             }
-        } elseif (is_string($value) && 0 === strpos($value, '@=')) {
+        } elseif (\is_string($value) && 0 === strpos($value, '@=')) {
             if (!class_exists(Expression::class)) {
                 throw new \LogicException(sprintf('The "@=" expression syntax cannot be used without the ExpressionLanguage component. Try running "composer require symfony/expression-language".'));
             }
 
             return new Expression(substr($value, 2));
-        } elseif (is_string($value) && 0 === strpos($value, '@')) {
+        } elseif (\is_string($value) && 0 === strpos($value, '@')) {
             if (0 === strpos($value, '@@')) {
                 $value = substr($value, 1);
                 $invalidBehavior = null;
@@ -780,11 +780,11 @@ class YamlFileLoader extends FileLoader
     private function loadFromExtensions(array $content)
     {
         foreach ($content as $namespace => $values) {
-            if (in_array($namespace, array('imports', 'parameters', 'services'))) {
+            if (\in_array($namespace, array('imports', 'parameters', 'services'))) {
                 continue;
             }
 
-            if (!is_array($values) && null !== $values) {
+            if (!\is_array($values) && null !== $values) {
                 $values = array();
             }
 
diff --git a/src/Symfony/Component/DependencyInjection/ParameterBag/EnvPlaceholderParameterBag.php b/src/Symfony/Component/DependencyInjection/ParameterBag/EnvPlaceholderParameterBag.php
index 20fc77c8b4..8c91d1de39 100644
--- a/src/Symfony/Component/DependencyInjection/ParameterBag/EnvPlaceholderParameterBag.php
+++ b/src/Symfony/Component/DependencyInjection/ParameterBag/EnvPlaceholderParameterBag.php
@@ -50,7 +50,7 @@ class EnvPlaceholderParameterBag extends ParameterBag
                 $defaultValue = parent::get($name);
 
                 if (null !== $defaultValue && !is_scalar($defaultValue)) {
-                    throw new RuntimeException(sprintf('The default value of an env() parameter must be scalar or null, but "%s" given to "%s".', gettype($defaultValue), $name));
+                    throw new RuntimeException(sprintf('The default value of an env() parameter must be scalar or null, but "%s" given to "%s".', \gettype($defaultValue), $name));
                 }
             }
 
@@ -149,7 +149,7 @@ class EnvPlaceholderParameterBag extends ParameterBag
             if (is_numeric($default = $this->parameters[$name])) {
                 $this->parameters[$name] = (string) $default;
             } elseif (null !== $default && !is_scalar($default)) {
-                throw new RuntimeException(sprintf('The default value of env parameter "%s" must be scalar or null, %s given.', $env, gettype($default)));
+                throw new RuntimeException(sprintf('The default value of env parameter "%s" must be scalar or null, %s given.', $env, \gettype($default)));
             }
         }
     }
diff --git a/src/Symfony/Component/DependencyInjection/ParameterBag/ParameterBag.php b/src/Symfony/Component/DependencyInjection/ParameterBag/ParameterBag.php
index dc5a4be292..ccf1371b31 100644
--- a/src/Symfony/Component/DependencyInjection/ParameterBag/ParameterBag.php
+++ b/src/Symfony/Component/DependencyInjection/ParameterBag/ParameterBag.php
@@ -76,18 +76,18 @@ class ParameterBag implements ParameterBagInterface
             $alternatives = array();
             foreach ($this->parameters as $key => $parameterValue) {
                 $lev = levenshtein($name, $key);
-                if ($lev <= strlen($name) / 3 || false !== strpos($key, $name)) {
+                if ($lev <= \strlen($name) / 3 || false !== strpos($key, $name)) {
                     $alternatives[] = $key;
                 }
             }
 
             $nonNestedAlternative = null;
-            if (!count($alternatives) && false !== strpos($name, '.')) {
+            if (!\count($alternatives) && false !== strpos($name, '.')) {
                 $namePartsLength = array_map('strlen', explode('.', $name));
                 $key = substr($name, 0, -1 * (1 + array_pop($namePartsLength)));
-                while (count($namePartsLength)) {
+                while (\count($namePartsLength)) {
                     if ($this->has($key)) {
-                        if (is_array($this->get($key))) {
+                        if (\is_array($this->get($key))) {
                             $nonNestedAlternative = $key;
                         }
                         break;
@@ -229,8 +229,8 @@ class ParameterBag implements ParameterBagInterface
 
             $resolved = $this->get($key);
 
-            if (!is_string($resolved) && !is_numeric($resolved)) {
-                throw new RuntimeException(sprintf('A string value must be composed of strings and/or numbers, but found parameter "%s" of type %s inside string value "%s".', $key, gettype($resolved), $value));
+            if (!\is_string($resolved) && !is_numeric($resolved)) {
+                throw new RuntimeException(sprintf('A string value must be composed of strings and/or numbers, but found parameter "%s" of type %s inside string value "%s".', $key, \gettype($resolved), $value));
             }
 
             $resolved = (string) $resolved;
@@ -250,11 +250,11 @@ class ParameterBag implements ParameterBagInterface
      */
     public function escapeValue($value)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             return str_replace('%', '%%', $value);
         }
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             $result = array();
             foreach ($value as $k => $v) {
                 $result[$k] = $this->escapeValue($v);
@@ -271,11 +271,11 @@ class ParameterBag implements ParameterBagInterface
      */
     public function unescapeValue($value)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             return str_replace('%%', '%', $value);
         }
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             $result = array();
             foreach ($value as $k => $v) {
                 $result[$k] = $this->unescapeValue($v);
diff --git a/src/Symfony/Component/DependencyInjection/ServiceLocator.php b/src/Symfony/Component/DependencyInjection/ServiceLocator.php
index 1078695cde..5ec14147d1 100644
--- a/src/Symfony/Component/DependencyInjection/ServiceLocator.php
+++ b/src/Symfony/Component/DependencyInjection/ServiceLocator.php
@@ -54,7 +54,7 @@ class ServiceLocator implements PsrContainerInterface
 
         if (isset($this->loading[$id])) {
             $ids = array_values($this->loading);
-            $ids = array_slice($this->loading, array_search($id, $ids));
+            $ids = \array_slice($this->loading, array_search($id, $ids));
             $ids[] = $id;
 
             throw new ServiceCircularReferenceException($id, $ids);
@@ -108,7 +108,7 @@ class ServiceLocator implements PsrContainerInterface
         }
 
         $class = debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT | DEBUG_BACKTRACE_IGNORE_ARGS, 3);
-        $class = isset($class[2]['object']) ? get_class($class[2]['object']) : null;
+        $class = isset($class[2]['object']) ? \get_class($class[2]['object']) : null;
         $externalId = $this->externalId ?: $class;
 
         $msg = sprintf('Service "%s" not found: ', $id);
@@ -153,7 +153,7 @@ class ServiceLocator implements PsrContainerInterface
             if (!$alternatives = array_keys($this->factories)) {
                 return 'is empty...';
             }
-            $format = sprintf('only knows about the %s service%s.', $format, 1 < count($alternatives) ? 's' : '');
+            $format = sprintf('only knows about the %s service%s.', $format, 1 < \count($alternatives) ? 's' : '');
         }
         $last = array_pop($alternatives);
 
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Argument/RewindableGeneratorTest.php b/src/Symfony/Component/DependencyInjection/Tests/Argument/RewindableGeneratorTest.php
index 1415869a4f..31e3f11fec 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Argument/RewindableGeneratorTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Argument/RewindableGeneratorTest.php
@@ -46,7 +46,7 @@ class RewindableGeneratorTest extends TestCase
         $this->assertSame(0, $called, 'Count callback is called lazily');
         $this->assertCount(3, $generator);
 
-        count($generator);
+        \count($generator);
 
         $this->assertSame(1, $called, 'Count callback is called only once');
     }
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Compiler/ResolveChildDefinitionsPassTest.php b/src/Symfony/Component/DependencyInjection/Tests/Compiler/ResolveChildDefinitionsPassTest.php
index e633f84319..cf011b43e3 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Compiler/ResolveChildDefinitionsPassTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Compiler/ResolveChildDefinitionsPassTest.php
@@ -259,23 +259,23 @@ class ResolveChildDefinitionsPassTest extends TestCase
         $this->process($container);
 
         $configurator = $container->getDefinition('sibling')->getConfigurator();
-        $this->assertSame('Symfony\Component\DependencyInjection\Definition', get_class($configurator));
+        $this->assertSame('Symfony\Component\DependencyInjection\Definition', \get_class($configurator));
         $this->assertSame('parentClass', $configurator->getClass());
 
         $factory = $container->getDefinition('sibling')->getFactory();
-        $this->assertSame('Symfony\Component\DependencyInjection\Definition', get_class($factory[0]));
+        $this->assertSame('Symfony\Component\DependencyInjection\Definition', \get_class($factory[0]));
         $this->assertSame('parentClass', $factory[0]->getClass());
 
         $argument = $container->getDefinition('sibling')->getArgument(0);
-        $this->assertSame('Symfony\Component\DependencyInjection\Definition', get_class($argument));
+        $this->assertSame('Symfony\Component\DependencyInjection\Definition', \get_class($argument));
         $this->assertSame('parentClass', $argument->getClass());
 
         $properties = $container->getDefinition('sibling')->getProperties();
-        $this->assertSame('Symfony\Component\DependencyInjection\Definition', get_class($properties['prop']));
+        $this->assertSame('Symfony\Component\DependencyInjection\Definition', \get_class($properties['prop']));
         $this->assertSame('parentClass', $properties['prop']->getClass());
 
         $methodCalls = $container->getDefinition('sibling')->getMethodCalls();
-        $this->assertSame('Symfony\Component\DependencyInjection\Definition', get_class($methodCalls[0][1][0]));
+        $this->assertSame('Symfony\Component\DependencyInjection\Definition', \get_class($methodCalls[0][1][0]));
         $this->assertSame('parentClass', $methodCalls[0][1][0]->getClass());
     }
 
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Compiler/ValidateEnvPlaceholdersPassTest.php b/src/Symfony/Component/DependencyInjection/Tests/Compiler/ValidateEnvPlaceholdersPassTest.php
index af92cf92d6..32a5bb1ab6 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Compiler/ValidateEnvPlaceholdersPassTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Compiler/ValidateEnvPlaceholdersPassTest.php
@@ -286,7 +286,7 @@ class EnvConfiguration implements ConfigurationInterface
                 ->booleanNode('bool_node')->end()
                 ->arrayNode('array_node')
                     ->beforeNormalization()
-                        ->ifTrue(function ($value) { return !is_array($value); })
+                        ->ifTrue(function ($value) { return !\is_array($value); })
                         ->then(function ($value) { return array('child_node' => $value); })
                     ->end()
                     ->beforeNormalization()
diff --git a/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php b/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
index b33c753ead..0f2e3bb370 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/ContainerBuilderTest.php
@@ -333,7 +333,7 @@ class ContainerBuilderTest extends TestCase
         $builder->addCompilerPass($pass2 = $this->getMockBuilder('Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface')->getMock(), PassConfig::TYPE_BEFORE_OPTIMIZATION, 10);
 
         $passes = $builder->getCompiler()->getPassConfig()->getPasses();
-        $this->assertCount(count($passes) - 2, $defaultPasses);
+        $this->assertCount(\count($passes) - 2, $defaultPasses);
         // Pass 1 is executed later
         $this->assertTrue(array_search($pass1, $passes, true) > array_search($pass2, $passes, true));
     }
@@ -358,7 +358,7 @@ class ContainerBuilderTest extends TestCase
         $foo1 = $builder->get('foo1');
 
         $this->assertSame($foo1, $builder->get('foo1'), 'The same proxy is retrieved on multiple subsequent calls');
-        $this->assertSame('Bar\FooClass', get_class($foo1));
+        $this->assertSame('Bar\FooClass', \get_class($foo1));
     }
 
     public function testCreateServiceClass()
@@ -972,7 +972,7 @@ class ContainerBuilderTest extends TestCase
         $A = new ComposerResource();
         $a = new FileResource(__DIR__.'/Fixtures/xml/services1.xml');
         $b = new FileResource(__DIR__.'/Fixtures/xml/services2.xml');
-        $c = new DirectoryResource($dir = dirname($b));
+        $c = new DirectoryResource($dir = \dirname($b));
 
         $this->assertTrue($container->fileExists((string) $a) && $container->fileExists((string) $b) && $container->fileExists($dir));
 
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Dumper/PhpDumperTest.php b/src/Symfony/Component/DependencyInjection/Tests/Dumper/PhpDumperTest.php
index 684362081e..5cb09900ea 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Dumper/PhpDumperTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Dumper/PhpDumperTest.php
@@ -97,10 +97,10 @@ class PhpDumperTest extends TestCase
 
         $container = new ContainerBuilder();
         $container->setDefinition('test', $definition);
-        $container->setParameter('foo', 'wiz'.dirname(__DIR__));
+        $container->setParameter('foo', 'wiz'.\dirname(__DIR__));
         $container->setParameter('bar', __DIR__);
         $container->setParameter('baz', '%bar%/PhpDumperTest.php');
-        $container->setParameter('buz', dirname(dirname(__DIR__)));
+        $container->setParameter('buz', \dirname(\dirname(__DIR__)));
         $container->compile();
 
         $dumper = new PhpDumper($container);
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php b/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php
index 27a3d8ca94..205b42cd32 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Loader/XmlFileLoaderTest.php
@@ -446,7 +446,7 @@ class XmlFileLoaderTest extends TestCase
 
     public function testExtensionInPhar()
     {
-        if (extension_loaded('suhosin') && false === strpos(ini_get('suhosin.executor.include.whitelist'), 'phar')) {
+        if (\extension_loaded('suhosin') && false === strpos(ini_get('suhosin.executor.include.whitelist'), 'phar')) {
             $this->markTestSkipped('To run this test, add "phar" to the "suhosin.executor.include.whitelist" settings in your php.ini file.');
         }
 
@@ -609,7 +609,7 @@ class XmlFileLoaderTest extends TestCase
 
         $resources = $container->getResources();
 
-        $fixturesDir = dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures'.DIRECTORY_SEPARATOR;
+        $fixturesDir = \dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures'.DIRECTORY_SEPARATOR;
         $this->assertTrue(false !== array_search(new FileResource($fixturesDir.'xml'.DIRECTORY_SEPARATOR.'services_prototype.xml'), $resources));
         $this->assertTrue(false !== array_search(new GlobResource($fixturesDir.'Prototype', '/*', true), $resources));
         $resources = array_map('strval', $resources);
@@ -629,7 +629,7 @@ class XmlFileLoaderTest extends TestCase
 
         $resources = $container->getResources();
 
-        $fixturesDir = dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures'.DIRECTORY_SEPARATOR;
+        $fixturesDir = \dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures'.DIRECTORY_SEPARATOR;
         $this->assertTrue(false !== array_search(new FileResource($fixturesDir.'xml'.DIRECTORY_SEPARATOR.'services_prototype_array.xml'), $resources));
         $this->assertTrue(false !== array_search(new GlobResource($fixturesDir.'Prototype', '/*', true), $resources));
         $resources = array_map('strval', $resources);
diff --git a/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php b/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
index 4e9ca2a489..cd225b9505 100644
--- a/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
+++ b/src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php
@@ -363,7 +363,7 @@ class YamlFileLoaderTest extends TestCase
 
         $resources = $container->getResources();
 
-        $fixturesDir = dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures'.DIRECTORY_SEPARATOR;
+        $fixturesDir = \dirname(__DIR__).DIRECTORY_SEPARATOR.'Fixtures'.DIRECTORY_SEPARATOR;
         $this->assertTrue(false !== array_search(new FileResource($fixturesDir.'yaml'.DIRECTORY_SEPARATOR.'services_prototype.yml'), $resources));
         $this->assertTrue(false !== array_search(new GlobResource($fixturesDir.'Prototype', '', true), $resources));
         $resources = array_map('strval', $resources);
diff --git a/src/Symfony/Component/DomCrawler/AbstractUriElement.php b/src/Symfony/Component/DomCrawler/AbstractUriElement.php
index b477c71422..39ae522fd1 100644
--- a/src/Symfony/Component/DomCrawler/AbstractUriElement.php
+++ b/src/Symfony/Component/DomCrawler/AbstractUriElement.php
@@ -42,7 +42,7 @@ abstract class AbstractUriElement
      */
     public function __construct(\DOMElement $node, string $currentUri, ?string $method = 'GET')
     {
-        if (!in_array(strtolower(substr($currentUri, 0, 4)), array('http', 'file'))) {
+        if (!\in_array(strtolower(substr($currentUri, 0, 4)), array('http', 'file'))) {
             throw new \InvalidArgumentException(sprintf('Current URI must be an absolute URL ("%s").', $currentUri));
         }
 
@@ -114,7 +114,7 @@ abstract class AbstractUriElement
         }
 
         // relative path
-        $path = parse_url(substr($this->currentUri, strlen($baseUri)), PHP_URL_PATH);
+        $path = parse_url(substr($this->currentUri, \strlen($baseUri)), PHP_URL_PATH);
         $path = $this->canonicalizePath(substr($path, 0, strrpos($path, '/')).'/'.$uri);
 
         return $baseUri.('' === $path || '/' !== $path[0] ? '/' : '').$path;
diff --git a/src/Symfony/Component/DomCrawler/Crawler.php b/src/Symfony/Component/DomCrawler/Crawler.php
index 7b4d5170c1..489737909e 100644
--- a/src/Symfony/Component/DomCrawler/Crawler.php
+++ b/src/Symfony/Component/DomCrawler/Crawler.php
@@ -112,12 +112,12 @@ class Crawler implements \Countable, \IteratorAggregate
             $this->addNodeList($node);
         } elseif ($node instanceof \DOMNode) {
             $this->addNode($node);
-        } elseif (is_array($node)) {
+        } elseif (\is_array($node)) {
             $this->addNodes($node);
-        } elseif (is_string($node)) {
+        } elseif (\is_string($node)) {
             $this->addContent($node);
         } elseif (null !== $node) {
-            throw new \InvalidArgumentException(sprintf('Expecting a DOMNodeList or DOMNode instance, an array, a string, or null, but got "%s".', is_object($node) ? get_class($node) : gettype($node)));
+            throw new \InvalidArgumentException(sprintf('Expecting a DOMNodeList or DOMNode instance, an array, a string, or null, but got "%s".', \is_object($node) ? \get_class($node) : \gettype($node)));
         }
     }
 
@@ -211,7 +211,7 @@ class Crawler implements \Countable, \IteratorAggregate
         $base = $this->filterRelativeXPath('descendant-or-self::base')->extract(array('href'));
 
         $baseHref = current($base);
-        if (count($base) && !empty($baseHref)) {
+        if (\count($base) && !empty($baseHref)) {
             if ($this->baseHref) {
                 $linkNode = $dom->createElement('a');
                 $linkNode->setAttribute('href', $baseHref);
@@ -322,7 +322,7 @@ class Crawler implements \Countable, \IteratorAggregate
         }
 
         // Don't add duplicate nodes in the Crawler
-        if (in_array($node, $this->nodes, true)) {
+        if (\in_array($node, $this->nodes, true)) {
             return;
         }
 
@@ -381,7 +381,7 @@ class Crawler implements \Countable, \IteratorAggregate
      */
     public function slice($offset = 0, $length = null)
     {
-        return $this->createSubCrawler(array_slice($this->nodes, $offset, $length));
+        return $this->createSubCrawler(\array_slice($this->nodes, $offset, $length));
     }
 
     /**
@@ -422,7 +422,7 @@ class Crawler implements \Countable, \IteratorAggregate
      */
     public function last()
     {
-        return $this->eq(count($this->nodes) - 1);
+        return $this->eq(\count($this->nodes) - 1);
     }
 
     /**
@@ -635,7 +635,7 @@ class Crawler implements \Countable, \IteratorAggregate
     public function extract($attributes)
     {
         $attributes = (array) $attributes;
-        $count = count($attributes);
+        $count = \count($attributes);
 
         $data = array();
         foreach ($this->nodes as $node) {
@@ -761,7 +761,7 @@ class Crawler implements \Countable, \IteratorAggregate
         $node = $this->getNode(0);
 
         if (!$node instanceof \DOMElement) {
-            throw new \InvalidArgumentException(sprintf('The selected node should be instance of DOMElement, got "%s".', get_class($node)));
+            throw new \InvalidArgumentException(sprintf('The selected node should be instance of DOMElement, got "%s".', \get_class($node)));
         }
 
         return new Link($node, $this->baseHref, $method);
@@ -779,7 +779,7 @@ class Crawler implements \Countable, \IteratorAggregate
         $links = array();
         foreach ($this->nodes as $node) {
             if (!$node instanceof \DOMElement) {
-                throw new \InvalidArgumentException(sprintf('The current node list should contain only DOMElement instances, "%s" found.', get_class($node)));
+                throw new \InvalidArgumentException(sprintf('The current node list should contain only DOMElement instances, "%s" found.', \get_class($node)));
             }
 
             $links[] = new Link($node, $this->baseHref, 'get');
@@ -797,14 +797,14 @@ class Crawler implements \Countable, \IteratorAggregate
      */
     public function image()
     {
-        if (!count($this)) {
+        if (!\count($this)) {
             throw new \InvalidArgumentException('The current node list is empty.');
         }
 
         $node = $this->getNode(0);
 
         if (!$node instanceof \DOMElement) {
-            throw new \InvalidArgumentException(sprintf('The selected node should be instance of DOMElement, got "%s".', get_class($node)));
+            throw new \InvalidArgumentException(sprintf('The selected node should be instance of DOMElement, got "%s".', \get_class($node)));
         }
 
         return new Image($node, $this->baseHref);
@@ -820,7 +820,7 @@ class Crawler implements \Countable, \IteratorAggregate
         $images = array();
         foreach ($this as $node) {
             if (!$node instanceof \DOMElement) {
-                throw new \InvalidArgumentException(sprintf('The current node list should contain only DOMElement instances, "%s" found.', get_class($node)));
+                throw new \InvalidArgumentException(sprintf('The current node list should contain only DOMElement instances, "%s" found.', \get_class($node)));
             }
 
             $images[] = new Image($node, $this->baseHref);
@@ -848,7 +848,7 @@ class Crawler implements \Countable, \IteratorAggregate
         $node = $this->getNode(0);
 
         if (!$node instanceof \DOMElement) {
-            throw new \InvalidArgumentException(sprintf('The selected node should be instance of DOMElement, got "%s".', get_class($node)));
+            throw new \InvalidArgumentException(sprintf('The selected node should be instance of DOMElement, got "%s".', \get_class($node)));
         }
 
         $form = new Form($node, $this->uri, $method, $this->baseHref);
@@ -963,7 +963,7 @@ class Crawler implements \Countable, \IteratorAggregate
         // We cannot simply drop
         $nonMatchingExpression = 'a[name() = "b"]';
 
-        $xpathLen = strlen($xpath);
+        $xpathLen = \strlen($xpath);
         $openedBrackets = 0;
         $startPosition = strspn($xpath, " \t\n\r\0\x0B");
 
@@ -1056,7 +1056,7 @@ class Crawler implements \Countable, \IteratorAggregate
      */
     public function count()
     {
-        return count($this->nodes);
+        return \count($this->nodes);
     }
 
     /**
diff --git a/src/Symfony/Component/DomCrawler/Field/ChoiceFormField.php b/src/Symfony/Component/DomCrawler/Field/ChoiceFormField.php
index b24bbd879b..c5c5f05e4a 100644
--- a/src/Symfony/Component/DomCrawler/Field/ChoiceFormField.php
+++ b/src/Symfony/Component/DomCrawler/Field/ChoiceFormField.php
@@ -45,7 +45,7 @@ class ChoiceFormField extends FormField
     public function hasValue()
     {
         // don't send a value for unchecked checkboxes
-        if (in_array($this->type, array('checkbox', 'radio')) && null === $this->value) {
+        if (\in_array($this->type, array('checkbox', 'radio')) && null === $this->value) {
             return false;
         }
 
@@ -126,7 +126,7 @@ class ChoiceFormField extends FormField
             // check
             $this->value = $this->options[0]['value'];
         } else {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 if (!$this->multiple) {
                     throw new \InvalidArgumentException(sprintf('The value for "%s" cannot be an array.', $this->name));
                 }
@@ -144,7 +144,7 @@ class ChoiceFormField extends FormField
                 $value = (array) $value;
             }
 
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $this->value = $value;
             } else {
                 parent::setValue($value);
diff --git a/src/Symfony/Component/DomCrawler/Field/FileFormField.php b/src/Symfony/Component/DomCrawler/Field/FileFormField.php
index fc21239f01..3288fc135a 100644
--- a/src/Symfony/Component/DomCrawler/Field/FileFormField.php
+++ b/src/Symfony/Component/DomCrawler/Field/FileFormField.php
@@ -28,7 +28,7 @@ class FileFormField extends FormField
     public function setErrorCode($error)
     {
         $codes = array(UPLOAD_ERR_INI_SIZE, UPLOAD_ERR_FORM_SIZE, UPLOAD_ERR_PARTIAL, UPLOAD_ERR_NO_FILE, UPLOAD_ERR_NO_TMP_DIR, UPLOAD_ERR_CANT_WRITE, UPLOAD_ERR_EXTENSION);
-        if (!in_array($error, $codes)) {
+        if (!\in_array($error, $codes)) {
             throw new \InvalidArgumentException(sprintf('The error code %s is not valid.', $error));
         }
 
diff --git a/src/Symfony/Component/DomCrawler/Form.php b/src/Symfony/Component/DomCrawler/Form.php
index 6988d50967..08d2295c8f 100644
--- a/src/Symfony/Component/DomCrawler/Form.php
+++ b/src/Symfony/Component/DomCrawler/Form.php
@@ -108,7 +108,7 @@ class Form extends Link implements \ArrayAccess
      */
     public function getFiles()
     {
-        if (!in_array($this->getMethod(), array('POST', 'PUT', 'DELETE', 'PATCH'))) {
+        if (!\in_array($this->getMethod(), array('POST', 'PUT', 'DELETE', 'PATCH'))) {
             return array();
         }
 
@@ -142,7 +142,7 @@ class Form extends Link implements \ArrayAccess
             $qs = http_build_query(array($name => $value), '', '&');
             if (!empty($qs)) {
                 parse_str($qs, $expandedValue);
-                $varName = substr($name, 0, strlen(key($expandedValue)));
+                $varName = substr($name, 0, \strlen(key($expandedValue)));
                 $values = array_replace_recursive($values, array($varName => current($expandedValue)));
             }
         }
@@ -169,7 +169,7 @@ class Form extends Link implements \ArrayAccess
             $qs = http_build_query(array($name => $value), '', '&');
             if (!empty($qs)) {
                 parse_str($qs, $expandedValue);
-                $varName = substr($name, 0, strlen(key($expandedValue)));
+                $varName = substr($name, 0, \strlen(key($expandedValue)));
 
                 array_walk_recursive(
                     $expandedValue,
@@ -202,7 +202,7 @@ class Form extends Link implements \ArrayAccess
     {
         $uri = parent::getUri();
 
-        if (!in_array($this->getMethod(), array('POST', 'PUT', 'DELETE', 'PATCH'))) {
+        if (!\in_array($this->getMethod(), array('POST', 'PUT', 'DELETE', 'PATCH'))) {
             $query = parse_url($uri, PHP_URL_QUERY);
             $currentParameters = array();
             if ($query) {
@@ -379,7 +379,7 @@ class Form extends Link implements \ArrayAccess
     protected function setNode(\DOMElement $node)
     {
         $this->button = $node;
-        if ('button' === $node->nodeName || ('input' === $node->nodeName && in_array(strtolower($node->getAttribute('type')), array('submit', 'button', 'image')))) {
+        if ('button' === $node->nodeName || ('input' === $node->nodeName && \in_array(strtolower($node->getAttribute('type')), array('submit', 'button', 'image')))) {
             if ($node->hasAttribute('form')) {
                 // if the node has the HTML5-compliant 'form' attribute, use it
                 $formId = $node->getAttribute('form');
@@ -480,7 +480,7 @@ class Form extends Link implements \ArrayAccess
             }
         } elseif ('input' == $nodeName && 'file' == strtolower($node->getAttribute('type'))) {
             $this->set(new Field\FileFormField($node));
-        } elseif ('input' == $nodeName && !in_array(strtolower($node->getAttribute('type')), array('submit', 'button', 'image'))) {
+        } elseif ('input' == $nodeName && !\in_array(strtolower($node->getAttribute('type')), array('submit', 'button', 'image'))) {
             $this->set(new Field\InputFormField($node));
         } elseif ('textarea' == $nodeName) {
             $this->set(new Field\TextareaFormField($node));
diff --git a/src/Symfony/Component/DomCrawler/FormFieldRegistry.php b/src/Symfony/Component/DomCrawler/FormFieldRegistry.php
index 6ad6d933e4..d2acb15ada 100644
--- a/src/Symfony/Component/DomCrawler/FormFieldRegistry.php
+++ b/src/Symfony/Component/DomCrawler/FormFieldRegistry.php
@@ -33,7 +33,7 @@ class FormFieldRegistry
 
         $target = &$this->fields;
         while ($segments) {
-            if (!is_array($target)) {
+            if (!\is_array($target)) {
                 $target = array();
             }
             $path = array_shift($segments);
@@ -55,7 +55,7 @@ class FormFieldRegistry
     {
         $segments = $this->getSegments($name);
         $target = &$this->fields;
-        while (count($segments) > 1) {
+        while (\count($segments) > 1) {
             $path = array_shift($segments);
             if (!array_key_exists($path, $target)) {
                 return;
@@ -118,9 +118,9 @@ class FormFieldRegistry
     public function set($name, $value)
     {
         $target = &$this->get($name);
-        if ((!is_array($value) && $target instanceof Field\FormField) || $target instanceof Field\ChoiceFormField) {
+        if ((!\is_array($value) && $target instanceof Field\FormField) || $target instanceof Field\ChoiceFormField) {
             $target->setValue($value);
-        } elseif (is_array($value)) {
+        } elseif (\is_array($value)) {
             $fields = self::create($name, $value);
             foreach ($fields->all() as $k => $v) {
                 $this->set($k, $v);
@@ -173,7 +173,7 @@ class FormFieldRegistry
     {
         foreach ($array as $k => $v) {
             $path = empty($base) ? $k : sprintf('%s[%s]', $base, $k);
-            if (is_array($v)) {
+            if (\is_array($v)) {
                 $this->walk($v, $path, $output);
             } else {
                 $output[$path] = $v;
diff --git a/src/Symfony/Component/DomCrawler/Tests/FormTest.php b/src/Symfony/Component/DomCrawler/Tests/FormTest.php
index 90e87d4c00..2f653d6c58 100644
--- a/src/Symfony/Component/DomCrawler/Tests/FormTest.php
+++ b/src/Symfony/Component/DomCrawler/Tests/FormTest.php
@@ -191,7 +191,7 @@ class FormTest extends TestCase
             $values,
             array_map(
                 function ($field) {
-                    $class = get_class($field);
+                    $class = \get_class($field);
 
                     return array(substr($class, strrpos($class, '\\') + 1), $field->getValue());
                 },
diff --git a/src/Symfony/Component/Dotenv/Dotenv.php b/src/Symfony/Component/Dotenv/Dotenv.php
index c97f166bef..9756cdb16c 100644
--- a/src/Symfony/Component/Dotenv/Dotenv.php
+++ b/src/Symfony/Component/Dotenv/Dotenv.php
@@ -110,7 +110,7 @@ final class Dotenv
         $this->data = str_replace(array("\r\n", "\r"), "\n", $data);
         $this->lineno = 1;
         $this->cursor = 0;
-        $this->end = strlen($this->data);
+        $this->end = \strlen($this->data);
         $this->state = self::STATE_VARNAME;
         $this->values = array();
         $name = '';
@@ -232,7 +232,7 @@ final class Dotenv
             } else {
                 $value = '';
                 $prevChr = $this->data[$this->cursor - 1];
-                while ($this->cursor < $this->end && !in_array($this->data[$this->cursor], array("\n", '"', "'"), true) && !((' ' === $prevChr || "\t" === $prevChr) && '#' === $this->data[$this->cursor])) {
+                while ($this->cursor < $this->end && !\in_array($this->data[$this->cursor], array("\n", '"', "'"), true) && !((' ' === $prevChr || "\t" === $prevChr) && '#' === $this->data[$this->cursor])) {
                     if ('\\' === $this->data[$this->cursor] && isset($this->data[$this->cursor + 1]) && ('"' === $this->data[$this->cursor + 1] || "'" === $this->data[$this->cursor + 1])) {
                         ++$this->cursor;
                     }
@@ -391,7 +391,7 @@ final class Dotenv
 
     private function moveCursor($text)
     {
-        $this->cursor += strlen($text);
+        $this->cursor += \strlen($text);
         $this->lineno += substr_count($text, "\n");
     }
 
diff --git a/src/Symfony/Component/Dotenv/Exception/FormatExceptionContext.php b/src/Symfony/Component/Dotenv/Exception/FormatExceptionContext.php
index 995477cf89..c1d32d4a7e 100644
--- a/src/Symfony/Component/Dotenv/Exception/FormatExceptionContext.php
+++ b/src/Symfony/Component/Dotenv/Exception/FormatExceptionContext.php
@@ -44,6 +44,6 @@ final class FormatExceptionContext
         $before = str_replace("\n", '\n', substr($this->data, max(0, $this->cursor - 20), min(20, $this->cursor)));
         $after = str_replace("\n", '\n', substr($this->data, $this->cursor, 20));
 
-        return '...'.$before.$after."...\n".str_repeat(' ', strlen($before) + 2).'^ line '.$this->lineno.' offset '.$this->cursor;
+        return '...'.$before.$after."...\n".str_repeat(' ', \strlen($before) + 2).'^ line '.$this->lineno.' offset '.$this->cursor;
     }
 }
diff --git a/src/Symfony/Component/EventDispatcher/Debug/TraceableEventDispatcher.php b/src/Symfony/Component/EventDispatcher/Debug/TraceableEventDispatcher.php
index 8d851623fb..0e658378ce 100644
--- a/src/Symfony/Component/EventDispatcher/Debug/TraceableEventDispatcher.php
+++ b/src/Symfony/Component/EventDispatcher/Debug/TraceableEventDispatcher.php
@@ -230,7 +230,7 @@ class TraceableEventDispatcher implements TraceableEventDispatcherInterface
      */
     public function __call($method, $arguments)
     {
-        return call_user_func_array(array($this->dispatcher, $method), $arguments);
+        return \call_user_func_array(array($this->dispatcher, $method), $arguments);
     }
 
     /**
@@ -315,11 +315,11 @@ class TraceableEventDispatcher implements TraceableEventDispatcherInterface
 
     private function sortListenersByPriority($a, $b)
     {
-        if (is_int($a['priority']) && !is_int($b['priority'])) {
+        if (\is_int($a['priority']) && !\is_int($b['priority'])) {
             return 1;
         }
 
-        if (!is_int($a['priority']) && is_int($b['priority'])) {
+        if (!\is_int($a['priority']) && \is_int($b['priority'])) {
             return -1;
         }
 
diff --git a/src/Symfony/Component/EventDispatcher/Debug/WrappedListener.php b/src/Symfony/Component/EventDispatcher/Debug/WrappedListener.php
index f7b0273e15..12632b78c6 100644
--- a/src/Symfony/Component/EventDispatcher/Debug/WrappedListener.php
+++ b/src/Symfony/Component/EventDispatcher/Debug/WrappedListener.php
@@ -40,15 +40,15 @@ class WrappedListener
         $this->called = false;
         $this->stoppedPropagation = false;
 
-        if (is_array($listener)) {
-            $this->name = is_object($listener[0]) ? get_class($listener[0]) : $listener[0];
+        if (\is_array($listener)) {
+            $this->name = \is_object($listener[0]) ? \get_class($listener[0]) : $listener[0];
             $this->pretty = $this->name.'::'.$listener[1];
         } elseif ($listener instanceof \Closure) {
             $this->pretty = $this->name = 'closure';
-        } elseif (is_string($listener)) {
+        } elseif (\is_string($listener)) {
             $this->pretty = $this->name = $listener;
         } else {
-            $this->name = get_class($listener);
+            $this->name = \get_class($listener);
             $this->pretty = $this->name.'::__invoke';
         }
 
@@ -101,7 +101,7 @@ class WrappedListener
 
         $e = $this->stopwatch->start($this->name, 'event_listener');
 
-        call_user_func($this->listener, $event, $eventName, $this->dispatcher ?: $dispatcher);
+        \call_user_func($this->listener, $event, $eventName, $this->dispatcher ?: $dispatcher);
 
         if ($e->isStarted()) {
             $e->stop();
diff --git a/src/Symfony/Component/EventDispatcher/EventDispatcher.php b/src/Symfony/Component/EventDispatcher/EventDispatcher.php
index bc79a958da..4e75c63e4f 100644
--- a/src/Symfony/Component/EventDispatcher/EventDispatcher.php
+++ b/src/Symfony/Component/EventDispatcher/EventDispatcher.php
@@ -82,13 +82,13 @@ class EventDispatcher implements EventDispatcherInterface
             return;
         }
 
-        if (is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
+        if (\is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
             $listener[0] = $listener[0]();
         }
 
         foreach ($this->listeners[$eventName] as $priority => $listeners) {
             foreach ($listeners as $k => $v) {
-                if ($v !== $listener && is_array($v) && isset($v[0]) && $v[0] instanceof \Closure) {
+                if ($v !== $listener && \is_array($v) && isset($v[0]) && $v[0] instanceof \Closure) {
                     $v[0] = $v[0]();
                     $this->listeners[$eventName][$priority][$k] = $v;
                 }
@@ -135,13 +135,13 @@ class EventDispatcher implements EventDispatcherInterface
             return;
         }
 
-        if (is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
+        if (\is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
             $listener[0] = $listener[0]();
         }
 
         foreach ($this->listeners[$eventName] as $priority => $listeners) {
             foreach ($listeners as $k => $v) {
-                if ($v !== $listener && is_array($v) && isset($v[0]) && $v[0] instanceof \Closure) {
+                if ($v !== $listener && \is_array($v) && isset($v[0]) && $v[0] instanceof \Closure) {
                     $v[0] = $v[0]();
                 }
                 if ($v === $listener) {
@@ -165,9 +165,9 @@ class EventDispatcher implements EventDispatcherInterface
     public function addSubscriber(EventSubscriberInterface $subscriber)
     {
         foreach ($subscriber->getSubscribedEvents() as $eventName => $params) {
-            if (is_string($params)) {
+            if (\is_string($params)) {
                 $this->addListener($eventName, array($subscriber, $params));
-            } elseif (is_string($params[0])) {
+            } elseif (\is_string($params[0])) {
                 $this->addListener($eventName, array($subscriber, $params[0]), isset($params[1]) ? $params[1] : 0);
             } else {
                 foreach ($params as $listener) {
@@ -183,12 +183,12 @@ class EventDispatcher implements EventDispatcherInterface
     public function removeSubscriber(EventSubscriberInterface $subscriber)
     {
         foreach ($subscriber->getSubscribedEvents() as $eventName => $params) {
-            if (is_array($params) && is_array($params[0])) {
+            if (\is_array($params) && \is_array($params[0])) {
                 foreach ($params as $listener) {
                     $this->removeListener($eventName, array($subscriber, $listener[0]));
                 }
             } else {
-                $this->removeListener($eventName, array($subscriber, is_string($params) ? $params : $params[0]));
+                $this->removeListener($eventName, array($subscriber, \is_string($params) ? $params : $params[0]));
             }
         }
     }
diff --git a/src/Symfony/Component/ExpressionLanguage/Compiler.php b/src/Symfony/Component/ExpressionLanguage/Compiler.php
index c048958518..23222d40e9 100644
--- a/src/Symfony/Component/ExpressionLanguage/Compiler.php
+++ b/src/Symfony/Component/ExpressionLanguage/Compiler.php
@@ -112,7 +112,7 @@ class Compiler implements ResetInterface
      */
     public function repr($value)
     {
-        if (is_int($value) || is_float($value)) {
+        if (\is_int($value) || \is_float($value)) {
             if (false !== $locale = setlocale(LC_NUMERIC, 0)) {
                 setlocale(LC_NUMERIC, 'C');
             }
@@ -124,9 +124,9 @@ class Compiler implements ResetInterface
             }
         } elseif (null === $value) {
             $this->raw('null');
-        } elseif (is_bool($value)) {
+        } elseif (\is_bool($value)) {
             $this->raw($value ? 'true' : 'false');
-        } elseif (is_array($value)) {
+        } elseif (\is_array($value)) {
             $this->raw('array(');
             $first = true;
             foreach ($value as $key => $value) {
diff --git a/src/Symfony/Component/ExpressionLanguage/ExpressionFunction.php b/src/Symfony/Component/ExpressionLanguage/ExpressionFunction.php
index 448cd466f0..968d80fa9c 100644
--- a/src/Symfony/Component/ExpressionLanguage/ExpressionFunction.php
+++ b/src/Symfony/Component/ExpressionLanguage/ExpressionFunction.php
@@ -76,23 +76,23 @@ class ExpressionFunction
     public static function fromPhp($phpFunctionName, $expressionFunctionName = null)
     {
         $phpFunctionName = ltrim($phpFunctionName, '\\');
-        if (!function_exists($phpFunctionName)) {
+        if (!\function_exists($phpFunctionName)) {
             throw new \InvalidArgumentException(sprintf('PHP function "%s" does not exist.', $phpFunctionName));
         }
 
         $parts = explode('\\', $phpFunctionName);
-        if (!$expressionFunctionName && count($parts) > 1) {
+        if (!$expressionFunctionName && \count($parts) > 1) {
             throw new \InvalidArgumentException(sprintf('An expression function name must be defined when PHP function "%s" is namespaced.', $phpFunctionName));
         }
 
         $compiler = function () use ($phpFunctionName) {
-            return sprintf('\%s(%s)', $phpFunctionName, implode(', ', func_get_args()));
+            return sprintf('\%s(%s)', $phpFunctionName, implode(', ', \func_get_args()));
         };
 
         $evaluator = function () use ($phpFunctionName) {
-            $args = func_get_args();
+            $args = \func_get_args();
 
-            return call_user_func_array($phpFunctionName, array_splice($args, 1));
+            return \call_user_func_array($phpFunctionName, array_splice($args, 1));
         };
 
         return new self($expressionFunctionName ?: end($parts), $compiler, $evaluator);
diff --git a/src/Symfony/Component/ExpressionLanguage/ExpressionLanguage.php b/src/Symfony/Component/ExpressionLanguage/ExpressionLanguage.php
index 342600c20f..851fe00157 100644
--- a/src/Symfony/Component/ExpressionLanguage/ExpressionLanguage.php
+++ b/src/Symfony/Component/ExpressionLanguage/ExpressionLanguage.php
@@ -85,7 +85,7 @@ class ExpressionLanguage
         $cacheKeyItems = array();
 
         foreach ($names as $nameKey => $name) {
-            $cacheKeyItems[] = is_int($nameKey) ? $name : $nameKey.':'.$name;
+            $cacheKeyItems[] = \is_int($nameKey) ? $name : $nameKey.':'.$name;
         }
 
         $cacheItem = $this->cache->getItem(rawurlencode($expression.'//'.implode('|', $cacheKeyItems)));
diff --git a/src/Symfony/Component/ExpressionLanguage/Lexer.php b/src/Symfony/Component/ExpressionLanguage/Lexer.php
index aeeda8a856..bd54e8913a 100644
--- a/src/Symfony/Component/ExpressionLanguage/Lexer.php
+++ b/src/Symfony/Component/ExpressionLanguage/Lexer.php
@@ -33,7 +33,7 @@ class Lexer
         $cursor = 0;
         $tokens = array();
         $brackets = array();
-        $end = strlen($expression);
+        $end = \strlen($expression);
 
         while ($cursor < $end) {
             if (' ' == $expression[$cursor]) {
@@ -49,7 +49,7 @@ class Lexer
                     $number = (int) $match[0]; // integers lower than the maximum
                 }
                 $tokens[] = new Token(Token::NUMBER_TYPE, $number, $cursor + 1);
-                $cursor += strlen($match[0]);
+                $cursor += \strlen($match[0]);
             } elseif (false !== strpos('([{', $expression[$cursor])) {
                 // opening bracket
                 $brackets[] = array($expression[$cursor], $cursor);
@@ -72,11 +72,11 @@ class Lexer
             } elseif (preg_match('/"([^"\\\\]*(?:\\\\.[^"\\\\]*)*)"|\'([^\'\\\\]*(?:\\\\.[^\'\\\\]*)*)\'/As', $expression, $match, 0, $cursor)) {
                 // strings
                 $tokens[] = new Token(Token::STRING_TYPE, stripcslashes(substr($match[0], 1, -1)), $cursor + 1);
-                $cursor += strlen($match[0]);
+                $cursor += \strlen($match[0]);
             } elseif (preg_match('/not in(?=[\s(])|\!\=\=|not(?=[\s(])|and(?=[\s(])|\=\=\=|\>\=|or(?=[\s(])|\<\=|\*\*|\.\.|in(?=[\s(])|&&|\|\||matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) {
                 // operators
                 $tokens[] = new Token(Token::OPERATOR_TYPE, $match[0], $cursor + 1);
-                $cursor += strlen($match[0]);
+                $cursor += \strlen($match[0]);
             } elseif (false !== strpos('.,?:', $expression[$cursor])) {
                 // punctuation
                 $tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1);
@@ -84,7 +84,7 @@ class Lexer
             } elseif (preg_match('/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/A', $expression, $match, 0, $cursor)) {
                 // names
                 $tokens[] = new Token(Token::NAME_TYPE, $match[0], $cursor + 1);
-                $cursor += strlen($match[0]);
+                $cursor += \strlen($match[0]);
             } else {
                 // unlexable
                 throw new SyntaxError(sprintf('Unexpected character "%s"', $expression[$cursor]), $cursor, $expression);
diff --git a/src/Symfony/Component/ExpressionLanguage/Node/BinaryNode.php b/src/Symfony/Component/ExpressionLanguage/Node/BinaryNode.php
index 26b456145c..48c6548fa8 100644
--- a/src/Symfony/Component/ExpressionLanguage/Node/BinaryNode.php
+++ b/src/Symfony/Component/ExpressionLanguage/Node/BinaryNode.php
@@ -93,7 +93,7 @@ class BinaryNode extends Node
             $right = $this->nodes['right']->evaluate($functions, $values);
 
             if ('not in' === $operator) {
-                return !in_array($left, $right);
+                return !\in_array($left, $right);
             }
             $f = self::$functions[$operator];
 
@@ -135,9 +135,9 @@ class BinaryNode extends Node
             case '<=':
                 return $left <= $right;
             case 'not in':
-                return !in_array($left, $right);
+                return !\in_array($left, $right);
             case 'in':
-                return in_array($left, $right);
+                return \in_array($left, $right);
             case '+':
                 return $left + $right;
             case '-':
diff --git a/src/Symfony/Component/ExpressionLanguage/Node/ConstantNode.php b/src/Symfony/Component/ExpressionLanguage/Node/ConstantNode.php
index d1bd7c69e8..de2c48f10d 100644
--- a/src/Symfony/Component/ExpressionLanguage/Node/ConstantNode.php
+++ b/src/Symfony/Component/ExpressionLanguage/Node/ConstantNode.php
@@ -56,7 +56,7 @@ class ConstantNode extends Node
             $array[] = 'null';
         } elseif (is_numeric($value)) {
             $array[] = $value;
-        } elseif (!is_array($value)) {
+        } elseif (!\is_array($value)) {
             $array[] = $this->dumpString($value);
         } elseif ($this->isHash($value)) {
             foreach ($value as $k => $v) {
diff --git a/src/Symfony/Component/ExpressionLanguage/Node/FunctionNode.php b/src/Symfony/Component/ExpressionLanguage/Node/FunctionNode.php
index e3424b50d4..1a1ad4336b 100644
--- a/src/Symfony/Component/ExpressionLanguage/Node/FunctionNode.php
+++ b/src/Symfony/Component/ExpressionLanguage/Node/FunctionNode.php
@@ -37,7 +37,7 @@ class FunctionNode extends Node
 
         $function = $compiler->getFunction($this->attributes['name']);
 
-        $compiler->raw(call_user_func_array($function['compiler'], $arguments));
+        $compiler->raw(\call_user_func_array($function['compiler'], $arguments));
     }
 
     public function evaluate($functions, $values)
@@ -47,7 +47,7 @@ class FunctionNode extends Node
             $arguments[] = $node->evaluate($functions, $values);
         }
 
-        return call_user_func_array($functions[$this->attributes['name']]['evaluator'], $arguments);
+        return \call_user_func_array($functions[$this->attributes['name']]['evaluator'], $arguments);
     }
 
     public function toArray()
diff --git a/src/Symfony/Component/ExpressionLanguage/Node/GetAttrNode.php b/src/Symfony/Component/ExpressionLanguage/Node/GetAttrNode.php
index bafd227b48..6a8b47ce1a 100644
--- a/src/Symfony/Component/ExpressionLanguage/Node/GetAttrNode.php
+++ b/src/Symfony/Component/ExpressionLanguage/Node/GetAttrNode.php
@@ -69,7 +69,7 @@ class GetAttrNode extends Node
         switch ($this->attributes['type']) {
             case self::PROPERTY_CALL:
                 $obj = $this->nodes['node']->evaluate($functions, $values);
-                if (!is_object($obj)) {
+                if (!\is_object($obj)) {
                     throw new \RuntimeException('Unable to get a property on a non-object.');
                 }
 
@@ -79,18 +79,18 @@ class GetAttrNode extends Node
 
             case self::METHOD_CALL:
                 $obj = $this->nodes['node']->evaluate($functions, $values);
-                if (!is_object($obj)) {
+                if (!\is_object($obj)) {
                     throw new \RuntimeException('Unable to get a property on a non-object.');
                 }
-                if (!is_callable($toCall = array($obj, $this->nodes['attribute']->attributes['value']))) {
-                    throw new \RuntimeException(sprintf('Unable to call method "%s" of object "%s".', $this->nodes['attribute']->attributes['value'], get_class($obj)));
+                if (!\is_callable($toCall = array($obj, $this->nodes['attribute']->attributes['value']))) {
+                    throw new \RuntimeException(sprintf('Unable to call method "%s" of object "%s".', $this->nodes['attribute']->attributes['value'], \get_class($obj)));
                 }
 
-                return call_user_func_array($toCall, $this->nodes['arguments']->evaluate($functions, $values));
+                return \call_user_func_array($toCall, $this->nodes['arguments']->evaluate($functions, $values));
 
             case self::ARRAY_CALL:
                 $array = $this->nodes['node']->evaluate($functions, $values);
-                if (!is_array($array) && !$array instanceof \ArrayAccess) {
+                if (!\is_array($array) && !$array instanceof \ArrayAccess) {
                     throw new \RuntimeException('Unable to get an item on a non-array.');
                 }
 
diff --git a/src/Symfony/Component/ExpressionLanguage/Node/Node.php b/src/Symfony/Component/ExpressionLanguage/Node/Node.php
index 1db4e85280..c6eb9f0351 100644
--- a/src/Symfony/Component/ExpressionLanguage/Node/Node.php
+++ b/src/Symfony/Component/ExpressionLanguage/Node/Node.php
@@ -40,9 +40,9 @@ class Node
             $attributes[] = sprintf('%s: %s', $name, str_replace("\n", '', var_export($value, true)));
         }
 
-        $repr = array(str_replace('Symfony\Component\ExpressionLanguage\Node\\', '', get_class($this)).'('.implode(', ', $attributes));
+        $repr = array(str_replace('Symfony\Component\ExpressionLanguage\Node\\', '', \get_class($this)).'('.implode(', ', $attributes));
 
-        if (count($this->nodes)) {
+        if (\count($this->nodes)) {
             foreach ($this->nodes as $node) {
                 foreach (explode("\n", (string) $node) as $line) {
                     $repr[] = '    '.$line;
@@ -76,7 +76,7 @@ class Node
 
     public function toArray()
     {
-        throw new \BadMethodCallException(sprintf('Dumping a "%s" instance is not supported yet.', get_class($this)));
+        throw new \BadMethodCallException(sprintf('Dumping a "%s" instance is not supported yet.', \get_class($this)));
     }
 
     public function dump()
diff --git a/src/Symfony/Component/ExpressionLanguage/Parser.php b/src/Symfony/Component/ExpressionLanguage/Parser.php
index 4b1ce8e3a1..a3b31ce976 100644
--- a/src/Symfony/Component/ExpressionLanguage/Parser.php
+++ b/src/Symfony/Component/ExpressionLanguage/Parser.php
@@ -200,13 +200,13 @@ class Parser
 
                             $node = new Node\FunctionNode($token->value, $this->parseArguments());
                         } else {
-                            if (!in_array($token->value, $this->names, true)) {
+                            if (!\in_array($token->value, $this->names, true)) {
                                 throw new SyntaxError(sprintf('Variable "%s" is not valid', $token->value), $token->cursor, $this->stream->getExpression(), $token->value, $this->names);
                             }
 
                             // is the name used in the compiled code different
                             // from the name used in the expression?
-                            if (is_int($name = array_search($token->value, $this->names))) {
+                            if (\is_int($name = array_search($token->value, $this->names))) {
                                 $name = $token->value;
                             }
 
diff --git a/src/Symfony/Component/ExpressionLanguage/Tests/LexerTest.php b/src/Symfony/Component/ExpressionLanguage/Tests/LexerTest.php
index 87c16f707b..16bf450862 100644
--- a/src/Symfony/Component/ExpressionLanguage/Tests/LexerTest.php
+++ b/src/Symfony/Component/ExpressionLanguage/Tests/LexerTest.php
@@ -33,7 +33,7 @@ class LexerTest extends TestCase
      */
     public function testTokenize($tokens, $expression)
     {
-        $tokens[] = new Token('end of expression', null, strlen($expression) + 1);
+        $tokens[] = new Token('end of expression', null, \strlen($expression) + 1);
         $this->assertEquals(new TokenStream($tokens, $expression), $this->lexer->tokenize($expression));
     }
 
diff --git a/src/Symfony/Component/Filesystem/Filesystem.php b/src/Symfony/Component/Filesystem/Filesystem.php
index 046dbb940e..b4a9c9816f 100644
--- a/src/Symfony/Component/Filesystem/Filesystem.php
+++ b/src/Symfony/Component/Filesystem/Filesystem.php
@@ -45,7 +45,7 @@ class Filesystem
             throw new FileNotFoundException(sprintf('Failed to copy "%s" because file does not exist.', $originFile), 0, null, $originFile);
         }
 
-        $this->mkdir(dirname($targetFile));
+        $this->mkdir(\dirname($targetFile));
 
         $doCopy = true;
         if (!$overwriteNewerFiles && null === parse_url($originFile, PHP_URL_HOST) && is_file($targetFile)) {
@@ -122,7 +122,7 @@ class Filesystem
         $maxPathLength = PHP_MAXPATHLEN - 2;
 
         foreach ($this->toIterable($files) as $file) {
-            if (strlen($file) > $maxPathLength) {
+            if (\strlen($file) > $maxPathLength) {
                 throw new IOException(sprintf('Could not check if file exist because path length exceeds %d characters.', $maxPathLength), 0, null, $file);
             }
 
@@ -164,7 +164,7 @@ class Filesystem
     {
         if ($files instanceof \Traversable) {
             $files = iterator_to_array($files, false);
-        } elseif (!is_array($files)) {
+        } elseif (!\is_array($files)) {
             $files = array($files);
         }
         $files = array_reverse($files);
@@ -223,7 +223,7 @@ class Filesystem
             if ($recursive && is_dir($file) && !is_link($file)) {
                 $this->chown(new \FilesystemIterator($file), $user, true);
             }
-            if (is_link($file) && function_exists('lchown')) {
+            if (is_link($file) && \function_exists('lchown')) {
                 if (true !== @lchown($file, $user)) {
                     throw new IOException(sprintf('Failed to chown file "%s".', $file), 0, null, $file);
                 }
@@ -250,7 +250,7 @@ class Filesystem
             if ($recursive && is_dir($file) && !is_link($file)) {
                 $this->chgrp(new \FilesystemIterator($file), $group, true);
             }
-            if (is_link($file) && function_exists('lchgrp')) {
+            if (is_link($file) && \function_exists('lchgrp')) {
                 if (true !== @lchgrp($file, $group)) {
                     throw new IOException(sprintf('Failed to chgrp file "%s".', $file), 0, null, $file);
                 }
@@ -304,7 +304,7 @@ class Filesystem
     {
         $maxPathLength = PHP_MAXPATHLEN - 2;
 
-        if (strlen($filename) > $maxPathLength) {
+        if (\strlen($filename) > $maxPathLength) {
             throw new IOException(sprintf('Could not check if file is readable because path length exceeds %d characters.', $maxPathLength), 0, null, $filename);
         }
 
@@ -333,7 +333,7 @@ class Filesystem
             }
         }
 
-        $this->mkdir(dirname($targetDir));
+        $this->mkdir(\dirname($targetDir));
 
         if (is_link($targetDir)) {
             if (readlink($targetDir) === $originDir) {
@@ -461,7 +461,7 @@ class Filesystem
         }
 
         $stripDriveLetter = function ($path) {
-            if (strlen($path) > 2 && ':' === $path[1] && '/' === $path[2] && ctype_alpha($path[0])) {
+            if (\strlen($path) > 2 && ':' === $path[1] && '/' === $path[2] && ctype_alpha($path[0])) {
                 return substr($path, 2);
             }
 
@@ -499,16 +499,16 @@ class Filesystem
         }
 
         // Determine how deep the start path is relative to the common path (ie, "web/bundles" = 2 levels)
-        if (1 === count($startPathArr) && '' === $startPathArr[0]) {
+        if (1 === \count($startPathArr) && '' === $startPathArr[0]) {
             $depth = 0;
         } else {
-            $depth = count($startPathArr) - $index;
+            $depth = \count($startPathArr) - $index;
         }
 
         // Repeated "../" for each level need to reach the common path
         $traverser = str_repeat('../', $depth);
 
-        $endPathRemainder = implode('/', array_slice($endPathArr, $index));
+        $endPathRemainder = implode('/', \array_slice($endPathArr, $index));
 
         // Construct $endPath from traversing to the common path, then to the remaining $endPath
         $relativePath = $traverser.('' !== $endPathRemainder ? $endPathRemainder.'/' : '');
@@ -539,7 +539,7 @@ class Filesystem
     {
         $targetDir = rtrim($targetDir, '/\\');
         $originDir = rtrim($originDir, '/\\');
-        $originDirLen = strlen($originDir);
+        $originDirLen = \strlen($originDir);
 
         // Iterate in destination folder to remove obsolete entries
         if ($this->exists($targetDir) && isset($options['delete']) && $options['delete']) {
@@ -548,7 +548,7 @@ class Filesystem
                 $flags = \FilesystemIterator::SKIP_DOTS;
                 $deleteIterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($targetDir, $flags), \RecursiveIteratorIterator::CHILD_FIRST);
             }
-            $targetDirLen = strlen($targetDir);
+            $targetDirLen = \strlen($targetDir);
             foreach ($deleteIterator as $file) {
                 $origin = $originDir.substr($file->getPathname(), $targetDirLen);
                 if (!$this->exists($origin)) {
@@ -606,7 +606,7 @@ class Filesystem
     public function isAbsolutePath($file)
     {
         return strspn($file, '/\\', 0, 1)
-            || (strlen($file) > 3 && ctype_alpha($file[0])
+            || (\strlen($file) > 3 && ctype_alpha($file[0])
                 && ':' === $file[1]
                 && strspn($file, '/\\', 2, 1)
             )
@@ -676,7 +676,7 @@ class Filesystem
      */
     public function dumpFile($filename, $content)
     {
-        $dir = dirname($filename);
+        $dir = \dirname($filename);
 
         if (!is_dir($dir)) {
             $this->mkdir($dir);
@@ -709,7 +709,7 @@ class Filesystem
      */
     public function appendToFile($filename, $content)
     {
-        $dir = dirname($filename);
+        $dir = \dirname($filename);
 
         if (!is_dir($dir)) {
             $this->mkdir($dir);
@@ -726,7 +726,7 @@ class Filesystem
 
     private function toIterable($files): iterable
     {
-        return is_array($files) || $files instanceof \Traversable ? $files : array($files);
+        return \is_array($files) || $files instanceof \Traversable ? $files : array($files);
     }
 
     /**
@@ -736,7 +736,7 @@ class Filesystem
     {
         $components = explode('://', $filename, 2);
 
-        return 2 === count($components) ? array($components[0], $components[1]) : array(null, $components[0]);
+        return 2 === \count($components) ? array($components[0], $components[1]) : array(null, $components[0]);
     }
 
     private static function box($func)
diff --git a/src/Symfony/Component/Filesystem/Tests/FilesystemTest.php b/src/Symfony/Component/Filesystem/Tests/FilesystemTest.php
index def1e5fc09..3fce72059a 100644
--- a/src/Symfony/Component/Filesystem/Tests/FilesystemTest.php
+++ b/src/Symfony/Component/Filesystem/Tests/FilesystemTest.php
@@ -383,7 +383,7 @@ class FilesystemTest extends FilesystemTestCase
         $oldPath = getcwd();
         mkdir($basePath);
         chdir($basePath);
-        $file = str_repeat('T', $maxPathLength - strlen($basePath) + 1);
+        $file = str_repeat('T', $maxPathLength - \strlen($basePath) + 1);
         $path = $basePath.$file;
         exec('TYPE NUL >>'.$file); // equivalent of touch, we can not use the php touch() here because it suffers from the same limitation
         $this->longPathNamesWindows[] = $path; // save this so we can clean up later
diff --git a/src/Symfony/Component/Filesystem/Tests/FilesystemTestCase.php b/src/Symfony/Component/Filesystem/Tests/FilesystemTestCase.php
index cde01e50eb..8b6b436148 100644
--- a/src/Symfony/Component/Filesystem/Tests/FilesystemTestCase.php
+++ b/src/Symfony/Component/Filesystem/Tests/FilesystemTestCase.php
@@ -48,7 +48,7 @@ class FilesystemTestCase extends TestCase
             $targetFile = tempnam(sys_get_temp_dir(), 'li');
             if (true !== @link($originFile, $targetFile)) {
                 $report = error_get_last();
-                if (is_array($report) && false !== strpos($report['message'], 'error code(1314)')) {
+                if (\is_array($report) && false !== strpos($report['message'], 'error code(1314)')) {
                     self::$linkOnWindows = false;
                 }
             } else {
@@ -60,7 +60,7 @@ class FilesystemTestCase extends TestCase
             $targetDir = tempnam(sys_get_temp_dir(), 'sl');
             if (true !== @symlink($originDir, $targetDir)) {
                 $report = error_get_last();
-                if (is_array($report) && false !== strpos($report['message'], 'error code(1314)')) {
+                if (\is_array($report) && false !== strpos($report['message'], 'error code(1314)')) {
                     self::$symlinkOnWindows = false;
                 }
             } else {
@@ -129,7 +129,7 @@ class FilesystemTestCase extends TestCase
 
     protected function markAsSkippedIfLinkIsMissing()
     {
-        if (!function_exists('link')) {
+        if (!\function_exists('link')) {
             $this->markTestSkipped('link is not supported');
         }
 
@@ -159,7 +159,7 @@ class FilesystemTestCase extends TestCase
 
     protected function markAsSkippedIfPosixIsMissing()
     {
-        if (!function_exists('posix_isatty')) {
+        if (!\function_exists('posix_isatty')) {
             $this->markTestSkipped('Function posix_isatty is required.');
         }
     }
diff --git a/src/Symfony/Component/Finder/Comparator/Comparator.php b/src/Symfony/Component/Finder/Comparator/Comparator.php
index 4f5e1ffe12..ea37566df8 100644
--- a/src/Symfony/Component/Finder/Comparator/Comparator.php
+++ b/src/Symfony/Component/Finder/Comparator/Comparator.php
@@ -64,7 +64,7 @@ class Comparator
             $operator = '==';
         }
 
-        if (!in_array($operator, array('>', '<', '>=', '<=', '==', '!='))) {
+        if (!\in_array($operator, array('>', '<', '>=', '<=', '==', '!='))) {
             throw new \InvalidArgumentException(sprintf('Invalid operator "%s".', $operator));
         }
 
diff --git a/src/Symfony/Component/Finder/Finder.php b/src/Symfony/Component/Finder/Finder.php
index a01f7f4e37..b403038d46 100644
--- a/src/Symfony/Component/Finder/Finder.php
+++ b/src/Symfony/Component/Finder/Finder.php
@@ -419,7 +419,7 @@ class Finder implements \IteratorAggregate, \Countable
      */
     public function sortByName(/* bool $useNaturalSort = false */)
     {
-        $useNaturalSort = 0 < func_num_args() && func_get_arg(0);
+        $useNaturalSort = 0 < \func_num_args() && func_get_arg(0);
 
         $this->sort = $useNaturalSort ? Iterator\SortableIterator::SORT_BY_NAME_NATURAL : Iterator\SortableIterator::SORT_BY_NAME;
 
@@ -559,7 +559,7 @@ class Finder implements \IteratorAggregate, \Countable
         foreach ((array) $dirs as $dir) {
             if (is_dir($dir)) {
                 $resolvedDirs[] = $this->normalizeDir($dir);
-            } elseif ($glob = glob($dir, (defined('GLOB_BRACE') ? GLOB_BRACE : 0) | GLOB_ONLYDIR)) {
+            } elseif ($glob = glob($dir, (\defined('GLOB_BRACE') ? GLOB_BRACE : 0) | GLOB_ONLYDIR)) {
                 $resolvedDirs = array_merge($resolvedDirs, array_map(array($this, 'normalizeDir'), $glob));
             } else {
                 throw new \InvalidArgumentException(sprintf('The "%s" directory does not exist.', $dir));
@@ -582,11 +582,11 @@ class Finder implements \IteratorAggregate, \Countable
      */
     public function getIterator()
     {
-        if (0 === count($this->dirs) && 0 === count($this->iterators)) {
+        if (0 === \count($this->dirs) && 0 === \count($this->iterators)) {
             throw new \LogicException('You must call one of in() or append() methods before iterating over a Finder.');
         }
 
-        if (1 === count($this->dirs) && 0 === count($this->iterators)) {
+        if (1 === \count($this->dirs) && 0 === \count($this->iterators)) {
             return $this->searchInDirectory($this->dirs[0]);
         }
 
@@ -619,7 +619,7 @@ class Finder implements \IteratorAggregate, \Countable
             $this->iterators[] = $iterator->getIterator();
         } elseif ($iterator instanceof \Iterator) {
             $this->iterators[] = $iterator;
-        } elseif ($iterator instanceof \Traversable || is_array($iterator)) {
+        } elseif ($iterator instanceof \Traversable || \is_array($iterator)) {
             $it = new \ArrayIterator();
             foreach ($iterator as $file) {
                 $it->append($file instanceof \SplFileInfo ? $file : new \SplFileInfo($file));
diff --git a/src/Symfony/Component/Finder/Glob.php b/src/Symfony/Component/Finder/Glob.php
index df8b86fa5f..d8df62bfea 100644
--- a/src/Symfony/Component/Finder/Glob.php
+++ b/src/Symfony/Component/Finder/Glob.php
@@ -51,7 +51,7 @@ class Glob
         $escaping = false;
         $inCurlies = 0;
         $regex = '';
-        $sizeGlob = strlen($glob);
+        $sizeGlob = \strlen($glob);
         for ($i = 0; $i < $sizeGlob; ++$i) {
             $car = $glob[$i];
             if ($firstByte && $strictLeadingDot && '.' !== $car) {
diff --git a/src/Symfony/Component/Finder/Iterator/CustomFilterIterator.php b/src/Symfony/Component/Finder/Iterator/CustomFilterIterator.php
index 031bc15710..77bd3ac873 100644
--- a/src/Symfony/Component/Finder/Iterator/CustomFilterIterator.php
+++ b/src/Symfony/Component/Finder/Iterator/CustomFilterIterator.php
@@ -32,7 +32,7 @@ class CustomFilterIterator extends \FilterIterator
     public function __construct(\Iterator $iterator, array $filters)
     {
         foreach ($filters as $filter) {
-            if (!is_callable($filter)) {
+            if (!\is_callable($filter)) {
                 throw new \InvalidArgumentException('Invalid PHP callback.');
             }
         }
@@ -51,7 +51,7 @@ class CustomFilterIterator extends \FilterIterator
         $fileinfo = $this->current();
 
         foreach ($this->filters as $filter) {
-            if (false === call_user_func($filter, $fileinfo)) {
+            if (false === \call_user_func($filter, $fileinfo)) {
                 return false;
             }
         }
diff --git a/src/Symfony/Component/Finder/Iterator/SortableIterator.php b/src/Symfony/Component/Finder/Iterator/SortableIterator.php
index 4734a6ebdc..00cbab6ee9 100644
--- a/src/Symfony/Component/Finder/Iterator/SortableIterator.php
+++ b/src/Symfony/Component/Finder/Iterator/SortableIterator.php
@@ -68,7 +68,7 @@ class SortableIterator implements \IteratorAggregate
             $this->sort = function ($a, $b) {
                 return $a->getMTime() - $b->getMTime();
             };
-        } elseif (is_callable($sort)) {
+        } elseif (\is_callable($sort)) {
             $this->sort = $sort;
         } else {
             throw new \InvalidArgumentException('The SortableIterator takes a PHP callable or a valid built-in sort algorithm as an argument.');
diff --git a/src/Symfony/Component/Finder/Tests/FinderTest.php b/src/Symfony/Component/Finder/Tests/FinderTest.php
index 35a71acffe..918f5b76d9 100644
--- a/src/Symfony/Component/Finder/Tests/FinderTest.php
+++ b/src/Symfony/Component/Finder/Tests/FinderTest.php
@@ -919,7 +919,7 @@ class FinderTest extends Iterator\RealIteratorTestCase
     public function testCountWithoutIn()
     {
         $finder = Finder::create()->files();
-        count($finder);
+        \count($finder);
     }
 
     public function testHasResults()
diff --git a/src/Symfony/Component/Finder/Tests/GlobTest.php b/src/Symfony/Component/Finder/Tests/GlobTest.php
index d48ac1fc54..a58d15c7dc 100644
--- a/src/Symfony/Component/Finder/Tests/GlobTest.php
+++ b/src/Symfony/Component/Finder/Tests/GlobTest.php
@@ -33,8 +33,8 @@ class GlobTest extends TestCase
 
         foreach ($finder->in(__DIR__) as $k => $v) {
             $k = str_replace(DIRECTORY_SEPARATOR, '/', $k);
-            if (preg_match($regex, substr($k, strlen(__DIR__)))) {
-                $match[] = substr($k, 10 + strlen(__DIR__));
+            if (preg_match($regex, substr($k, \strlen(__DIR__)))) {
+                $match[] = substr($k, 10 + \strlen(__DIR__));
             }
         }
         sort($match);
@@ -50,8 +50,8 @@ class GlobTest extends TestCase
 
         foreach ($finder->in(__DIR__) as $k => $v) {
             $k = str_replace(DIRECTORY_SEPARATOR, '/', $k);
-            if (preg_match($regex, substr($k, strlen(__DIR__)))) {
-                $match[] = substr($k, 10 + strlen(__DIR__));
+            if (preg_match($regex, substr($k, \strlen(__DIR__)))) {
+                $match[] = substr($k, 10 + \strlen(__DIR__));
             }
         }
         sort($match);
@@ -67,8 +67,8 @@ class GlobTest extends TestCase
 
         foreach ($finder->in(__DIR__) as $k => $v) {
             $k = str_replace(DIRECTORY_SEPARATOR, '/', $k);
-            if (preg_match($regex, substr($k, strlen(__DIR__)))) {
-                $match[] = substr($k, 10 + strlen(__DIR__));
+            if (preg_match($regex, substr($k, \strlen(__DIR__)))) {
+                $match[] = substr($k, 10 + \strlen(__DIR__));
             }
         }
         sort($match);
@@ -84,8 +84,8 @@ class GlobTest extends TestCase
 
         foreach ($finder->in(__DIR__) as $k => $v) {
             $k = str_replace(DIRECTORY_SEPARATOR, '/', $k);
-            if (preg_match($regex, substr($k, strlen(__DIR__)))) {
-                $match[] = substr($k, 10 + strlen(__DIR__));
+            if (preg_match($regex, substr($k, \strlen(__DIR__)))) {
+                $match[] = substr($k, 10 + \strlen(__DIR__));
             }
         }
         sort($match);
diff --git a/src/Symfony/Component/Finder/Tests/Iterator/IteratorTestCase.php b/src/Symfony/Component/Finder/Tests/Iterator/IteratorTestCase.php
index c724a75c69..54606b91dd 100644
--- a/src/Symfony/Component/Finder/Tests/Iterator/IteratorTestCase.php
+++ b/src/Symfony/Component/Finder/Tests/Iterator/IteratorTestCase.php
@@ -52,7 +52,7 @@ abstract class IteratorTestCase extends TestCase
 
         foreach ($expected as $subarray) {
             $temp = array();
-            while (count($values) && count($temp) < count($subarray)) {
+            while (\count($values) && \count($temp) < \count($subarray)) {
                 $temp[] = array_shift($values);
             }
             sort($temp);
diff --git a/src/Symfony/Component/Finder/Tests/Iterator/MockSplFileInfo.php b/src/Symfony/Component/Finder/Tests/Iterator/MockSplFileInfo.php
index cfe31c90f7..36e6528d01 100644
--- a/src/Symfony/Component/Finder/Tests/Iterator/MockSplFileInfo.php
+++ b/src/Symfony/Component/Finder/Tests/Iterator/MockSplFileInfo.php
@@ -25,9 +25,9 @@ class MockSplFileInfo extends \SplFileInfo
 
     public function __construct($param)
     {
-        if (is_string($param)) {
+        if (\is_string($param)) {
             parent::__construct($param);
-        } elseif (is_array($param)) {
+        } elseif (\is_array($param)) {
             $defaults = array(
               'name' => 'file.txt',
               'contents' => null,
@@ -92,7 +92,7 @@ class MockSplFileInfo extends \SplFileInfo
 
     public function setType($type)
     {
-        if (is_string($type)) {
+        if (\is_string($type)) {
             switch ($type) {
                 case 'directory':
                 case 'd':
diff --git a/src/Symfony/Component/Finder/Tests/Iterator/RealIteratorTestCase.php b/src/Symfony/Component/Finder/Tests/Iterator/RealIteratorTestCase.php
index cf8c58fb13..55b98f38f7 100644
--- a/src/Symfony/Component/Finder/Tests/Iterator/RealIteratorTestCase.php
+++ b/src/Symfony/Component/Finder/Tests/Iterator/RealIteratorTestCase.php
@@ -53,7 +53,7 @@ abstract class RealIteratorTestCase extends IteratorTestCase
         }
 
         foreach (self::$files as $file) {
-            if (DIRECTORY_SEPARATOR === $file[strlen($file) - 1]) {
+            if (DIRECTORY_SEPARATOR === $file[\strlen($file) - 1]) {
                 mkdir($file);
             } else {
                 touch($file);
@@ -96,10 +96,10 @@ abstract class RealIteratorTestCase extends IteratorTestCase
             self::$tmpDir = realpath(sys_get_temp_dir()).DIRECTORY_SEPARATOR.'symfony_finder';
         }
 
-        if (is_array($files)) {
+        if (\is_array($files)) {
             $f = array();
             foreach ($files as $file) {
-                if (is_array($file)) {
+                if (\is_array($file)) {
                     $f[] = self::toAbsolute($file);
                 } else {
                     $f[] = self::$tmpDir.DIRECTORY_SEPARATOR.str_replace('/', DIRECTORY_SEPARATOR, $file);
@@ -109,7 +109,7 @@ abstract class RealIteratorTestCase extends IteratorTestCase
             return $f;
         }
 
-        if (is_string($files)) {
+        if (\is_string($files)) {
             return self::$tmpDir.DIRECTORY_SEPARATOR.str_replace('/', DIRECTORY_SEPARATOR, $files);
         }
 
diff --git a/src/Symfony/Component/Finder/Tests/Iterator/SortableIteratorTest.php b/src/Symfony/Component/Finder/Tests/Iterator/SortableIteratorTest.php
index 9428013a4f..10f01135a4 100644
--- a/src/Symfony/Component/Finder/Tests/Iterator/SortableIteratorTest.php
+++ b/src/Symfony/Component/Finder/Tests/Iterator/SortableIteratorTest.php
@@ -30,7 +30,7 @@ class SortableIteratorTest extends RealIteratorTestCase
      */
     public function testAccept($mode, $expected)
     {
-        if (!is_callable($mode)) {
+        if (!\is_callable($mode)) {
             switch ($mode) {
                 case SortableIterator::SORT_BY_ACCESSED_TIME:
                     if ('\\' === DIRECTORY_SEPARATOR) {
diff --git a/src/Symfony/Component/Form/AbstractExtension.php b/src/Symfony/Component/Form/AbstractExtension.php
index 59710ca226..61497aba6b 100644
--- a/src/Symfony/Component/Form/AbstractExtension.php
+++ b/src/Symfony/Component/Form/AbstractExtension.php
@@ -98,7 +98,7 @@ abstract class AbstractExtension implements FormExtensionInterface
             $this->initTypeExtensions();
         }
 
-        return isset($this->typeExtensions[$name]) && count($this->typeExtensions[$name]) > 0;
+        return isset($this->typeExtensions[$name]) && \count($this->typeExtensions[$name]) > 0;
     }
 
     /**
@@ -156,7 +156,7 @@ abstract class AbstractExtension implements FormExtensionInterface
                 throw new UnexpectedTypeException($type, 'Symfony\Component\Form\FormTypeInterface');
             }
 
-            $this->types[get_class($type)] = $type;
+            $this->types[\get_class($type)] = $type;
         }
     }
 
diff --git a/src/Symfony/Component/Form/AbstractRendererEngine.php b/src/Symfony/Component/Form/AbstractRendererEngine.php
index c6f14c4b9a..7a419dcaea 100644
--- a/src/Symfony/Component/Form/AbstractRendererEngine.php
+++ b/src/Symfony/Component/Form/AbstractRendererEngine.php
@@ -49,7 +49,7 @@ abstract class AbstractRendererEngine implements FormRendererEngineInterface
         $cacheKey = $view->vars[self::CACHE_KEY_VAR];
 
         // Do not cast, as casting turns objects into arrays of properties
-        $this->themes[$cacheKey] = is_array($themes) ? $themes : array($themes);
+        $this->themes[$cacheKey] = \is_array($themes) ? $themes : array($themes);
         $this->useDefaultThemes[$cacheKey] = (bool) $useDefaultThemes;
 
         // Unset instead of resetting to an empty array, in order to allow
diff --git a/src/Symfony/Component/Form/AbstractType.php b/src/Symfony/Component/Form/AbstractType.php
index e99f1073b1..3509db5d94 100644
--- a/src/Symfony/Component/Form/AbstractType.php
+++ b/src/Symfony/Component/Form/AbstractType.php
@@ -52,7 +52,7 @@ abstract class AbstractType implements FormTypeInterface
      */
     public function getBlockPrefix()
     {
-        return StringUtil::fqcnToBlockPrefix(get_class($this));
+        return StringUtil::fqcnToBlockPrefix(\get_class($this));
     }
 
     /**
diff --git a/src/Symfony/Component/Form/CallbackTransformer.php b/src/Symfony/Component/Form/CallbackTransformer.php
index 5a0574ac82..0a59d29721 100644
--- a/src/Symfony/Component/Form/CallbackTransformer.php
+++ b/src/Symfony/Component/Form/CallbackTransformer.php
@@ -41,7 +41,7 @@ class CallbackTransformer implements DataTransformerInterface
      */
     public function transform($data)
     {
-        return call_user_func($this->transform, $data);
+        return \call_user_func($this->transform, $data);
     }
 
     /**
@@ -57,6 +57,6 @@ class CallbackTransformer implements DataTransformerInterface
      */
     public function reverseTransform($data)
     {
-        return call_user_func($this->reverseTransform, $data);
+        return \call_user_func($this->reverseTransform, $data);
     }
 }
diff --git a/src/Symfony/Component/Form/ChoiceList/ArrayChoiceList.php b/src/Symfony/Component/Form/ChoiceList/ArrayChoiceList.php
index 5ae457b245..db18f68112 100644
--- a/src/Symfony/Component/Form/ChoiceList/ArrayChoiceList.php
+++ b/src/Symfony/Component/Form/ChoiceList/ArrayChoiceList.php
@@ -155,7 +155,7 @@ class ArrayChoiceList implements ChoiceListInterface
             $givenValues = array();
 
             foreach ($choices as $i => $givenChoice) {
-                $givenValues[$i] = (string) call_user_func($this->valueCallback, $givenChoice);
+                $givenValues[$i] = (string) \call_user_func($this->valueCallback, $givenChoice);
             }
 
             return array_intersect($givenValues, array_keys($this->choices));
@@ -196,13 +196,13 @@ class ArrayChoiceList implements ChoiceListInterface
         }
 
         foreach ($choices as $key => $choice) {
-            if (is_array($choice)) {
+            if (\is_array($choice)) {
                 $this->flatten($choice, $value, $choicesByValues, $keysByValues, $structuredValues[$key]);
 
                 continue;
             }
 
-            $choiceValue = (string) call_user_func($value, $choice);
+            $choiceValue = (string) \call_user_func($value, $choice);
             $choicesByValues[$choiceValue] = $choice;
             $keysByValues[$choiceValue] = $key;
             $structuredValues[$key] = $choiceValue;
@@ -222,7 +222,7 @@ class ArrayChoiceList implements ChoiceListInterface
     private function castableToString(array $choices, array &$cache = array())
     {
         foreach ($choices as $choice) {
-            if (is_array($choice)) {
+            if (\is_array($choice)) {
                 if (!$this->castableToString($choice, $cache)) {
                     return false;
                 }
diff --git a/src/Symfony/Component/Form/ChoiceList/Factory/CachingFactoryDecorator.php b/src/Symfony/Component/Form/ChoiceList/Factory/CachingFactoryDecorator.php
index 1e571ed81c..dba025bc64 100644
--- a/src/Symfony/Component/Form/ChoiceList/Factory/CachingFactoryDecorator.php
+++ b/src/Symfony/Component/Form/ChoiceList/Factory/CachingFactoryDecorator.php
@@ -49,11 +49,11 @@ class CachingFactoryDecorator implements ChoiceListFactoryInterface
      */
     public static function generateHash($value, $namespace = '')
     {
-        if (is_object($value)) {
+        if (\is_object($value)) {
             $value = spl_object_hash($value);
-        } elseif (is_array($value)) {
+        } elseif (\is_array($value)) {
             array_walk_recursive($value, function (&$v) {
-                if (is_object($v)) {
+                if (\is_object($v)) {
                     $v = spl_object_hash($v);
                 }
             });
@@ -77,7 +77,7 @@ class CachingFactoryDecorator implements ChoiceListFactoryInterface
         }
 
         foreach ($array as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 self::flatten($value, $output);
                 continue;
             }
diff --git a/src/Symfony/Component/Form/ChoiceList/Factory/DefaultChoiceListFactory.php b/src/Symfony/Component/Form/ChoiceList/Factory/DefaultChoiceListFactory.php
index 8d28376fd1..5dfe8fcd4d 100644
--- a/src/Symfony/Component/Form/ChoiceList/Factory/DefaultChoiceListFactory.php
+++ b/src/Symfony/Component/Form/ChoiceList/Factory/DefaultChoiceListFactory.php
@@ -52,9 +52,9 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
         $choices = $list->getChoices();
         $keys = $list->getOriginalKeys();
 
-        if (!is_callable($preferredChoices) && !empty($preferredChoices)) {
+        if (!\is_callable($preferredChoices) && !empty($preferredChoices)) {
             $preferredChoices = function ($choice) use ($preferredChoices) {
-                return in_array($choice, $preferredChoices, true);
+                return \in_array($choice, $preferredChoices, true);
             };
         }
 
@@ -66,7 +66,7 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
         // If $groupBy is a callable, choices are added to the group with the
         // name returned by the callable. If the callable returns null, the
         // choice is not added to any group
-        if (is_callable($groupBy)) {
+        if (\is_callable($groupBy)) {
             foreach ($choices as $value => $choice) {
                 self::addChoiceViewGroupedBy(
                     $groupBy,
@@ -99,13 +99,13 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
         // Remove any empty group view that may have been created by
         // addChoiceViewGroupedBy()
         foreach ($preferredViews as $key => $view) {
-            if ($view instanceof ChoiceGroupView && 0 === count($view->choices)) {
+            if ($view instanceof ChoiceGroupView && 0 === \count($view->choices)) {
                 unset($preferredViews[$key]);
             }
         }
 
         foreach ($otherViews as $key => $view) {
-            if ($view instanceof ChoiceGroupView && 0 === count($view->choices)) {
+            if ($view instanceof ChoiceGroupView && 0 === \count($view->choices)) {
                 unset($otherViews[$key]);
             }
         }
@@ -118,7 +118,7 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
         // $value may be an integer or a string, since it's stored in the array
         // keys. We want to guarantee it's a string though.
         $key = $keys[$value];
-        $nextIndex = is_int($index) ? $index++ : call_user_func($index, $choice, $key, $value);
+        $nextIndex = \is_int($index) ? $index++ : \call_user_func($index, $choice, $key, $value);
 
         // BC normalize label to accept a false value
         if (null === $label) {
@@ -127,7 +127,7 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
         } elseif (false !== $label) {
             // If "choice_label" is set to false and "expanded" is true, the value false
             // should be passed on to the "label" option of the checkboxes/radio buttons
-            $dynamicLabel = call_user_func($label, $choice, $key, $value);
+            $dynamicLabel = \call_user_func($label, $choice, $key, $value);
             $label = false === $dynamicLabel ? false : (string) $dynamicLabel;
         }
 
@@ -137,11 +137,11 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
             $label,
             // The attributes may be a callable or a mapping from choice indices
             // to nested arrays
-            is_callable($attr) ? call_user_func($attr, $choice, $key, $value) : (isset($attr[$key]) ? $attr[$key] : array())
+            \is_callable($attr) ? \call_user_func($attr, $choice, $key, $value) : (isset($attr[$key]) ? $attr[$key] : array())
         );
 
         // $isPreferred may be null if no choices are preferred
-        if ($isPreferred && call_user_func($isPreferred, $choice, $key, $value)) {
+        if ($isPreferred && \call_user_func($isPreferred, $choice, $key, $value)) {
             $preferredViews[$nextIndex] = $view;
         } else {
             $otherViews[$nextIndex] = $view;
@@ -156,7 +156,7 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
             }
 
             // Add the contents of groups to new ChoiceGroupView instances
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $preferredViewsForGroup = array();
                 $otherViewsForGroup = array();
 
@@ -172,11 +172,11 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
                     $otherViewsForGroup
                 );
 
-                if (count($preferredViewsForGroup) > 0) {
+                if (\count($preferredViewsForGroup) > 0) {
                     $preferredViews[$key] = new ChoiceGroupView($key, $preferredViewsForGroup);
                 }
 
-                if (count($otherViewsForGroup) > 0) {
+                if (\count($otherViewsForGroup) > 0) {
                     $otherViews[$key] = new ChoiceGroupView($key, $otherViewsForGroup);
                 }
 
@@ -200,7 +200,7 @@ class DefaultChoiceListFactory implements ChoiceListFactoryInterface
 
     private static function addChoiceViewGroupedBy($groupBy, $choice, $value, $label, $keys, &$index, $attr, $isPreferred, &$preferredViews, &$otherViews)
     {
-        $groupLabel = call_user_func($groupBy, $choice, $keys[$value], $value);
+        $groupLabel = \call_user_func($groupBy, $choice, $keys[$value], $value);
 
         if (null === $groupLabel) {
             // If the callable returns null, don't group the choice
diff --git a/src/Symfony/Component/Form/ChoiceList/Factory/PropertyAccessDecorator.php b/src/Symfony/Component/Form/ChoiceList/Factory/PropertyAccessDecorator.php
index 8584c91170..8d8e10da1f 100644
--- a/src/Symfony/Component/Form/ChoiceList/Factory/PropertyAccessDecorator.php
+++ b/src/Symfony/Component/Form/ChoiceList/Factory/PropertyAccessDecorator.php
@@ -71,7 +71,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
      */
     public function createListFromChoices($choices, $value = null)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             $value = new PropertyPath($value);
         }
 
@@ -82,7 +82,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
                 // when such values are passed to
                 // ChoiceListInterface::getValuesForChoices(). Handle this case
                 // so that the call to getValue() doesn't break.
-                if (is_object($choice) || is_array($choice)) {
+                if (\is_object($choice) || \is_array($choice)) {
                     return $accessor->getValue($choice, $value);
                 }
             };
@@ -102,7 +102,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
      */
     public function createListFromLoader(ChoiceLoaderInterface $loader, $value = null)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             $value = new PropertyPath($value);
         }
 
@@ -113,7 +113,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
                 // when such values are passed to
                 // ChoiceListInterface::getValuesForChoices(). Handle this case
                 // so that the call to getValue() doesn't break.
-                if (is_object($choice) || is_array($choice)) {
+                if (\is_object($choice) || \is_array($choice)) {
                     return $accessor->getValue($choice, $value);
                 }
             };
@@ -138,7 +138,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
     {
         $accessor = $this->propertyAccessor;
 
-        if (is_string($label)) {
+        if (\is_string($label)) {
             $label = new PropertyPath($label);
         }
 
@@ -148,7 +148,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
             };
         }
 
-        if (is_string($preferredChoices)) {
+        if (\is_string($preferredChoices)) {
             $preferredChoices = new PropertyPath($preferredChoices);
         }
 
@@ -163,7 +163,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
             };
         }
 
-        if (is_string($index)) {
+        if (\is_string($index)) {
             $index = new PropertyPath($index);
         }
 
@@ -173,7 +173,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
             };
         }
 
-        if (is_string($groupBy)) {
+        if (\is_string($groupBy)) {
             $groupBy = new PropertyPath($groupBy);
         }
 
@@ -187,7 +187,7 @@ class PropertyAccessDecorator implements ChoiceListFactoryInterface
             };
         }
 
-        if (is_string($attr)) {
+        if (\is_string($attr)) {
             $attr = new PropertyPath($attr);
         }
 
diff --git a/src/Symfony/Component/Form/ChoiceList/Loader/CallbackChoiceLoader.php b/src/Symfony/Component/Form/ChoiceList/Loader/CallbackChoiceLoader.php
index d2ca5e013c..b2825051af 100644
--- a/src/Symfony/Component/Form/ChoiceList/Loader/CallbackChoiceLoader.php
+++ b/src/Symfony/Component/Form/ChoiceList/Loader/CallbackChoiceLoader.php
@@ -46,7 +46,7 @@ class CallbackChoiceLoader implements ChoiceLoaderInterface
             return $this->choiceList;
         }
 
-        return $this->choiceList = new ArrayChoiceList(call_user_func($this->callback), $value);
+        return $this->choiceList = new ArrayChoiceList(\call_user_func($this->callback), $value);
     }
 
     /**
diff --git a/src/Symfony/Component/Form/Command/DebugCommand.php b/src/Symfony/Component/Form/Command/DebugCommand.php
index 68f3bc96f1..7ad84d8701 100644
--- a/src/Symfony/Component/Form/Command/DebugCommand.php
+++ b/src/Symfony/Component/Form/Command/DebugCommand.php
@@ -111,10 +111,10 @@ EOF
                 $object = $resolvedType->getOptionsResolver();
 
                 if (!$object->isDefined($option)) {
-                    $message = sprintf('Option "%s" is not defined in "%s".', $option, get_class($resolvedType->getInnerType()));
+                    $message = sprintf('Option "%s" is not defined in "%s".', $option, \get_class($resolvedType->getInnerType()));
 
                     if ($alternatives = $this->findAlternatives($option, $object->getDefinedOptions())) {
-                        if (1 == count($alternatives)) {
+                        if (1 == \count($alternatives)) {
                             $message .= "\n\nDid you mean this?\n    ";
                         } else {
                             $message .= "\n\nDid you mean one of these?\n    ";
@@ -147,12 +147,12 @@ EOF
             }
         }
 
-        if (0 === $count = count($classes)) {
+        if (0 === $count = \count($classes)) {
             $message = sprintf("Could not find type \"%s\" into the following namespaces:\n    %s", $shortClassName, implode("\n    ", $this->namespaces));
 
             $allTypes = array_merge($this->getCoreTypes(), $this->types);
             if ($alternatives = $this->findAlternatives($shortClassName, $allTypes)) {
-                if (1 == count($alternatives)) {
+                if (1 == \count($alternatives)) {
                     $message .= "\n\nDid you mean this?\n    ";
                 } else {
                     $message .= "\n\nDid you mean one of these?\n    ";
@@ -178,7 +178,7 @@ EOF
         $loadTypesRefMethod = (new \ReflectionObject($coreExtension))->getMethod('loadTypes');
         $loadTypesRefMethod->setAccessible(true);
         $coreTypes = $loadTypesRefMethod->invoke($coreExtension);
-        $coreTypes = array_map(function (FormTypeInterface $type) { return get_class($type); }, $coreTypes);
+        $coreTypes = array_map(function (FormTypeInterface $type) { return \get_class($type); }, $coreTypes);
         sort($coreTypes);
 
         return $coreTypes;
@@ -189,7 +189,7 @@ EOF
         $alternatives = array();
         foreach ($collection as $item) {
             $lev = levenshtein($name, $item);
-            if ($lev <= strlen($name) / 3 || false !== strpos($item, $name)) {
+            if ($lev <= \strlen($name) / 3 || false !== strpos($item, $name)) {
                 $alternatives[$item] = isset($alternatives[$item]) ? $alternatives[$item] - $lev : $lev;
             }
         }
diff --git a/src/Symfony/Component/Form/Console/Descriptor/Descriptor.php b/src/Symfony/Component/Form/Console/Descriptor/Descriptor.php
index fbdb19aff6..bfa4302da2 100644
--- a/src/Symfony/Component/Form/Console/Descriptor/Descriptor.php
+++ b/src/Symfony/Component/Form/Console/Descriptor/Descriptor.php
@@ -58,7 +58,7 @@ abstract class Descriptor implements DescriptorInterface
                 $this->describeOption($object, $options);
                 break;
             default:
-                throw new \InvalidArgumentException(sprintf('Object of type "%s" is not describable.', get_class($object)));
+                throw new \InvalidArgumentException(sprintf('Object of type "%s" is not describable.', \get_class($object)));
         }
     }
 
@@ -133,7 +133,7 @@ abstract class Descriptor implements DescriptorInterface
 
     private function getParentOptionsResolver(ResolvedFormTypeInterface $type)
     {
-        $this->parents[$class = get_class($type->getInnerType())] = array();
+        $this->parents[$class = \get_class($type->getInnerType())] = array();
 
         if (null !== $type->getParent()) {
             $optionsResolver = clone $this->getParentOptionsResolver($type->getParent());
@@ -155,7 +155,7 @@ abstract class Descriptor implements DescriptorInterface
         foreach ($type->getTypeExtensions() as $extension) {
             $inheritedOptions = $optionsResolver->getDefinedOptions();
             $extension->configureOptions($optionsResolver);
-            $this->extensions[get_class($extension)] = array_diff($optionsResolver->getDefinedOptions(), $inheritedOptions);
+            $this->extensions[\get_class($extension)] = array_diff($optionsResolver->getDefinedOptions(), $inheritedOptions);
         }
     }
 }
diff --git a/src/Symfony/Component/Form/Console/Descriptor/JsonDescriptor.php b/src/Symfony/Component/Form/Console/Descriptor/JsonDescriptor.php
index 9d02aba3c1..8e5a03e9ca 100644
--- a/src/Symfony/Component/Form/Console/Descriptor/JsonDescriptor.php
+++ b/src/Symfony/Component/Form/Console/Descriptor/JsonDescriptor.php
@@ -45,7 +45,7 @@ class JsonDescriptor extends Descriptor
         $this->sortOptions($formOptions);
 
         $data = array(
-            'class' => get_class($resolvedFormType->getInnerType()),
+            'class' => \get_class($resolvedFormType->getInnerType()),
             'block_prefix' => $resolvedFormType->getInnerType()->getBlockPrefix(),
             'options' => $formOptions,
             'parent_types' => $this->parents,
@@ -90,7 +90,7 @@ class JsonDescriptor extends Descriptor
         foreach ($options as &$opts) {
             $sorted = false;
             foreach ($opts as &$opt) {
-                if (is_array($opt)) {
+                if (\is_array($opt)) {
                     sort($opt);
                     $sorted = true;
                 }
diff --git a/src/Symfony/Component/Form/Console/Descriptor/TextDescriptor.php b/src/Symfony/Component/Form/Console/Descriptor/TextDescriptor.php
index d899ffce4e..ac8a8bb232 100644
--- a/src/Symfony/Component/Form/Console/Descriptor/TextDescriptor.php
+++ b/src/Symfony/Component/Form/Console/Descriptor/TextDescriptor.php
@@ -28,9 +28,9 @@ class TextDescriptor extends Descriptor
     protected function describeDefaults(array $options)
     {
         $this->output->section('Built-in form types (Symfony\Component\Form\Extension\Core\Type)');
-        $shortClassNames = array_map(function ($fqcn) { return array_slice(explode('\\', $fqcn), -1)[0]; }, $options['core_types']);
-        for ($i = 0; $i * 5 < count($shortClassNames); ++$i) {
-            $this->output->writeln(' '.implode(', ', array_slice($shortClassNames, $i * 5, 5)));
+        $shortClassNames = array_map(function ($fqcn) { return \array_slice(explode('\\', $fqcn), -1)[0]; }, $options['core_types']);
+        for ($i = 0; $i * 5 < \count($shortClassNames); ++$i) {
+            $this->output->writeln(' '.implode(', ', \array_slice($shortClassNames, $i * 5, 5)));
         }
 
         $this->output->section('Service form types');
@@ -63,14 +63,14 @@ class TextDescriptor extends Descriptor
         ), $formOptions);
 
         $tableRows = array();
-        $count = count(max($formOptions));
+        $count = \count(max($formOptions));
         for ($i = 0; $i < $count; ++$i) {
             $cells = array();
             foreach (array_keys($tableHeaders) as $group) {
                 if (isset($formOptions[$group][$i])) {
                     $option = $formOptions[$group][$i];
 
-                    if (is_string($option) && in_array($option, $this->requiredOptions)) {
+                    if (\is_string($option) && \in_array($option, $this->requiredOptions)) {
                         $option .= ' <info>(required)</info>';
                     }
 
@@ -82,7 +82,7 @@ class TextDescriptor extends Descriptor
             $tableRows[] = $cells;
         }
 
-        $this->output->title(sprintf('%s (Block prefix: "%s")', get_class($resolvedFormType->getInnerType()), $resolvedFormType->getInnerType()->getBlockPrefix()));
+        $this->output->title(sprintf('%s (Block prefix: "%s")', \get_class($resolvedFormType->getInnerType()), $resolvedFormType->getInnerType()->getBlockPrefix()));
         $this->output->table($tableHeaders, $tableRows);
 
         if ($this->parents) {
@@ -120,7 +120,7 @@ class TextDescriptor extends Descriptor
         }
         array_pop($rows);
 
-        $this->output->title(sprintf('%s (%s)', get_class($options['type']), $options['option']));
+        $this->output->title(sprintf('%s (%s)', \get_class($options['type']), $options['option']));
         $this->output->table(array(), $rows);
     }
 
@@ -129,11 +129,11 @@ class TextDescriptor extends Descriptor
         foreach ($options as $group => $opts) {
             $sorted = false;
             foreach ($opts as $class => $opt) {
-                if (is_string($class)) {
+                if (\is_string($class)) {
                     unset($options[$group][$class]);
                 }
 
-                if (!is_array($opt) || 0 === count($opt)) {
+                if (!\is_array($opt) || 0 === \count($opt)) {
                     continue;
                 }
 
@@ -165,7 +165,7 @@ class TextDescriptor extends Descriptor
             $prefix = Caster::PREFIX_VIRTUAL;
 
             return array(
-                $prefix.'parameters' => isset($a[$prefix.'parameters']) ? count($a[$prefix.'parameters']->value) : 0,
+                $prefix.'parameters' => isset($a[$prefix.'parameters']) ? \count($a[$prefix.'parameters']->value) : 0,
                 $prefix.'file' => $a[$prefix.'file'],
                 $prefix.'line' => $a[$prefix.'line'],
             );
diff --git a/src/Symfony/Component/Form/Exception/UnexpectedTypeException.php b/src/Symfony/Component/Form/Exception/UnexpectedTypeException.php
index 77a5c79d97..c9aa11eb47 100644
--- a/src/Symfony/Component/Form/Exception/UnexpectedTypeException.php
+++ b/src/Symfony/Component/Form/Exception/UnexpectedTypeException.php
@@ -15,6 +15,6 @@ class UnexpectedTypeException extends InvalidArgumentException
 {
     public function __construct($value, string $expectedType)
     {
-        parent::__construct(sprintf('Expected argument of type "%s", "%s" given', $expectedType, is_object($value) ? get_class($value) : gettype($value)));
+        parent::__construct(sprintf('Expected argument of type "%s", "%s" given', $expectedType, \is_object($value) ? \get_class($value) : \gettype($value)));
     }
 }
diff --git a/src/Symfony/Component/Form/Extension/Core/DataMapper/CheckboxListMapper.php b/src/Symfony/Component/Form/Extension/Core/DataMapper/CheckboxListMapper.php
index b85fb0025f..5e21010222 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataMapper/CheckboxListMapper.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataMapper/CheckboxListMapper.php
@@ -34,13 +34,13 @@ class CheckboxListMapper implements DataMapperInterface
             $choices = array();
         }
 
-        if (!is_array($choices)) {
+        if (!\is_array($choices)) {
             throw new UnexpectedTypeException($choices, 'array');
         }
 
         foreach ($checkboxes as $checkbox) {
             $value = $checkbox->getConfig()->getOption('value');
-            $checkbox->setData(in_array($value, $choices, true));
+            $checkbox->setData(\in_array($value, $choices, true));
         }
     }
 
@@ -49,7 +49,7 @@ class CheckboxListMapper implements DataMapperInterface
      */
     public function mapFormsToData($checkboxes, &$choices)
     {
-        if (!is_array($choices)) {
+        if (!\is_array($choices)) {
             throw new UnexpectedTypeException($choices, 'array');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataMapper/PropertyPathMapper.php b/src/Symfony/Component/Form/Extension/Core/DataMapper/PropertyPathMapper.php
index 25aba9a16d..f9721e52b1 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataMapper/PropertyPathMapper.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataMapper/PropertyPathMapper.php
@@ -37,7 +37,7 @@ class PropertyPathMapper implements DataMapperInterface
     {
         $empty = null === $data || array() === $data;
 
-        if (!$empty && !is_array($data) && !is_object($data)) {
+        if (!$empty && !\is_array($data) && !\is_object($data)) {
             throw new UnexpectedTypeException($data, 'object, array or empty');
         }
 
@@ -62,7 +62,7 @@ class PropertyPathMapper implements DataMapperInterface
             return;
         }
 
-        if (!is_array($data) && !is_object($data)) {
+        if (!\is_array($data) && !\is_object($data)) {
             throw new UnexpectedTypeException($data, 'object, array or empty');
         }
 
@@ -81,7 +81,7 @@ class PropertyPathMapper implements DataMapperInterface
 
                 // If the data is identical to the value in $data, we are
                 // dealing with a reference
-                if (!is_object($data) || !$config->getByReference() || $form->getData() !== $this->propertyAccessor->getValue($data, $propertyPath)) {
+                if (!\is_object($data) || !$config->getByReference() || $form->getData() !== $this->propertyAccessor->getValue($data, $propertyPath)) {
                     $this->propertyAccessor->setValue($data, $propertyPath, $form->getData());
                 }
             }
diff --git a/src/Symfony/Component/Form/Extension/Core/DataMapper/RadioListMapper.php b/src/Symfony/Component/Form/Extension/Core/DataMapper/RadioListMapper.php
index 6f757c601f..d2ec810f70 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataMapper/RadioListMapper.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataMapper/RadioListMapper.php
@@ -30,7 +30,7 @@ class RadioListMapper implements DataMapperInterface
      */
     public function mapDataToForms($choice, $radios)
     {
-        if (!is_string($choice)) {
+        if (!\is_string($choice)) {
             throw new UnexpectedTypeException($choice, 'string');
         }
 
@@ -45,7 +45,7 @@ class RadioListMapper implements DataMapperInterface
      */
     public function mapFormsToData($radios, &$choice)
     {
-        if (null !== $choice && !is_string($choice)) {
+        if (null !== $choice && !\is_string($choice)) {
             throw new UnexpectedTypeException($choice, 'null or string');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ArrayToPartsTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ArrayToPartsTransformer.php
index 6929fb8867..53d4deddd3 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ArrayToPartsTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ArrayToPartsTransformer.php
@@ -32,7 +32,7 @@ class ArrayToPartsTransformer implements DataTransformerInterface
             $array = array();
         }
 
-        if (!is_array($array)) {
+        if (!\is_array($array)) {
             throw new TransformationFailedException('Expected an array.');
         }
 
@@ -51,7 +51,7 @@ class ArrayToPartsTransformer implements DataTransformerInterface
 
     public function reverseTransform($array)
     {
-        if (!is_array($array)) {
+        if (!\is_array($array)) {
             throw new TransformationFailedException('Expected an array.');
         }
 
@@ -70,8 +70,8 @@ class ArrayToPartsTransformer implements DataTransformerInterface
             }
         }
 
-        if (count($emptyKeys) > 0) {
-            if (count($emptyKeys) === count($this->partMapping)) {
+        if (\count($emptyKeys) > 0) {
+            if (\count($emptyKeys) === \count($this->partMapping)) {
                 // All parts empty
                 return;
             }
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/BooleanToStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/BooleanToStringTransformer.php
index f72cace119..267aa35554 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/BooleanToStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/BooleanToStringTransformer.php
@@ -35,7 +35,7 @@ class BooleanToStringTransformer implements DataTransformerInterface
     {
         $this->trueValue = $trueValue;
         $this->falseValues = $falseValues;
-        if (in_array($this->trueValue, $this->falseValues, true)) {
+        if (\in_array($this->trueValue, $this->falseValues, true)) {
             throw new InvalidArgumentException('The specified "true" value is contained in the false-values');
         }
     }
@@ -55,7 +55,7 @@ class BooleanToStringTransformer implements DataTransformerInterface
             return;
         }
 
-        if (!is_bool($value)) {
+        if (!\is_bool($value)) {
             throw new TransformationFailedException('Expected a Boolean.');
         }
 
@@ -73,11 +73,11 @@ class BooleanToStringTransformer implements DataTransformerInterface
      */
     public function reverseTransform($value)
     {
-        if (in_array($value, $this->falseValues, true)) {
+        if (\in_array($value, $this->falseValues, true)) {
             return false;
         }
 
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoiceToValueTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoiceToValueTransformer.php
index e8424b9299..3353afe57c 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoiceToValueTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoiceToValueTransformer.php
@@ -34,13 +34,13 @@ class ChoiceToValueTransformer implements DataTransformerInterface
 
     public function reverseTransform($value)
     {
-        if (null !== $value && !is_string($value)) {
+        if (null !== $value && !\is_string($value)) {
             throw new TransformationFailedException('Expected a string or null.');
         }
 
         $choices = $this->choiceList->getChoicesForValues(array((string) $value));
 
-        if (1 !== count($choices)) {
+        if (1 !== \count($choices)) {
             if (null === $value || '' === $value) {
                 return;
             }
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoicesToValuesTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoicesToValuesTransformer.php
index a6b2f3fd58..e0b7bef1ae 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoicesToValuesTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ChoicesToValuesTransformer.php
@@ -38,7 +38,7 @@ class ChoicesToValuesTransformer implements DataTransformerInterface
             return array();
         }
 
-        if (!is_array($array)) {
+        if (!\is_array($array)) {
             throw new TransformationFailedException('Expected an array.');
         }
 
@@ -58,13 +58,13 @@ class ChoicesToValuesTransformer implements DataTransformerInterface
             return array();
         }
 
-        if (!is_array($array)) {
+        if (!\is_array($array)) {
             throw new TransformationFailedException('Expected an array.');
         }
 
         $choices = $this->choiceList->getChoicesForValues($array);
 
-        if (count($choices) !== count($array)) {
+        if (\count($choices) !== \count($array)) {
             throw new TransformationFailedException('Could not find all matching choices for the given values');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DataTransformerChain.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DataTransformerChain.php
index 81ffc7e247..72d1586d49 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DataTransformerChain.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DataTransformerChain.php
@@ -73,7 +73,7 @@ class DataTransformerChain implements DataTransformerInterface
      */
     public function reverseTransform($value)
     {
-        for ($i = count($this->transformers) - 1; $i >= 0; --$i) {
+        for ($i = \count($this->transformers) - 1; $i >= 0; --$i) {
             $value = $this->transformers[$i]->reverseTransform($value);
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToArrayTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToArrayTransformer.php
index 0950af445a..b7f3267b12 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToArrayTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToArrayTransformer.php
@@ -88,7 +88,7 @@ class DateIntervalToArrayTransformer implements DataTransformerInterface
         foreach (self::$availableFields as $field => $char) {
             $result[$field] = $dateInterval->format('%'.($this->pad ? strtoupper($char) : $char));
         }
-        if (in_array('weeks', $this->fields, true)) {
+        if (\in_array('weeks', $this->fields, true)) {
             $result['weeks'] = '0';
             if (isset($result['days']) && (int) $result['days'] >= 7) {
                 $result['weeks'] = (string) floor($result['days'] / 7);
@@ -116,7 +116,7 @@ class DateIntervalToArrayTransformer implements DataTransformerInterface
         if (null === $value) {
             return;
         }
-        if (!is_array($value)) {
+        if (!\is_array($value)) {
             throw new UnexpectedTypeException($value, 'array');
         }
         if ('' === implode('', $value)) {
@@ -128,10 +128,10 @@ class DateIntervalToArrayTransformer implements DataTransformerInterface
                 $emptyFields[] = $field;
             }
         }
-        if (count($emptyFields) > 0) {
+        if (\count($emptyFields) > 0) {
             throw new TransformationFailedException(sprintf('The fields "%s" should not be empty', implode('", "', $emptyFields)));
         }
-        if (isset($value['invert']) && !is_bool($value['invert'])) {
+        if (isset($value['invert']) && !\is_bool($value['invert'])) {
             throw new TransformationFailedException('The value of "invert" must be boolean');
         }
         foreach (self::$availableFields as $field => $char) {
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToStringTransformer.php
index 4aeede8232..1e80dd68f7 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateIntervalToStringTransformer.php
@@ -72,7 +72,7 @@ class DateIntervalToStringTransformer implements DataTransformerInterface
         if (null === $value) {
             return;
         }
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new UnexpectedTypeException($value, 'string');
         }
         if ('' === $value) {
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToArrayTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToArrayTransformer.php
index 8edc501fca..60c39b6f8f 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToArrayTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToArrayTransformer.php
@@ -114,7 +114,7 @@ class DateTimeToArrayTransformer extends BaseDateTimeTransformer
             return;
         }
 
-        if (!is_array($value)) {
+        if (!\is_array($value)) {
             throw new TransformationFailedException('Expected an array.');
         }
 
@@ -130,7 +130,7 @@ class DateTimeToArrayTransformer extends BaseDateTimeTransformer
             }
         }
 
-        if (count($emptyFields) > 0) {
+        if (\count($emptyFields) > 0) {
             throw new TransformationFailedException(
                 sprintf('The fields "%s" should not be empty', implode('", "', $emptyFields)
             ));
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToLocalizedStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToLocalizedStringTransformer.php
index 16b141985e..b97773353c 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToLocalizedStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToLocalizedStringTransformer.php
@@ -51,11 +51,11 @@ class DateTimeToLocalizedStringTransformer extends BaseDateTimeTransformer
             $timeFormat = \IntlDateFormatter::SHORT;
         }
 
-        if (!in_array($dateFormat, self::$formats, true)) {
+        if (!\in_array($dateFormat, self::$formats, true)) {
             throw new UnexpectedTypeException($dateFormat, implode('", "', self::$formats));
         }
 
-        if (!in_array($timeFormat, self::$formats, true)) {
+        if (!\in_array($timeFormat, self::$formats, true)) {
             throw new UnexpectedTypeException($timeFormat, implode('", "', self::$formats));
         }
 
@@ -106,7 +106,7 @@ class DateTimeToLocalizedStringTransformer extends BaseDateTimeTransformer
      */
     public function reverseTransform($value)
     {
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToRfc3339Transformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToRfc3339Transformer.php
index 550ea9b50f..4f3a944361 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToRfc3339Transformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToRfc3339Transformer.php
@@ -60,7 +60,7 @@ class DateTimeToRfc3339Transformer extends BaseDateTimeTransformer
      */
     public function reverseTransform($rfc3339)
     {
-        if (!is_string($rfc3339)) {
+        if (!\is_string($rfc3339)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php
index c93d2c995d..16e776b9ea 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeToStringTransformer.php
@@ -112,7 +112,7 @@ class DateTimeToStringTransformer extends BaseDateTimeTransformer
             return;
         }
 
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeZoneToStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeZoneToStringTransformer.php
index 978a646907..1547499ed5 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeZoneToStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/DateTimeZoneToStringTransformer.php
@@ -38,7 +38,7 @@ class DateTimeZoneToStringTransformer implements DataTransformerInterface
         }
 
         if ($this->multiple) {
-            if (!is_array($dateTimeZone)) {
+            if (!\is_array($dateTimeZone)) {
                 throw new TransformationFailedException('Expected an array.');
             }
 
@@ -62,14 +62,14 @@ class DateTimeZoneToStringTransformer implements DataTransformerInterface
         }
 
         if ($this->multiple) {
-            if (!is_array($value)) {
+            if (!\is_array($value)) {
                 throw new TransformationFailedException('Expected an array.');
             }
 
             return array_map(array(new self(), 'reverseTransform'), $value);
         }
 
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php
index d513caffc7..84df5ba7b6 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/NumberToLocalizedStringTransformer.php
@@ -138,7 +138,7 @@ class NumberToLocalizedStringTransformer implements DataTransformerInterface
      */
     public function reverseTransform($value)
     {
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
@@ -181,7 +181,7 @@ class NumberToLocalizedStringTransformer implements DataTransformerInterface
             throw new TransformationFailedException('I don\'t have a clear idea what infinity looks like');
         }
 
-        if (is_int($result) && $result === (int) $float = (float) $result) {
+        if (\is_int($result) && $result === (int) $float = (float) $result) {
             $result = $float;
         }
 
@@ -189,7 +189,7 @@ class NumberToLocalizedStringTransformer implements DataTransformerInterface
             $length = mb_strlen($value, $encoding);
             $remainder = mb_substr($value, $position, $length, $encoding);
         } else {
-            $length = strlen($value);
+            $length = \strlen($value);
             $remainder = substr($value, $position, $length);
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/PercentToLocalizedStringTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/PercentToLocalizedStringTransformer.php
index 0ac32d5e2f..74439a042c 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/PercentToLocalizedStringTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/PercentToLocalizedStringTransformer.php
@@ -52,7 +52,7 @@ class PercentToLocalizedStringTransformer implements DataTransformerInterface
             $type = self::FRACTIONAL;
         }
 
-        if (!in_array($type, self::$types, true)) {
+        if (!\in_array($type, self::$types, true)) {
             throw new UnexpectedTypeException($type, implode('", "', self::$types));
         }
 
@@ -107,7 +107,7 @@ class PercentToLocalizedStringTransformer implements DataTransformerInterface
      */
     public function reverseTransform($value)
     {
-        if (!is_string($value)) {
+        if (!\is_string($value)) {
             throw new TransformationFailedException('Expected a string.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ValueToDuplicatesTransformer.php b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ValueToDuplicatesTransformer.php
index 5b851af7dd..c9adb0ad5a 100644
--- a/src/Symfony/Component/Form/Extension/Core/DataTransformer/ValueToDuplicatesTransformer.php
+++ b/src/Symfony/Component/Form/Extension/Core/DataTransformer/ValueToDuplicatesTransformer.php
@@ -54,7 +54,7 @@ class ValueToDuplicatesTransformer implements DataTransformerInterface
      */
     public function reverseTransform($array)
     {
-        if (!is_array($array)) {
+        if (!\is_array($array)) {
             throw new TransformationFailedException('Expected an array.');
         }
 
@@ -73,8 +73,8 @@ class ValueToDuplicatesTransformer implements DataTransformerInterface
             }
         }
 
-        if (count($emptyKeys) > 0) {
-            if (count($emptyKeys) == count($this->keys)) {
+        if (\count($emptyKeys) > 0) {
+            if (\count($emptyKeys) == \count($this->keys)) {
                 // All keys empty
                 return;
             }
diff --git a/src/Symfony/Component/Form/Extension/Core/EventListener/FixUrlProtocolListener.php b/src/Symfony/Component/Form/Extension/Core/EventListener/FixUrlProtocolListener.php
index 04ca6647ec..c7c0a46a9f 100644
--- a/src/Symfony/Component/Form/Extension/Core/EventListener/FixUrlProtocolListener.php
+++ b/src/Symfony/Component/Form/Extension/Core/EventListener/FixUrlProtocolListener.php
@@ -36,7 +36,7 @@ class FixUrlProtocolListener implements EventSubscriberInterface
     {
         $data = $event->getData();
 
-        if ($this->defaultProtocol && $data && is_string($data) && !preg_match('~^[\w+.-]+://~', $data)) {
+        if ($this->defaultProtocol && $data && \is_string($data) && !preg_match('~^[\w+.-]+://~', $data)) {
             $event->setData($this->defaultProtocol.'://'.$data);
         }
     }
diff --git a/src/Symfony/Component/Form/Extension/Core/EventListener/MergeCollectionListener.php b/src/Symfony/Component/Form/Extension/Core/EventListener/MergeCollectionListener.php
index 2a99581e75..3649f00537 100644
--- a/src/Symfony/Component/Form/Extension/Core/EventListener/MergeCollectionListener.php
+++ b/src/Symfony/Component/Form/Extension/Core/EventListener/MergeCollectionListener.php
@@ -50,11 +50,11 @@ class MergeCollectionListener implements EventSubscriberInterface
             $data = array();
         }
 
-        if (!is_array($data) && !($data instanceof \Traversable && $data instanceof \ArrayAccess)) {
+        if (!\is_array($data) && !($data instanceof \Traversable && $data instanceof \ArrayAccess)) {
             throw new UnexpectedTypeException($data, 'array or (\Traversable and \ArrayAccess)');
         }
 
-        if (null !== $dataToMergeInto && !is_array($dataToMergeInto) && !($dataToMergeInto instanceof \Traversable && $dataToMergeInto instanceof \ArrayAccess)) {
+        if (null !== $dataToMergeInto && !\is_array($dataToMergeInto) && !($dataToMergeInto instanceof \Traversable && $dataToMergeInto instanceof \ArrayAccess)) {
             throw new UnexpectedTypeException($dataToMergeInto, 'array or (\Traversable and \ArrayAccess)');
         }
 
@@ -72,7 +72,7 @@ class MergeCollectionListener implements EventSubscriberInterface
             }
         } else {
             // Calculate delta
-            $itemsToAdd = is_object($data) ? clone $data : $data;
+            $itemsToAdd = \is_object($data) ? clone $data : $data;
             $itemsToDelete = array();
 
             foreach ($dataToMergeInto as $beforeKey => $beforeItem) {
diff --git a/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php b/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php
index d4b36b921e..2cc97a0421 100644
--- a/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php
+++ b/src/Symfony/Component/Form/Extension/Core/EventListener/ResizeFormListener.php
@@ -66,7 +66,7 @@ class ResizeFormListener implements EventSubscriberInterface
             $data = array();
         }
 
-        if (!is_array($data) && !($data instanceof \Traversable && $data instanceof \ArrayAccess)) {
+        if (!\is_array($data) && !($data instanceof \Traversable && $data instanceof \ArrayAccess)) {
             throw new UnexpectedTypeException($data, 'array or (\Traversable and \ArrayAccess)');
         }
 
@@ -88,7 +88,7 @@ class ResizeFormListener implements EventSubscriberInterface
         $form = $event->getForm();
         $data = $event->getData();
 
-        if (!is_array($data)) {
+        if (!\is_array($data)) {
             $data = array();
         }
 
@@ -126,7 +126,7 @@ class ResizeFormListener implements EventSubscriberInterface
             $data = array();
         }
 
-        if (!is_array($data) && !($data instanceof \Traversable && $data instanceof \ArrayAccess)) {
+        if (!\is_array($data) && !($data instanceof \Traversable && $data instanceof \ArrayAccess)) {
             throw new UnexpectedTypeException($data, 'array or (\Traversable and \ArrayAccess)');
         }
 
@@ -135,7 +135,7 @@ class ResizeFormListener implements EventSubscriberInterface
             /** @var FormInterface $child */
             foreach ($form as $name => $child) {
                 $isNew = !isset($previousData[$name]);
-                $isEmpty = is_callable($this->deleteEmpty) ? call_user_func($this->deleteEmpty, $child->getData()) : $child->isEmpty();
+                $isEmpty = \is_callable($this->deleteEmpty) ? \call_user_func($this->deleteEmpty, $child->getData()) : $child->isEmpty();
 
                 // $isNew can only be true if allowAdd is true, so we don't
                 // need to check allowAdd again
diff --git a/src/Symfony/Component/Form/Extension/Core/EventListener/TrimListener.php b/src/Symfony/Component/Form/Extension/Core/EventListener/TrimListener.php
index 96a1b2dcd6..4b4cc860d4 100644
--- a/src/Symfony/Component/Form/Extension/Core/EventListener/TrimListener.php
+++ b/src/Symfony/Component/Form/Extension/Core/EventListener/TrimListener.php
@@ -27,7 +27,7 @@ class TrimListener implements EventSubscriberInterface
     {
         $data = $event->getData();
 
-        if (!is_string($data)) {
+        if (!\is_string($data)) {
             return;
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/ChoiceType.php b/src/Symfony/Component/Form/Extension/Core/Type/ChoiceType.php
index f4590b29a4..3c4755a6c7 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/ChoiceType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/ChoiceType.php
@@ -70,7 +70,7 @@ class ChoiceType extends AbstractType
 
             // Check if the choices already contain the empty value
             // Only add the placeholder option if this is not the case
-            if (null !== $options['placeholder'] && 0 === count($choiceList->getChoicesForValues(array('')))) {
+            if (null !== $options['placeholder'] && 0 === \count($choiceList->getChoicesForValues(array('')))) {
                 $placeholderView = new ChoiceView(null, '', $options['placeholder']);
 
                 // "placeholder" is a reserved name
@@ -96,7 +96,7 @@ class ChoiceType extends AbstractType
 
                 // Convert the submitted data to a string, if scalar, before
                 // casting it to an array
-                if (!is_array($data)) {
+                if (!\is_array($data)) {
                     $data = (array) (string) $data;
                 }
 
@@ -127,7 +127,7 @@ class ChoiceType extends AbstractType
                 unset($unknownValues['']);
 
                 // Throw exception if unknown values were submitted
-                if (count($unknownValues) > 0) {
+                if (\count($unknownValues) > 0) {
                     throw new TransformationFailedException(sprintf(
                         'The choices "%s" do not exist in the choice list.',
                         implode('", "', array_keys($unknownValues))
@@ -157,12 +157,12 @@ class ChoiceType extends AbstractType
         $builder->addEventListener(FormEvents::PRE_SUBMIT, function (FormEvent $event) {
             $data = $event->getData();
 
-            if (!is_array($data)) {
+            if (!\is_array($data)) {
                 return;
             }
 
             foreach ($data as $v) {
-                if (null !== $v && !is_string($v) && !is_int($v)) {
+                if (null !== $v && !\is_string($v) && !\is_int($v)) {
                     throw new TransformationFailedException('All choices submitted must be NULL, strings or ints.');
                 }
             }
@@ -203,7 +203,7 @@ class ChoiceType extends AbstractType
         // avoid making the type check inside the closure.
         if ($options['multiple']) {
             $view->vars['is_selected'] = function ($choice, array $values) {
-                return in_array($choice, $values, true);
+                return \in_array($choice, $values, true);
             };
         } else {
             $view->vars['is_selected'] = function ($choice, $value) {
@@ -351,7 +351,7 @@ class ChoiceType extends AbstractType
     {
         foreach ($choiceViews as $name => $choiceView) {
             // Flatten groups
-            if (is_array($choiceView)) {
+            if (\is_array($choiceView)) {
                 $this->addSubForms($builder, $choiceView, $options);
                 continue;
             }
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/DateIntervalType.php b/src/Symfony/Component/Form/Extension/Core/Type/DateIntervalType.php
index 777c0ec121..7332b45b91 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/DateIntervalType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/DateIntervalType.php
@@ -186,7 +186,7 @@ class DateIntervalType extends AbstractType
         };
 
         $placeholderNormalizer = function (Options $options, $placeholder) use ($placeholderDefault, $timeParts) {
-            if (is_array($placeholder)) {
+            if (\is_array($placeholder)) {
                 $default = $placeholderDefault($options);
 
                 return array_merge(array_fill_keys($timeParts, $default), $placeholder);
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/DateTimeType.php b/src/Symfony/Component/Form/Extension/Core/Type/DateTimeType.php
index 26412456c5..385b018dd4 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/DateTimeType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/DateTimeType.php
@@ -78,12 +78,12 @@ class DateTimeType extends AbstractType
             $timeParts[] = 'second';
         }
 
-        $dateFormat = is_int($options['date_format']) ? $options['date_format'] : self::DEFAULT_DATE_FORMAT;
+        $dateFormat = \is_int($options['date_format']) ? $options['date_format'] : self::DEFAULT_DATE_FORMAT;
         $timeFormat = self::DEFAULT_TIME_FORMAT;
         $calendar = \IntlDateFormatter::GREGORIAN;
-        $pattern = is_string($options['format']) ? $options['format'] : null;
+        $pattern = \is_string($options['format']) ? $options['format'] : null;
 
-        if (!in_array($dateFormat, self::$acceptedFormats, true)) {
+        if (!\in_array($dateFormat, self::$acceptedFormats, true)) {
             throw new InvalidOptionsException('The "date_format" option must be one of the IntlDateFormatter constants (FULL, LONG, MEDIUM, SHORT) or a string representing a custom format.');
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/DateType.php b/src/Symfony/Component/Form/Extension/Core/Type/DateType.php
index 91aa8e3839..346f3a9e66 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/DateType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/DateType.php
@@ -47,12 +47,12 @@ class DateType extends AbstractType
      */
     public function buildForm(FormBuilderInterface $builder, array $options)
     {
-        $dateFormat = is_int($options['format']) ? $options['format'] : self::DEFAULT_FORMAT;
+        $dateFormat = \is_int($options['format']) ? $options['format'] : self::DEFAULT_FORMAT;
         $timeFormat = \IntlDateFormatter::NONE;
         $calendar = \IntlDateFormatter::GREGORIAN;
-        $pattern = is_string($options['format']) ? $options['format'] : null;
+        $pattern = \is_string($options['format']) ? $options['format'] : null;
 
-        if (!in_array($dateFormat, self::$acceptedFormats, true)) {
+        if (!\in_array($dateFormat, self::$acceptedFormats, true)) {
             throw new InvalidOptionsException('The "format" option must be one of the IntlDateFormatter constants (FULL, LONG, MEDIUM, SHORT) or a string representing a custom format.');
         }
 
@@ -160,7 +160,7 @@ class DateType extends AbstractType
             $pattern = $form->getConfig()->getAttribute('formatter')->getPattern();
 
             // remove special characters unless the format was explicitly specified
-            if (!is_string($options['format'])) {
+            if (!\is_string($options['format'])) {
                 // remove quoted strings first
                 $pattern = preg_replace('/\'[^\']+\'/', '', $pattern);
 
@@ -195,7 +195,7 @@ class DateType extends AbstractType
         };
 
         $placeholderNormalizer = function (Options $options, $placeholder) use ($placeholderDefault) {
-            if (is_array($placeholder)) {
+            if (\is_array($placeholder)) {
                 $default = $placeholderDefault($options);
 
                 return array_merge(
@@ -212,7 +212,7 @@ class DateType extends AbstractType
         };
 
         $choiceTranslationDomainNormalizer = function (Options $options, $choiceTranslationDomain) {
-            if (is_array($choiceTranslationDomain)) {
+            if (\is_array($choiceTranslationDomain)) {
                 $default = false;
 
                 return array_replace(
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/FileType.php b/src/Symfony/Component/Form/Extension/Core/Type/FileType.php
index 36836378ae..1b699d51e8 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/FileType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/FileType.php
@@ -36,7 +36,7 @@ class FileType extends AbstractType
                 $data = array();
                 $files = $event->getData();
 
-                if (!is_array($files)) {
+                if (!\is_array($files)) {
                     $files = array();
                 }
 
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/FormType.php b/src/Symfony/Component/Form/Extension/Core/Type/FormType.php
index 3f671d8216..76d947f8cc 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/FormType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/FormType.php
@@ -123,7 +123,7 @@ class FormType extends BaseType
 
         // Derive "data_class" option from passed "data" object
         $dataClass = function (Options $options) {
-            return isset($options['data']) && is_object($options['data']) ? get_class($options['data']) : null;
+            return isset($options['data']) && \is_object($options['data']) ? \get_class($options['data']) : null;
         };
 
         // Derive "empty_data" closure from "data_class" option
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php b/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php
index df8973d932..cddf2c488a 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php
@@ -192,7 +192,7 @@ class TimeType extends AbstractType
         };
 
         $placeholderNormalizer = function (Options $options, $placeholder) use ($placeholderDefault) {
-            if (is_array($placeholder)) {
+            if (\is_array($placeholder)) {
                 $default = $placeholderDefault($options);
 
                 return array_merge(
@@ -209,7 +209,7 @@ class TimeType extends AbstractType
         };
 
         $choiceTranslationDomainNormalizer = function (Options $options, $choiceTranslationDomain) {
-            if (is_array($choiceTranslationDomain)) {
+            if (\is_array($choiceTranslationDomain)) {
                 $default = false;
 
                 return array_replace(
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/TimezoneType.php b/src/Symfony/Component/Form/Extension/Core/Type/TimezoneType.php
index 3adf18e84f..fb548fd932 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/TimezoneType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/TimezoneType.php
@@ -79,10 +79,10 @@ class TimezoneType extends AbstractType
         foreach (\DateTimeZone::listIdentifiers($regions) as $timezone) {
             $parts = explode('/', $timezone);
 
-            if (count($parts) > 2) {
+            if (\count($parts) > 2) {
                 $region = $parts[0];
                 $name = $parts[1].' - '.$parts[2];
-            } elseif (count($parts) > 1) {
+            } elseif (\count($parts) > 1) {
                 $region = $parts[0];
                 $name = $parts[1];
             } else {
@@ -93,6 +93,6 @@ class TimezoneType extends AbstractType
             $timezones[$region][str_replace('_', ' ', $name)] = $timezone;
         }
 
-        return 1 === count($timezones) ? reset($timezones) : $timezones;
+        return 1 === \count($timezones) ? reset($timezones) : $timezones;
     }
 }
diff --git a/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php b/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php
index 9774304a15..070a5c2f84 100644
--- a/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php
+++ b/src/Symfony/Component/Form/Extension/Csrf/EventListener/CsrfValidationListener.php
@@ -69,7 +69,7 @@ class CsrfValidationListener implements EventSubscriberInterface
                 $form->addError(new FormError($errorMessage));
             }
 
-            if (is_array($data)) {
+            if (\is_array($data)) {
                 unset($data[$this->fieldName]);
                 $event->setData($data);
             }
diff --git a/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php b/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php
index 5a24d6574a..01baa098a3 100644
--- a/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php
+++ b/src/Symfony/Component/Form/Extension/Csrf/Type/FormTypeCsrfExtension.php
@@ -59,7 +59,7 @@ class FormTypeCsrfExtension extends AbstractTypeExtension
             ->addEventSubscriber(new CsrfValidationListener(
                 $options['csrf_field_name'],
                 $options['csrf_token_manager'],
-                $options['csrf_token_id'] ?: ($builder->getName() ?: get_class($builder->getType()->getInnerType())),
+                $options['csrf_token_id'] ?: ($builder->getName() ?: \get_class($builder->getType()->getInnerType())),
                 $options['csrf_message'],
                 $this->translator,
                 $this->translationDomain,
@@ -79,7 +79,7 @@ class FormTypeCsrfExtension extends AbstractTypeExtension
     {
         if ($options['csrf_protection'] && !$view->parent && $options['compound']) {
             $factory = $form->getConfig()->getFormFactory();
-            $tokenId = $options['csrf_token_id'] ?: ($form->getName() ?: get_class($form->getConfig()->getType()->getInnerType()));
+            $tokenId = $options['csrf_token_id'] ?: ($form->getName() ?: \get_class($form->getConfig()->getType()->getInnerType()));
             $data = (string) $options['csrf_token_manager']->getToken($tokenId);
 
             $csrfForm = $factory->createNamed($options['csrf_field_name'], 'Symfony\Component\Form\Extension\Core\Type\HiddenType', $data, array(
diff --git a/src/Symfony/Component/Form/Extension/DataCollector/FormDataCollector.php b/src/Symfony/Component/Form/Extension/DataCollector/FormDataCollector.php
index a3b7765e12..7ac4f8b693 100644
--- a/src/Symfony/Component/Form/Extension/DataCollector/FormDataCollector.php
+++ b/src/Symfony/Component/Form/Extension/DataCollector/FormDataCollector.php
@@ -162,7 +162,7 @@ class FormDataCollector extends DataCollector implements FormDataCollectorInterf
 
         // Count errors
         if (isset($this->dataByForm[$hash]['errors'])) {
-            $this->data['nb_errors'] += count($this->dataByForm[$hash]['errors']);
+            $this->data['nb_errors'] += \count($this->dataByForm[$hash]['errors']);
         }
 
         foreach ($form as $child) {
@@ -259,7 +259,7 @@ class FormDataCollector extends DataCollector implements FormDataCollectorInterf
             FormInterface::class => function (FormInterface $f, array $a) {
                 return array(
                     Caster::PREFIX_VIRTUAL.'name' => $f->getName(),
-                    Caster::PREFIX_VIRTUAL.'type_class' => new ClassStub(get_class($f->getConfig()->getType()->getInnerType())),
+                    Caster::PREFIX_VIRTUAL.'type_class' => new ClassStub(\get_class($f->getConfig()->getType()->getInnerType())),
                 );
             },
             FormView::class => array(StubCaster::class, 'cutInternals'),
diff --git a/src/Symfony/Component/Form/Extension/DataCollector/FormDataExtractor.php b/src/Symfony/Component/Form/Extension/DataCollector/FormDataExtractor.php
index 9e7a9b579e..cdb1baec8f 100644
--- a/src/Symfony/Component/Form/Extension/DataCollector/FormDataExtractor.php
+++ b/src/Symfony/Component/Form/Extension/DataCollector/FormDataExtractor.php
@@ -30,7 +30,7 @@ class FormDataExtractor implements FormDataExtractorInterface
         $data = array(
             'id' => $this->buildId($form),
             'name' => $form->getName(),
-            'type_class' => get_class($form->getConfig()->getType()->getInnerType()),
+            'type_class' => \get_class($form->getConfig()->getType()->getInnerType()),
             'synchronized' => $form->isSynchronized(),
             'passed_options' => array(),
             'resolved_options' => array(),
@@ -96,7 +96,7 @@ class FormDataExtractor implements FormDataExtractorInterface
         foreach ($form->getErrors() as $error) {
             $errorData = array(
                 'message' => $error->getMessage(),
-                'origin' => is_object($error->getOrigin())
+                'origin' => \is_object($error->getOrigin())
                     ? spl_object_hash($error->getOrigin())
                     : null,
                 'trace' => array(),
diff --git a/src/Symfony/Component/Form/Extension/HttpFoundation/HttpFoundationRequestHandler.php b/src/Symfony/Component/Form/Extension/HttpFoundation/HttpFoundationRequestHandler.php
index 571db0eb41..0a1297d3ab 100644
--- a/src/Symfony/Component/Form/Extension/HttpFoundation/HttpFoundationRequestHandler.php
+++ b/src/Symfony/Component/Form/Extension/HttpFoundation/HttpFoundationRequestHandler.php
@@ -73,7 +73,7 @@ class HttpFoundationRequestHandler implements RequestHandlerInterface
                 $form->submit(null, false);
 
                 $form->addError(new FormError(
-                    call_user_func($form->getConfig()->getOption('upload_max_size_message')),
+                    \call_user_func($form->getConfig()->getOption('upload_max_size_message')),
                     null,
                     array('{{ max }}' => $this->serverParams->getNormalizedIniPostMaxSize())
                 ));
@@ -93,7 +93,7 @@ class HttpFoundationRequestHandler implements RequestHandlerInterface
                 return;
             }
 
-            if (is_array($params) && is_array($files)) {
+            if (\is_array($params) && \is_array($files)) {
                 $data = array_replace_recursive($params, $files);
             } else {
                 $data = $params ?: $files;
@@ -101,7 +101,7 @@ class HttpFoundationRequestHandler implements RequestHandlerInterface
         }
 
         // Don't auto-submit the form unless at least one field is present.
-        if ('' === $name && count(array_intersect_key($data, $form->all())) <= 0) {
+        if ('' === $name && \count(array_intersect_key($data, $form->all())) <= 0) {
             return;
         }
 
diff --git a/src/Symfony/Component/Form/Extension/Templating/TemplatingRendererEngine.php b/src/Symfony/Component/Form/Extension/Templating/TemplatingRendererEngine.php
index 7d389828ea..b26c9ef1dd 100644
--- a/src/Symfony/Component/Form/Extension/Templating/TemplatingRendererEngine.php
+++ b/src/Symfony/Component/Form/Extension/Templating/TemplatingRendererEngine.php
@@ -60,7 +60,7 @@ class TemplatingRendererEngine extends AbstractRendererEngine
 
         // Check each theme whether it contains the searched block
         if (isset($this->themes[$cacheKey])) {
-            for ($i = count($this->themes[$cacheKey]) - 1; $i >= 0; --$i) {
+            for ($i = \count($this->themes[$cacheKey]) - 1; $i >= 0; --$i) {
                 if ($this->loadResourceFromTheme($cacheKey, $blockName, $this->themes[$cacheKey][$i])) {
                     return true;
                 }
@@ -70,7 +70,7 @@ class TemplatingRendererEngine extends AbstractRendererEngine
         // Check the default themes once we reach the root form without success
         if (!$view->parent) {
             if (!isset($this->useDefaultThemes[$cacheKey]) || $this->useDefaultThemes[$cacheKey]) {
-                for ($i = count($this->defaultThemes) - 1; $i >= 0; --$i) {
+                for ($i = \count($this->defaultThemes) - 1; $i >= 0; --$i) {
                     if ($this->loadResourceFromTheme($cacheKey, $blockName, $this->defaultThemes[$i])) {
                         return true;
                     }
diff --git a/src/Symfony/Component/Form/Extension/Validator/Constraints/FormValidator.php b/src/Symfony/Component/Form/Extension/Validator/Constraints/FormValidator.php
index 273db0dbd2..3168a8ee1b 100644
--- a/src/Symfony/Component/Form/Extension/Validator/Constraints/FormValidator.php
+++ b/src/Symfony/Component/Form/Extension/Validator/Constraints/FormValidator.php
@@ -47,8 +47,8 @@ class FormValidator extends ConstraintValidator
             $data = $form->getData();
 
             // Validate the data against its own constraints
-            if ($form->isRoot() && (is_object($data) || is_array($data))) {
-                if (is_array($groups) && count($groups) > 0 || $groups instanceof GroupSequence && count($groups->groups) > 0) {
+            if ($form->isRoot() && (\is_object($data) || \is_array($data))) {
+                if (\is_array($groups) && \count($groups) > 0 || $groups instanceof GroupSequence && \count($groups->groups) > 0) {
                     $validator->atPath('data')->validate($form->getData(), null, $groups);
                 }
             }
@@ -62,9 +62,9 @@ class FormValidator extends ConstraintValidator
                 // Otherwise validate a constraint only once for the first
                 // matching group
                 foreach ($groups as $group) {
-                    if (in_array($group, $constraint->groups)) {
+                    if (\in_array($group, $constraint->groups)) {
                         $validator->atPath('data')->validate($form->getData(), $constraint, $group);
-                        if (count($this->context->getViolations()) > 0) {
+                        if (\count($this->context->getViolations()) > 0) {
                             break;
                         }
                     }
@@ -81,7 +81,7 @@ class FormValidator extends ConstraintValidator
                     // Otherwise validate a constraint only once for the first
                     // matching group
                     foreach ($groups as $group) {
-                        if (in_array($group, $constraint->groups)) {
+                        if (\in_array($group, $constraint->groups)) {
                             $validator->atPath('data')->validate($form->getData(), $constraint, $group);
 
                             // Prevent duplicate validation
@@ -111,7 +111,7 @@ class FormValidator extends ConstraintValidator
             if ($childrenSynchronized) {
                 $clientDataAsString = is_scalar($form->getViewData())
                     ? (string) $form->getViewData()
-                    : gettype($form->getViewData());
+                    : \gettype($form->getViewData());
 
                 $this->context->setConstraint($constraint);
                 $this->context->buildViolation($config->getOption('invalid_message'))
@@ -124,7 +124,7 @@ class FormValidator extends ConstraintValidator
         }
 
         // Mark the form with an error if it contains extra fields
-        if (!$config->getOption('allow_extra_fields') && count($form->getExtraData()) > 0) {
+        if (!$config->getOption('allow_extra_fields') && \count($form->getExtraData()) > 0) {
             $this->context->setConstraint($constraint);
             $this->context->buildViolation($config->getOption('extra_fields_message'))
                 ->setParameter('{{ extra_fields }}', implode('", "', array_keys($form->getExtraData())))
@@ -179,8 +179,8 @@ class FormValidator extends ConstraintValidator
      */
     private static function resolveValidationGroups($groups, FormInterface $form)
     {
-        if (!is_string($groups) && is_callable($groups)) {
-            $groups = call_user_func($groups, $form);
+        if (!\is_string($groups) && \is_callable($groups)) {
+            $groups = \call_user_func($groups, $form);
         }
 
         if ($groups instanceof GroupSequence) {
diff --git a/src/Symfony/Component/Form/Extension/Validator/Type/BaseValidatorExtension.php b/src/Symfony/Component/Form/Extension/Validator/Type/BaseValidatorExtension.php
index 4f52003c0d..431bf5ecfb 100644
--- a/src/Symfony/Component/Form/Extension/Validator/Type/BaseValidatorExtension.php
+++ b/src/Symfony/Component/Form/Extension/Validator/Type/BaseValidatorExtension.php
@@ -39,7 +39,7 @@ abstract class BaseValidatorExtension extends AbstractTypeExtension
                 return;
             }
 
-            if (is_callable($groups)) {
+            if (\is_callable($groups)) {
                 return $groups;
             }
 
diff --git a/src/Symfony/Component/Form/Extension/Validator/Type/FormTypeValidatorExtension.php b/src/Symfony/Component/Form/Extension/Validator/Type/FormTypeValidatorExtension.php
index 761f93158d..8f862bff74 100644
--- a/src/Symfony/Component/Form/Extension/Validator/Type/FormTypeValidatorExtension.php
+++ b/src/Symfony/Component/Form/Extension/Validator/Type/FormTypeValidatorExtension.php
@@ -49,7 +49,7 @@ class FormTypeValidatorExtension extends BaseValidatorExtension
 
         // Constraint should always be converted to an array
         $constraintsNormalizer = function (Options $options, $constraints) {
-            return is_object($constraints) ? array($constraints) : (array) $constraints;
+            return \is_object($constraints) ? array($constraints) : (array) $constraints;
         };
 
         $resolver->setDefaults(array(
diff --git a/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php b/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php
index 25bc229fa3..fe97a93ed1 100644
--- a/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php
+++ b/src/Symfony/Component/Form/Extension/Validator/Type/UploadValidatorExtension.php
@@ -40,7 +40,7 @@ class UploadValidatorExtension extends AbstractTypeExtension
         $translationDomain = $this->translationDomain;
         $resolver->setNormalizer('upload_max_size_message', function (Options $options, $message) use ($translator, $translationDomain) {
             return function () use ($translator, $translationDomain, $message) {
-                return $translator->trans(call_user_func($message), array(), $translationDomain);
+                return $translator->trans(\call_user_func($message), array(), $translationDomain);
             };
         });
     }
diff --git a/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php b/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
index 207015b2ce..d784c13e69 100644
--- a/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
+++ b/src/Symfony/Component/Form/Extension/Validator/ValidatorTypeGuesser.php
@@ -77,7 +77,7 @@ class ValidatorTypeGuesser implements FormTypeGuesserInterface
      */
     public function guessTypeForConstraint(Constraint $constraint)
     {
-        switch (get_class($constraint)) {
+        switch (\get_class($constraint)) {
             case 'Symfony\Component\Validator\Constraints\Type':
                 switch ($constraint->type) {
                     case 'array':
@@ -162,7 +162,7 @@ class ValidatorTypeGuesser implements FormTypeGuesserInterface
      */
     public function guessRequiredForConstraint(Constraint $constraint)
     {
-        switch (get_class($constraint)) {
+        switch (\get_class($constraint)) {
             case 'Symfony\Component\Validator\Constraints\NotNull':
             case 'Symfony\Component\Validator\Constraints\NotBlank':
             case 'Symfony\Component\Validator\Constraints\IsTrue':
@@ -177,7 +177,7 @@ class ValidatorTypeGuesser implements FormTypeGuesserInterface
      */
     public function guessMaxLengthForConstraint(Constraint $constraint)
     {
-        switch (get_class($constraint)) {
+        switch (\get_class($constraint)) {
             case 'Symfony\Component\Validator\Constraints\Length':
                 if (is_numeric($constraint->max)) {
                     return new ValueGuess($constraint->max, Guess::HIGH_CONFIDENCE);
@@ -185,14 +185,14 @@ class ValidatorTypeGuesser implements FormTypeGuesserInterface
                 break;
 
             case 'Symfony\Component\Validator\Constraints\Type':
-                if (in_array($constraint->type, array('double', 'float', 'numeric', 'real'))) {
+                if (\in_array($constraint->type, array('double', 'float', 'numeric', 'real'))) {
                     return new ValueGuess(null, Guess::MEDIUM_CONFIDENCE);
                 }
                 break;
 
             case 'Symfony\Component\Validator\Constraints\Range':
                 if (is_numeric($constraint->max)) {
-                    return new ValueGuess(strlen((string) $constraint->max), Guess::LOW_CONFIDENCE);
+                    return new ValueGuess(\strlen((string) $constraint->max), Guess::LOW_CONFIDENCE);
                 }
                 break;
         }
@@ -205,7 +205,7 @@ class ValidatorTypeGuesser implements FormTypeGuesserInterface
      */
     public function guessPatternForConstraint(Constraint $constraint)
     {
-        switch (get_class($constraint)) {
+        switch (\get_class($constraint)) {
             case 'Symfony\Component\Validator\Constraints\Length':
                 if (is_numeric($constraint->min)) {
                     return new ValueGuess(sprintf('.{%s,}', (string) $constraint->min), Guess::LOW_CONFIDENCE);
@@ -222,12 +222,12 @@ class ValidatorTypeGuesser implements FormTypeGuesserInterface
 
             case 'Symfony\Component\Validator\Constraints\Range':
                 if (is_numeric($constraint->min)) {
-                    return new ValueGuess(sprintf('.{%s,}', strlen((string) $constraint->min)), Guess::LOW_CONFIDENCE);
+                    return new ValueGuess(sprintf('.{%s,}', \strlen((string) $constraint->min)), Guess::LOW_CONFIDENCE);
                 }
                 break;
 
             case 'Symfony\Component\Validator\Constraints\Type':
-                if (in_array($constraint->type, array('double', 'float', 'numeric', 'real'))) {
+                if (\in_array($constraint->type, array('double', 'float', 'numeric', 'real'))) {
                     return new ValueGuess(null, Guess::MEDIUM_CONFIDENCE);
                 }
                 break;
diff --git a/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/MappingRule.php b/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/MappingRule.php
index 4f31227408..32efaded2b 100644
--- a/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/MappingRule.php
+++ b/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/MappingRule.php
@@ -64,7 +64,7 @@ class MappingRule
      */
     public function isPrefix($propertyPath)
     {
-        $length = strlen($propertyPath);
+        $length = \strlen($propertyPath);
         $prefix = substr($this->propertyPath, 0, $length);
         $next = isset($this->propertyPath[$length]) ? $this->propertyPath[$length] : null;
 
diff --git a/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationMapper.php b/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationMapper.php
index 8a3602e701..1aca2c8077 100644
--- a/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationMapper.php
+++ b/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationMapper.php
@@ -48,7 +48,7 @@ class ViolationMapper implements ViolationMapperInterface
         $match = false;
 
         // Don't create a ViolationPath instance for empty property paths
-        if (strlen($violation->getPropertyPath()) > 0) {
+        if (\strlen($violation->getPropertyPath()) > 0) {
             $violationPath = new ViolationPath($violation->getPropertyPath());
             $relativePath = $this->reconstructPath($violationPath, $form);
         }
diff --git a/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationPath.php b/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationPath.php
index 72c4cacfec..acfa5eab9c 100644
--- a/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationPath.php
+++ b/src/Symfony/Component/Form/Extension/Validator/ViolationMapper/ViolationPath.php
@@ -56,7 +56,7 @@ class ViolationPath implements \IteratorAggregate, PropertyPathInterface
         $elements = $path->getElements();
         $data = false;
 
-        for ($i = 0, $l = count($elements); $i < $l; ++$i) {
+        for ($i = 0, $l = \count($elements); $i < $l; ++$i) {
             if (!$data) {
                 // The element "data" has not yet been passed
                 if ('children' === $elements[$i] && $path->isProperty($i)) {
@@ -107,7 +107,7 @@ class ViolationPath implements \IteratorAggregate, PropertyPathInterface
             }
         }
 
-        $this->length = count($this->elements);
+        $this->length = \count($this->elements);
 
         $this->buildString();
     }
diff --git a/src/Symfony/Component/Form/Form.php b/src/Symfony/Component/Form/Form.php
index 625cfe8352..c01de033ab 100644
--- a/src/Symfony/Component/Form/Form.php
+++ b/src/Symfony/Component/Form/Form.php
@@ -322,7 +322,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
             return $this;
         }
 
-        if (is_object($modelData) && !$this->config->getByReference()) {
+        if (\is_object($modelData) && !$this->config->getByReference()) {
             $modelData = clone $modelData;
         }
 
@@ -354,9 +354,9 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
             $dataClass = $this->config->getDataClass();
 
             if (null !== $dataClass && !$viewData instanceof $dataClass) {
-                $actualType = is_object($viewData)
-                    ? 'an instance of class '.get_class($viewData)
-                    : 'a(n) '.gettype($viewData);
+                $actualType = \is_object($viewData)
+                    ? 'an instance of class '.\get_class($viewData)
+                    : 'a(n) '.\gettype($viewData);
 
                 throw new LogicException(
                     'The form\'s view data is expected to be an instance of class '.
@@ -376,7 +376,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
 
         // It is not necessary to invoke this method if the form doesn't have children,
         // even if the form is compound.
-        if (count($this->children) > 0) {
+        if (\count($this->children) > 0) {
             // Update child forms from the data
             $iterator = new InheritDataAwareIterator($this->children);
             $iterator = new \RecursiveIteratorIterator($iterator);
@@ -561,7 +561,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
                     $submittedData = array();
                 }
 
-                if (!is_array($submittedData)) {
+                if (!\is_array($submittedData)) {
                     throw new TransformationFailedException('Compound forms expect an array or NULL on submission.');
                 }
 
@@ -618,7 +618,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
                 // Merge form data from children into existing view data
                 // It is not necessary to invoke this method if the form has no children,
                 // even if it is compound.
-                if (count($this->children) > 0) {
+                if (\count($this->children) > 0) {
                     // Use InheritDataAwareIterator to process children of
                     // descendants that inherit this form's data.
                     // These descendants will not be submitted normally (see the check
@@ -723,7 +723,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
 
         return FormUtil::isEmpty($this->modelData) ||
             // arrays, countables
-            ((is_array($this->modelData) || $this->modelData instanceof \Countable) && 0 === count($this->modelData)) ||
+            ((\is_array($this->modelData) || $this->modelData instanceof \Countable) && 0 === \count($this->modelData)) ||
             // traversables that are not countable
             ($this->modelData instanceof \Traversable && 0 === iterator_count($this->modelData));
     }
@@ -741,7 +741,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
             return true;
         }
 
-        return 0 === count($this->getErrors(true));
+        return 0 === \count($this->getErrors(true));
     }
 
     /**
@@ -778,7 +778,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
 
                 $iterator = $child->getErrors(true, $flatten);
 
-                if (0 === count($iterator)) {
+                if (0 === \count($iterator)) {
                     continue;
                 }
 
@@ -861,11 +861,11 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
         }
 
         if (!$child instanceof FormInterface) {
-            if (!is_string($child) && !is_int($child)) {
+            if (!\is_string($child) && !\is_int($child)) {
                 throw new UnexpectedTypeException($child, 'string, integer or Symfony\Component\Form\FormInterface');
             }
 
-            if (null !== $type && !is_string($type) && !$type instanceof FormTypeInterface) {
+            if (null !== $type && !\is_string($type) && !$type instanceof FormTypeInterface) {
                 throw new UnexpectedTypeException($type, 'string or Symfony\Component\Form\FormTypeInterface');
             }
 
@@ -1013,7 +1013,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
      */
     public function count()
     {
-        return count($this->children);
+        return \count($this->children);
     }
 
     /**
@@ -1084,7 +1084,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
         try {
             $transformers = $this->config->getModelTransformers();
 
-            for ($i = count($transformers) - 1; $i >= 0; --$i) {
+            for ($i = \count($transformers) - 1; $i >= 0; --$i) {
                 $value = $transformers[$i]->reverseTransform($value);
             }
         } catch (TransformationFailedException $exception) {
@@ -1151,7 +1151,7 @@ class Form implements \IteratorAggregate, FormInterface, ClearableErrorsInterfac
         }
 
         try {
-            for ($i = count($transformers) - 1; $i >= 0; --$i) {
+            for ($i = \count($transformers) - 1; $i >= 0; --$i) {
                 $value = $transformers[$i]->reverseTransform($value);
             }
         } catch (TransformationFailedException $exception) {
diff --git a/src/Symfony/Component/Form/FormBuilder.php b/src/Symfony/Component/Form/FormBuilder.php
index ce0bbaa9c2..6bc9a938f5 100644
--- a/src/Symfony/Component/Form/FormBuilder.php
+++ b/src/Symfony/Component/Form/FormBuilder.php
@@ -62,11 +62,11 @@ class FormBuilder extends FormConfigBuilder implements \IteratorAggregate, FormB
             return $this;
         }
 
-        if (!is_string($child) && !is_int($child)) {
+        if (!\is_string($child) && !\is_int($child)) {
             throw new UnexpectedTypeException($child, 'string, integer or Symfony\Component\Form\FormBuilderInterface');
         }
 
-        if (null !== $type && !is_string($type) && !$type instanceof FormTypeInterface) {
+        if (null !== $type && !\is_string($type) && !$type instanceof FormTypeInterface) {
             throw new UnexpectedTypeException($type, 'string or Symfony\Component\Form\FormTypeInterface');
         }
 
@@ -177,7 +177,7 @@ class FormBuilder extends FormConfigBuilder implements \IteratorAggregate, FormB
             throw new BadMethodCallException('FormBuilder methods cannot be accessed anymore once the builder is turned into a FormConfigInterface instance.');
         }
 
-        return count($this->children);
+        return \count($this->children);
     }
 
     /**
diff --git a/src/Symfony/Component/Form/FormConfigBuilder.php b/src/Symfony/Component/Form/FormConfigBuilder.php
index e3660e19ad..15c0080c83 100644
--- a/src/Symfony/Component/Form/FormConfigBuilder.php
+++ b/src/Symfony/Component/Form/FormConfigBuilder.php
@@ -790,7 +790,7 @@ class FormConfigBuilder implements FormConfigBuilderInterface
 
         $upperCaseMethod = strtoupper($method);
 
-        if (!in_array($upperCaseMethod, self::$allowedMethods)) {
+        if (!\in_array($upperCaseMethod, self::$allowedMethods)) {
             throw new InvalidArgumentException(sprintf(
                 'The form method is "%s", but should be one of "%s".',
                 $method,
@@ -857,7 +857,7 @@ class FormConfigBuilder implements FormConfigBuilderInterface
      */
     public static function validateName($name)
     {
-        if (null !== $name && !is_string($name) && !is_int($name)) {
+        if (null !== $name && !\is_string($name) && !\is_int($name)) {
             throw new UnexpectedTypeException($name, 'string, integer or null');
         }
 
diff --git a/src/Symfony/Component/Form/FormErrorIterator.php b/src/Symfony/Component/Form/FormErrorIterator.php
index 857fde678c..a02142605c 100644
--- a/src/Symfony/Component/Form/FormErrorIterator.php
+++ b/src/Symfony/Component/Form/FormErrorIterator.php
@@ -55,7 +55,7 @@ class FormErrorIterator implements \RecursiveIterator, \SeekableIterator, \Array
                     'The errors must be instances of '.
                     '"\Symfony\Component\Form\FormError" or "%s". Got: "%s".',
                     __CLASS__,
-                    is_object($error) ? get_class($error) : gettype($error)
+                    \is_object($error) ? \get_class($error) : \gettype($error)
                 ));
             }
         }
@@ -234,7 +234,7 @@ class FormErrorIterator implements \RecursiveIterator, \SeekableIterator, \Array
      */
     public function count()
     {
-        return count($this->errors);
+        return \count($this->errors);
     }
 
     /**
@@ -270,7 +270,7 @@ class FormErrorIterator implements \RecursiveIterator, \SeekableIterator, \Array
         $errors = array();
         foreach ($this as $error) {
             $cause = $error->getCause();
-            if ($cause instanceof ConstraintViolation && in_array($cause->getCode(), $codes, true)) {
+            if ($cause instanceof ConstraintViolation && \in_array($cause->getCode(), $codes, true)) {
                 $errors[] = $error;
             }
         }
diff --git a/src/Symfony/Component/Form/FormFactory.php b/src/Symfony/Component/Form/FormFactory.php
index 886cdee630..3f18ccf325 100644
--- a/src/Symfony/Component/Form/FormFactory.php
+++ b/src/Symfony/Component/Form/FormFactory.php
@@ -51,7 +51,7 @@ class FormFactory implements FormFactoryInterface
      */
     public function createBuilder($type = 'Symfony\Component\Form\Extension\Core\Type\FormType', $data = null, array $options = array())
     {
-        if (!is_string($type)) {
+        if (!\is_string($type)) {
             throw new UnexpectedTypeException($type, 'string');
         }
 
@@ -67,7 +67,7 @@ class FormFactory implements FormFactoryInterface
             $options['data'] = $data;
         }
 
-        if (!is_string($type)) {
+        if (!\is_string($type)) {
             throw new UnexpectedTypeException($type, 'string');
         }
 
diff --git a/src/Symfony/Component/Form/FormFactoryBuilder.php b/src/Symfony/Component/Form/FormFactoryBuilder.php
index 2f72e7a9a9..3afe1f5359 100644
--- a/src/Symfony/Component/Form/FormFactoryBuilder.php
+++ b/src/Symfony/Component/Form/FormFactoryBuilder.php
@@ -144,8 +144,8 @@ class FormFactoryBuilder implements FormFactoryBuilderInterface
     {
         $extensions = $this->extensions;
 
-        if (count($this->types) > 0 || count($this->typeExtensions) > 0 || count($this->typeGuessers) > 0) {
-            if (count($this->typeGuessers) > 1) {
+        if (\count($this->types) > 0 || \count($this->typeExtensions) > 0 || \count($this->typeGuessers) > 0) {
+            if (\count($this->typeGuessers) > 1) {
                 $typeGuesser = new FormTypeGuesserChain($this->typeGuessers);
             } else {
                 $typeGuesser = isset($this->typeGuessers[0]) ? $this->typeGuessers[0] : null;
diff --git a/src/Symfony/Component/Form/FormRegistry.php b/src/Symfony/Component/Form/FormRegistry.php
index cb8facdac0..eb544e3b07 100644
--- a/src/Symfony/Component/Form/FormRegistry.php
+++ b/src/Symfony/Component/Form/FormRegistry.php
@@ -110,7 +110,7 @@ class FormRegistry implements FormRegistryInterface
     {
         $typeExtensions = array();
         $parentType = $type->getParent();
-        $fqcn = get_class($type);
+        $fqcn = \get_class($type);
 
         if (isset($this->checkedTypes[$fqcn])) {
             $types = implode(' > ', array_merge(array_keys($this->checkedTypes), array($fqcn)));
diff --git a/src/Symfony/Component/Form/FormRenderer.php b/src/Symfony/Component/Form/FormRenderer.php
index 87e612d9a5..e05a39939f 100644
--- a/src/Symfony/Component/Form/FormRenderer.php
+++ b/src/Symfony/Component/Form/FormRenderer.php
@@ -177,7 +177,7 @@ class FormRenderer implements FormRendererInterface
             foreach ($view->vars['block_prefixes'] as $blockNamePrefix) {
                 $blockNameHierarchy[] = $blockNamePrefix.'_'.$blockNameSuffix;
             }
-            $hierarchyLevel = count($blockNameHierarchy) - 1;
+            $hierarchyLevel = \count($blockNameHierarchy) - 1;
 
             $hierarchyInit = true;
         } else {
@@ -221,7 +221,7 @@ class FormRenderer implements FormRendererInterface
 
         // Escape if no resource exists for this block
         if (!$resource) {
-            if (count($blockNameHierarchy) !== count(array_unique($blockNameHierarchy))) {
+            if (\count($blockNameHierarchy) !== \count(array_unique($blockNameHierarchy))) {
                 throw new LogicException(sprintf('Unable to render the form because the block names array contains duplicates: "%s".', implode('", "', array_reverse($blockNameHierarchy))));
             }
 
diff --git a/src/Symfony/Component/Form/FormView.php b/src/Symfony/Component/Form/FormView.php
index 9fbca43796..25e9980f31 100644
--- a/src/Symfony/Component/Form/FormView.php
+++ b/src/Symfony/Component/Form/FormView.php
@@ -63,7 +63,7 @@ class FormView implements \ArrayAccess, \IteratorAggregate, \Countable
      */
     public function isRendered()
     {
-        if (true === $this->rendered || 0 === count($this->children)) {
+        if (true === $this->rendered || 0 === \count($this->children)) {
             return $this->rendered;
         }
 
@@ -162,6 +162,6 @@ class FormView implements \ArrayAccess, \IteratorAggregate, \Countable
      */
     public function count()
     {
-        return count($this->children);
+        return \count($this->children);
     }
 }
diff --git a/src/Symfony/Component/Form/NativeRequestHandler.php b/src/Symfony/Component/Form/NativeRequestHandler.php
index 37e1c99a74..ccebdab6d8 100644
--- a/src/Symfony/Component/Form/NativeRequestHandler.php
+++ b/src/Symfony/Component/Form/NativeRequestHandler.php
@@ -78,7 +78,7 @@ class NativeRequestHandler implements RequestHandlerInterface
                 $form->submit(null, false);
 
                 $form->addError(new FormError(
-                    call_user_func($form->getConfig()->getOption('upload_max_size_message')),
+                    \call_user_func($form->getConfig()->getOption('upload_max_size_message')),
                     null,
                     array('{{ max }}' => $this->serverParams->getNormalizedIniPostMaxSize())
                 ));
@@ -103,7 +103,7 @@ class NativeRequestHandler implements RequestHandlerInterface
                 return;
             }
 
-            if (is_array($params) && is_array($files)) {
+            if (\is_array($params) && \is_array($files)) {
                 $data = array_replace_recursive($params, $files);
             } else {
                 $data = $params ?: $files;
@@ -111,7 +111,7 @@ class NativeRequestHandler implements RequestHandlerInterface
         }
 
         // Don't auto-submit the form unless at least one field is present.
-        if ('' === $name && count(array_intersect_key($data, $form->all())) <= 0) {
+        if ('' === $name && \count(array_intersect_key($data, $form->all())) <= 0) {
             return;
         }
 
@@ -126,7 +126,7 @@ class NativeRequestHandler implements RequestHandlerInterface
         // POST data will always be strings or arrays of strings. Thus, we can be sure
         // that the submitted data is a file upload if the "error" value is an integer
         // (this value must have been injected by PHP itself).
-        return is_array($data) && isset($data['error']) && is_int($data['error']);
+        return \is_array($data) && isset($data['error']) && \is_int($data['error']);
     }
 
     /**
@@ -166,14 +166,14 @@ class NativeRequestHandler implements RequestHandlerInterface
      */
     private static function fixPhpFilesArray($data)
     {
-        if (!is_array($data)) {
+        if (!\is_array($data)) {
             return $data;
         }
 
         $keys = array_keys($data);
         sort($keys);
 
-        if (self::$fileKeys !== $keys || !isset($data['name']) || !is_array($data['name'])) {
+        if (self::$fileKeys !== $keys || !isset($data['name']) || !\is_array($data['name'])) {
             return $data;
         }
 
@@ -204,7 +204,7 @@ class NativeRequestHandler implements RequestHandlerInterface
      */
     private static function stripEmptyFiles($data)
     {
-        if (!is_array($data)) {
+        if (!\is_array($data)) {
             return $data;
         }
 
diff --git a/src/Symfony/Component/Form/PreloadedExtension.php b/src/Symfony/Component/Form/PreloadedExtension.php
index be720a3430..b26dbe638d 100644
--- a/src/Symfony/Component/Form/PreloadedExtension.php
+++ b/src/Symfony/Component/Form/PreloadedExtension.php
@@ -37,7 +37,7 @@ class PreloadedExtension implements FormExtensionInterface
         $this->typeGuesser = $typeGuesser;
 
         foreach ($types as $type) {
-            $this->types[get_class($type)] = $type;
+            $this->types[\get_class($type)] = $type;
         }
     }
 
diff --git a/src/Symfony/Component/Form/Test/FormPerformanceTestCase.php b/src/Symfony/Component/Form/Test/FormPerformanceTestCase.php
index dfb4ffaa01..a6d8dc7411 100644
--- a/src/Symfony/Component/Form/Test/FormPerformanceTestCase.php
+++ b/src/Symfony/Component/Form/Test/FormPerformanceTestCase.php
@@ -54,7 +54,7 @@ abstract class FormPerformanceTestCase extends FormIntegrationTestCase
      */
     public function setMaxRunningTime($maxRunningTime)
     {
-        if (is_int($maxRunningTime) && $maxRunningTime >= 0) {
+        if (\is_int($maxRunningTime) && $maxRunningTime >= 0) {
             $this->maxRunningTime = $maxRunningTime;
         } else {
             throw new \InvalidArgumentException();
diff --git a/src/Symfony/Component/Form/Test/TypeTestCase.php b/src/Symfony/Component/Form/Test/TypeTestCase.php
index 346dc61648..7722a7d20b 100644
--- a/src/Symfony/Component/Form/Test/TypeTestCase.php
+++ b/src/Symfony/Component/Form/Test/TypeTestCase.php
@@ -37,7 +37,7 @@ abstract class TypeTestCase extends FormIntegrationTestCase
 
     protected function tearDown()
     {
-        if (in_array(ValidatorExtensionTrait::class, class_uses($this))) {
+        if (\in_array(ValidatorExtensionTrait::class, class_uses($this))) {
             $this->validator = null;
         }
     }
@@ -46,7 +46,7 @@ abstract class TypeTestCase extends FormIntegrationTestCase
     {
         $extensions = array();
 
-        if (in_array(ValidatorExtensionTrait::class, class_uses($this))) {
+        if (\in_array(ValidatorExtensionTrait::class, class_uses($this))) {
             $extensions[] = $this->getValidatorExtension();
         }
 
diff --git a/src/Symfony/Component/Form/Tests/AbstractLayoutTest.php b/src/Symfony/Component/Form/Tests/AbstractLayoutTest.php
index cbe11ae044..1024f0bd43 100644
--- a/src/Symfony/Component/Form/Tests/AbstractLayoutTest.php
+++ b/src/Symfony/Component/Form/Tests/AbstractLayoutTest.php
@@ -24,7 +24,7 @@ abstract class AbstractLayoutTest extends FormIntegrationTestCase
 
     protected function setUp()
     {
-        if (!extension_loaded('intl')) {
+        if (!\extension_loaded('intl')) {
             $this->markTestSkipped('Extension intl is required.');
         }
 
@@ -116,7 +116,7 @@ abstract class AbstractLayoutTest extends FormIntegrationTestCase
 
     protected function renderHelp(FormView $view)
     {
-        $this->markTestSkipped(sprintf('%s::renderHelp() is not implemented.', get_class($this)));
+        $this->markTestSkipped(sprintf('%s::renderHelp() is not implemented.', \get_class($this)));
     }
 
     abstract protected function renderErrors(FormView $view);
diff --git a/src/Symfony/Component/Form/Tests/ChoiceList/Factory/CachingFactoryDecoratorTest.php b/src/Symfony/Component/Form/Tests/ChoiceList/Factory/CachingFactoryDecoratorTest.php
index b038865fd8..dd6c968bd8 100644
--- a/src/Symfony/Component/Form/Tests/ChoiceList/Factory/CachingFactoryDecoratorTest.php
+++ b/src/Symfony/Component/Form/Tests/ChoiceList/Factory/CachingFactoryDecoratorTest.php
@@ -486,7 +486,7 @@ class CachingFactoryDecoratorTest extends TestCase
             array(0, 0),
             array('a', 'a'),
             // https://github.com/symfony/symfony/issues/10409
-            array(chr(181).'meter', chr(181).'meter'), // UTF-8
+            array(\chr(181).'meter', \chr(181).'meter'), // UTF-8
             array($object, $object),
         );
     }
@@ -516,7 +516,7 @@ class CachingFactoryDecoratorTest extends TestCase
             array(0, 0),
             array(0, '0'),
             array('a', 'a'),
-            array(chr(181).'meter', chr(181).'meter'),
+            array(\chr(181).'meter', \chr(181).'meter'),
         );
     }
 
diff --git a/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/MergeCollectionListenerTest.php b/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/MergeCollectionListenerTest.php
index 2dcbc359ea..321d702a1b 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/MergeCollectionListenerTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Core/EventListener/MergeCollectionListenerTest.php
@@ -85,7 +85,7 @@ abstract class MergeCollectionListenerTest extends TestCase
         $listener->onSubmit($event);
 
         // The original object was modified
-        if (is_object($originalData)) {
+        if (\is_object($originalData)) {
             $this->assertSame($originalData, $event->getData());
         }
 
@@ -109,7 +109,7 @@ abstract class MergeCollectionListenerTest extends TestCase
         $listener->onSubmit($event);
 
         // The original object was modified
-        if (is_object($originalData)) {
+        if (\is_object($originalData)) {
             $this->assertSame($originalData, $event->getData());
         }
 
@@ -134,7 +134,7 @@ abstract class MergeCollectionListenerTest extends TestCase
         $listener->onSubmit($event);
 
         // We still have the original object
-        if (is_object($originalData)) {
+        if (\is_object($originalData)) {
             $this->assertSame($originalData, $event->getData());
         }
 
@@ -158,7 +158,7 @@ abstract class MergeCollectionListenerTest extends TestCase
         $listener->onSubmit($event);
 
         // The original object was modified
-        if (is_object($originalData)) {
+        if (\is_object($originalData)) {
             $this->assertSame($originalData, $event->getData());
         }
 
@@ -183,7 +183,7 @@ abstract class MergeCollectionListenerTest extends TestCase
         $listener->onSubmit($event);
 
         // We still have the original object
-        if (is_object($originalData)) {
+        if (\is_object($originalData)) {
             $this->assertSame($originalData, $event->getData());
         }
 
diff --git a/src/Symfony/Component/Form/Tests/Extension/Core/Type/ChoiceTypeTest.php b/src/Symfony/Component/Form/Tests/Extension/Core/Type/ChoiceTypeTest.php
index 1f24323251..e12ab6ff93 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Core/Type/ChoiceTypeTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Core/Type/ChoiceTypeTest.php
@@ -112,7 +112,7 @@ class ChoiceTypeTest extends BaseTypeTest
             'choices' => $this->choices,
         ));
 
-        $this->assertCount(count($this->choices), $form, 'Each choice should become a new field');
+        $this->assertCount(\count($this->choices), $form, 'Each choice should become a new field');
     }
 
     public function testChoiceListWithScalarValues()
@@ -197,7 +197,7 @@ class ChoiceTypeTest extends BaseTypeTest
         ));
 
         $this->assertArrayHasKey('placeholder', $form);
-        $this->assertCount(count($this->choices) + 1, $form, 'Each choice should become a new field');
+        $this->assertCount(\count($this->choices) + 1, $form, 'Each choice should become a new field');
     }
 
     public function testPlaceholderNotPresentIfRequired()
@@ -210,7 +210,7 @@ class ChoiceTypeTest extends BaseTypeTest
         ));
 
         $this->assertArrayNotHasKey('placeholder', $form);
-        $this->assertCount(count($this->choices), $form, 'Each choice should become a new field');
+        $this->assertCount(\count($this->choices), $form, 'Each choice should become a new field');
     }
 
     public function testPlaceholderNotPresentIfMultiple()
@@ -223,7 +223,7 @@ class ChoiceTypeTest extends BaseTypeTest
         ));
 
         $this->assertArrayNotHasKey('placeholder', $form);
-        $this->assertCount(count($this->choices), $form, 'Each choice should become a new field');
+        $this->assertCount(\count($this->choices), $form, 'Each choice should become a new field');
     }
 
     public function testPlaceholderNotPresentIfEmptyChoice()
diff --git a/src/Symfony/Component/Form/Tests/Extension/Core/Type/FormTypeTest.php b/src/Symfony/Component/Form/Tests/Extension/Core/Type/FormTypeTest.php
index ef2edd5a7d..86cc359888 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Core/Type/FormTypeTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Core/Type/FormTypeTest.php
@@ -40,7 +40,7 @@ class FormTest_AuthorWithoutRefSetter
     // to update it
     public function getReferenceCopy()
     {
-        return is_object($this->referenceCopy) ? clone $this->referenceCopy : $this->referenceCopy;
+        return \is_object($this->referenceCopy) ? clone $this->referenceCopy : $this->referenceCopy;
     }
 
     public function setReferenceCopy($reference)
diff --git a/src/Symfony/Component/Form/Tests/Extension/Csrf/Type/FormTypeCsrfExtensionTest.php b/src/Symfony/Component/Form/Tests/Extension/Csrf/Type/FormTypeCsrfExtensionTest.php
index 6432ac6889..3b5e15410a 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Csrf/Type/FormTypeCsrfExtensionTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Csrf/Type/FormTypeCsrfExtensionTest.php
@@ -391,7 +391,7 @@ class FormTypeCsrfExtensionTest extends TypeTestCase
         $expected = new FormError('[trans]Foobar[/trans]');
         $expected->setOrigin($form);
 
-        $this->assertGreaterThan(0, count($errors));
+        $this->assertGreaterThan(0, \count($errors));
         $this->assertEquals($expected, $errors[0]);
     }
 }
diff --git a/src/Symfony/Component/Form/Tests/Extension/DataCollector/FormDataCollectorTest.php b/src/Symfony/Component/Form/Tests/Extension/DataCollector/FormDataCollectorTest.php
index bd3f25bffb..3bfef60253 100644
--- a/src/Symfony/Component/Form/Tests/Extension/DataCollector/FormDataCollectorTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/DataCollector/FormDataCollectorTest.php
@@ -353,7 +353,7 @@ class FormDataCollectorTest extends TestCase
         $form2View = new FormView();
         $child1View = new FormView();
         $child1View->vars['is_selected'] = function ($choice, array $values) {
-            return in_array($choice, $values, true);
+            return \in_array($choice, $values, true);
         };
 
         $form1->add($child1);
diff --git a/src/Symfony/Component/Form/Tests/Extension/Validator/Type/UploadValidatorExtensionTest.php b/src/Symfony/Component/Form/Tests/Extension/Validator/Type/UploadValidatorExtensionTest.php
index 17792b6745..8872263904 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Validator/Type/UploadValidatorExtensionTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Validator/Type/UploadValidatorExtensionTest.php
@@ -40,6 +40,6 @@ class UploadValidatorExtensionTest extends TypeTestCase
         $extension->configureOptions($resolver);
         $options = $resolver->resolve();
 
-        $this->assertEquals('translated max {{ max }}!', call_user_func($options['upload_max_size_message']));
+        $this->assertEquals('translated max {{ max }}!', \call_user_func($options['upload_max_size_message']));
     }
 }
diff --git a/src/Symfony/Component/Form/Tests/Extension/Validator/ViolationMapper/ViolationPathTest.php b/src/Symfony/Component/Form/Tests/Extension/Validator/ViolationMapper/ViolationPathTest.php
index 88d5169cd7..2e1c9f673d 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Validator/ViolationMapper/ViolationPathTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Validator/ViolationMapper/ViolationPathTest.php
@@ -96,8 +96,8 @@ class ViolationPathTest extends TestCase
         $path = new ViolationPath($string);
 
         $this->assertSame($slicedPath, $path->__toString());
-        $this->assertCount(count($entries), $path->getElements());
-        $this->assertSame(count($entries), $path->getLength());
+        $this->assertCount(\count($entries), $path->getElements());
+        $this->assertSame(\count($entries), $path->getLength());
 
         foreach ($entries as $index => $entry) {
             $this->assertEquals($entry[0], $path->getElement($index));
diff --git a/src/Symfony/Component/Form/Tests/Fixtures/CustomArrayObject.php b/src/Symfony/Component/Form/Tests/Fixtures/CustomArrayObject.php
index 950f677fd0..91b2773037 100644
--- a/src/Symfony/Component/Form/Tests/Fixtures/CustomArrayObject.php
+++ b/src/Symfony/Component/Form/Tests/Fixtures/CustomArrayObject.php
@@ -55,7 +55,7 @@ class CustomArrayObject implements \ArrayAccess, \IteratorAggregate, \Countable,
 
     public function count()
     {
-        return count($this->array);
+        return \count($this->array);
     }
 
     public function serialize()
diff --git a/src/Symfony/Component/Form/Tests/Fixtures/TestExtension.php b/src/Symfony/Component/Form/Tests/Fixtures/TestExtension.php
index 042bee5128..ba16baa6f5 100644
--- a/src/Symfony/Component/Form/Tests/Fixtures/TestExtension.php
+++ b/src/Symfony/Component/Form/Tests/Fixtures/TestExtension.php
@@ -31,7 +31,7 @@ class TestExtension implements FormExtensionInterface
 
     public function addType(FormTypeInterface $type)
     {
-        $this->types[get_class($type)] = $type;
+        $this->types[\get_class($type)] = $type;
     }
 
     public function getType($name)
diff --git a/src/Symfony/Component/Form/Tests/FormFactoryBuilderTest.php b/src/Symfony/Component/Form/Tests/FormFactoryBuilderTest.php
index 854f4f347f..3e66ce8c38 100644
--- a/src/Symfony/Component/Form/Tests/FormFactoryBuilderTest.php
+++ b/src/Symfony/Component/Form/Tests/FormFactoryBuilderTest.php
@@ -41,7 +41,7 @@ class FormFactoryBuilderTest extends TestCase
         $extensions = $registry->getExtensions();
 
         $this->assertCount(1, $extensions);
-        $this->assertTrue($extensions[0]->hasType(get_class($this->type)));
+        $this->assertTrue($extensions[0]->hasType(\get_class($this->type)));
         $this->assertNull($extensions[0]->getTypeGuesser());
     }
 
diff --git a/src/Symfony/Component/Form/Tests/FormRegistryTest.php b/src/Symfony/Component/Form/Tests/FormRegistryTest.php
index b304eaed40..0c0a2233d8 100644
--- a/src/Symfony/Component/Form/Tests/FormRegistryTest.php
+++ b/src/Symfony/Component/Form/Tests/FormRegistryTest.php
@@ -86,7 +86,7 @@ class FormRegistryTest extends TestCase
             ->with($type)
             ->willReturn($resolvedType);
 
-        $this->assertSame($resolvedType, $this->registry->getType(get_class($type)));
+        $this->assertSame($resolvedType, $this->registry->getType(\get_class($type)));
     }
 
     public function testLoadUnregisteredType()
@@ -134,7 +134,7 @@ class FormRegistryTest extends TestCase
             ->with($type, array($ext1, $ext2))
             ->willReturn($resolvedType);
 
-        $this->assertSame($resolvedType, $this->registry->getType(get_class($type)));
+        $this->assertSame($resolvedType, $this->registry->getType(\get_class($type)));
     }
 
     public function testGetTypeConnectsParent()
@@ -157,7 +157,7 @@ class FormRegistryTest extends TestCase
             ->with($type, array(), $parentResolvedType)
             ->willReturn($resolvedType);
 
-        $this->assertSame($resolvedType, $this->registry->getType(get_class($type)));
+        $this->assertSame($resolvedType, $this->registry->getType(\get_class($type)));
     }
 
     /**
@@ -210,7 +210,7 @@ class FormRegistryTest extends TestCase
 
         $this->extension2->addType($type);
 
-        $this->assertTrue($this->registry->hasType(get_class($type)));
+        $this->assertTrue($this->registry->hasType(\get_class($type)));
     }
 
     public function testHasTypeIfFQCN()
diff --git a/src/Symfony/Component/Form/Tests/Resources/TranslationFilesTest.php b/src/Symfony/Component/Form/Tests/Resources/TranslationFilesTest.php
index 6d3dae218c..d0bc82e759 100644
--- a/src/Symfony/Component/Form/Tests/Resources/TranslationFilesTest.php
+++ b/src/Symfony/Component/Form/Tests/Resources/TranslationFilesTest.php
@@ -33,15 +33,15 @@ class TranslationFilesTest extends TestCase
     {
         return array_map(
             function ($filePath) { return (array) $filePath; },
-            glob(dirname(dirname(__DIR__)).'/Resources/translations/*.xlf')
+            glob(\dirname(\dirname(__DIR__)).'/Resources/translations/*.xlf')
         );
     }
 
     public function testNorwegianAlias()
     {
         $this->assertFileEquals(
-            dirname(dirname(__DIR__)).'/Resources/translations/validators.nb.xlf',
-            dirname(dirname(__DIR__)).'/Resources/translations/validators.no.xlf',
+            \dirname(\dirname(__DIR__)).'/Resources/translations/validators.nb.xlf',
+            \dirname(\dirname(__DIR__)).'/Resources/translations/validators.no.xlf',
             'The NO locale should be an alias for the NB variant of the Norwegian language.'
         );
     }
diff --git a/src/Symfony/Component/Form/Util/OrderedHashMap.php b/src/Symfony/Component/Form/Util/OrderedHashMap.php
index 24ec0d5299..6a97559850 100644
--- a/src/Symfony/Component/Form/Util/OrderedHashMap.php
+++ b/src/Symfony/Component/Form/Util/OrderedHashMap.php
@@ -169,6 +169,6 @@ class OrderedHashMap implements \ArrayAccess, \IteratorAggregate, \Countable
      */
     public function count()
     {
-        return count($this->elements);
+        return \count($this->elements);
     }
 }
diff --git a/src/Symfony/Component/Form/Util/OrderedHashMapIterator.php b/src/Symfony/Component/Form/Util/OrderedHashMapIterator.php
index d9d874af61..3de636392d 100644
--- a/src/Symfony/Component/Form/Util/OrderedHashMapIterator.php
+++ b/src/Symfony/Component/Form/Util/OrderedHashMapIterator.php
@@ -73,7 +73,7 @@ class OrderedHashMapIterator implements \Iterator
         $this->elements = &$elements;
         $this->orderedKeys = &$orderedKeys;
         $this->managedCursors = &$managedCursors;
-        $this->cursorId = count($managedCursors);
+        $this->cursorId = \count($managedCursors);
 
         $this->managedCursors[$this->cursorId] = &$this->cursor;
     }
diff --git a/src/Symfony/Component/Form/Util/ServerParams.php b/src/Symfony/Component/Form/Util/ServerParams.php
index fc5e9dd27a..3d5b76a7c2 100644
--- a/src/Symfony/Component/Form/Util/ServerParams.php
+++ b/src/Symfony/Component/Form/Util/ServerParams.php
@@ -53,9 +53,9 @@ class ServerParams
 
         $max = ltrim($iniMax, '+');
         if (0 === strpos($max, '0x')) {
-            $max = intval($max, 16);
+            $max = \intval($max, 16);
         } elseif (0 === strpos($max, '0')) {
-            $max = intval($max, 8);
+            $max = \intval($max, 8);
         } else {
             $max = (int) $max;
         }
diff --git a/src/Symfony/Component/HttpFoundation/AcceptHeaderItem.php b/src/Symfony/Component/HttpFoundation/AcceptHeaderItem.php
index f874259857..97f60c8a0d 100644
--- a/src/Symfony/Component/HttpFoundation/AcceptHeaderItem.php
+++ b/src/Symfony/Component/HttpFoundation/AcceptHeaderItem.php
@@ -56,7 +56,7 @@ class AcceptHeaderItem
     public function __toString()
     {
         $string = $this->value.($this->quality < 1 ? ';q='.$this->quality : '');
-        if (count($this->attributes) > 0) {
+        if (\count($this->attributes) > 0) {
             $string .= '; '.HeaderUtils::toString($this->attributes, ';');
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/ApacheRequest.php b/src/Symfony/Component/HttpFoundation/ApacheRequest.php
index 84803ebae2..4e99186dcd 100644
--- a/src/Symfony/Component/HttpFoundation/ApacheRequest.php
+++ b/src/Symfony/Component/HttpFoundation/ApacheRequest.php
@@ -35,7 +35,7 @@ class ApacheRequest extends Request
 
         if (false === strpos($this->server->get('REQUEST_URI'), $baseUrl)) {
             // assume mod_rewrite
-            return rtrim(dirname($baseUrl), '/\\');
+            return rtrim(\dirname($baseUrl), '/\\');
         }
 
         return $baseUrl;
diff --git a/src/Symfony/Component/HttpFoundation/BinaryFileResponse.php b/src/Symfony/Component/HttpFoundation/BinaryFileResponse.php
index b549c24b62..1f3081d34a 100644
--- a/src/Symfony/Component/HttpFoundation/BinaryFileResponse.php
+++ b/src/Symfony/Component/HttpFoundation/BinaryFileResponse.php
@@ -165,7 +165,7 @@ class BinaryFileResponse extends Response
             for ($i = 0, $filenameLength = mb_strlen($filename, $encoding); $i < $filenameLength; ++$i) {
                 $char = mb_substr($filename, $i, 1, $encoding);
 
-                if ('%' === $char || ord($char) < 32 || ord($char) > 126) {
+                if ('%' === $char || \ord($char) < 32 || \ord($char) > 126) {
                     $filenameFallback .= '_';
                 } else {
                     $filenameFallback .= $char;
@@ -221,8 +221,8 @@ class BinaryFileResponse extends Response
                 $parts = HeaderUtils::split($request->headers->get('X-Accel-Mapping', ''), ',=');
                 $mappings = HeaderUtils::combine($parts);
                 foreach ($mappings as $pathPrefix => $location) {
-                    if (substr($path, 0, strlen($pathPrefix)) === $pathPrefix) {
-                        $path = $location.substr($path, strlen($pathPrefix));
+                    if (substr($path, 0, \strlen($pathPrefix)) === $pathPrefix) {
+                        $path = $location.substr($path, \strlen($pathPrefix));
                         break;
                     }
                 }
diff --git a/src/Symfony/Component/HttpFoundation/Cookie.php b/src/Symfony/Component/HttpFoundation/Cookie.php
index ff74aee54b..80a8f69c68 100644
--- a/src/Symfony/Component/HttpFoundation/Cookie.php
+++ b/src/Symfony/Component/HttpFoundation/Cookie.php
@@ -114,7 +114,7 @@ class Cookie
             $sameSite = strtolower($sameSite);
         }
 
-        if (!in_array($sameSite, array(self::SAMESITE_LAX, self::SAMESITE_STRICT, null), true)) {
+        if (!\in_array($sameSite, array(self::SAMESITE_LAX, self::SAMESITE_STRICT, null), true)) {
             throw new \InvalidArgumentException('The "sameSite" parameter value is not valid.');
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/File/Exception/UnexpectedTypeException.php b/src/Symfony/Component/HttpFoundation/File/Exception/UnexpectedTypeException.php
index 82e6691fff..82b982b378 100644
--- a/src/Symfony/Component/HttpFoundation/File/Exception/UnexpectedTypeException.php
+++ b/src/Symfony/Component/HttpFoundation/File/Exception/UnexpectedTypeException.php
@@ -15,6 +15,6 @@ class UnexpectedTypeException extends FileException
 {
     public function __construct($value, string $expectedType)
     {
-        parent::__construct(sprintf('Expected argument of type %s, %s given', $expectedType, is_object($value) ? get_class($value) : gettype($value)));
+        parent::__construct(sprintf('Expected argument of type %s, %s given', $expectedType, \is_object($value) ? \get_class($value) : \gettype($value)));
     }
 }
diff --git a/src/Symfony/Component/HttpFoundation/File/MimeType/FileBinaryMimeTypeGuesser.php b/src/Symfony/Component/HttpFoundation/File/MimeType/FileBinaryMimeTypeGuesser.php
index 83be44af67..c5fbedc9e2 100644
--- a/src/Symfony/Component/HttpFoundation/File/MimeType/FileBinaryMimeTypeGuesser.php
+++ b/src/Symfony/Component/HttpFoundation/File/MimeType/FileBinaryMimeTypeGuesser.php
@@ -49,7 +49,7 @@ class FileBinaryMimeTypeGuesser implements MimeTypeGuesserInterface
             return $supported;
         }
 
-        if ('\\' === DIRECTORY_SEPARATOR || !function_exists('passthru') || !function_exists('escapeshellarg')) {
+        if ('\\' === DIRECTORY_SEPARATOR || !\function_exists('passthru') || !\function_exists('escapeshellarg')) {
             return $supported = false;
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/File/MimeType/FileinfoMimeTypeGuesser.php b/src/Symfony/Component/HttpFoundation/File/MimeType/FileinfoMimeTypeGuesser.php
index d3ba8b31b5..6b2fddff38 100644
--- a/src/Symfony/Component/HttpFoundation/File/MimeType/FileinfoMimeTypeGuesser.php
+++ b/src/Symfony/Component/HttpFoundation/File/MimeType/FileinfoMimeTypeGuesser.php
@@ -40,7 +40,7 @@ class FileinfoMimeTypeGuesser implements MimeTypeGuesserInterface
      */
     public static function isSupported()
     {
-        return function_exists('finfo_open');
+        return \function_exists('finfo_open');
     }
 
     /**
diff --git a/src/Symfony/Component/HttpFoundation/File/UploadedFile.php b/src/Symfony/Component/HttpFoundation/File/UploadedFile.php
index 594decb067..63fa6c7302 100644
--- a/src/Symfony/Component/HttpFoundation/File/UploadedFile.php
+++ b/src/Symfony/Component/HttpFoundation/File/UploadedFile.php
@@ -65,10 +65,10 @@ class UploadedFile extends File
         $this->originalName = $this->getName($originalName);
         $this->mimeType = $mimeType ?: 'application/octet-stream';
 
-        if (4 < func_num_args() ? !is_bool($test) : null !== $error && @filesize($path) === $error) {
+        if (4 < \func_num_args() ? !\is_bool($test) : null !== $error && @filesize($path) === $error) {
             @trigger_error(sprintf('Passing a size as 4th argument to the constructor of "%s" is deprecated since Symfony 4.1.', __CLASS__), E_USER_DEPRECATED);
             $error = $test;
-            $test = 5 < func_num_args() ? func_get_arg(5) : false;
+            $test = 5 < \func_num_args() ? func_get_arg(5) : false;
         }
 
         $this->error = $error ?: UPLOAD_ERR_OK;
@@ -254,9 +254,9 @@ class UploadedFile extends File
 
         $max = ltrim($iniMax, '+');
         if (0 === strpos($max, '0x')) {
-            $max = intval($max, 16);
+            $max = \intval($max, 16);
         } elseif (0 === strpos($max, '0')) {
-            $max = intval($max, 8);
+            $max = \intval($max, 8);
         } else {
             $max = (int) $max;
         }
diff --git a/src/Symfony/Component/HttpFoundation/FileBag.php b/src/Symfony/Component/HttpFoundation/FileBag.php
index f0d97caca2..f37e10f204 100644
--- a/src/Symfony/Component/HttpFoundation/FileBag.php
+++ b/src/Symfony/Component/HttpFoundation/FileBag.php
@@ -45,7 +45,7 @@ class FileBag extends ParameterBag
      */
     public function set($key, $value)
     {
-        if (!is_array($value) && !$value instanceof UploadedFile) {
+        if (!\is_array($value) && !$value instanceof UploadedFile) {
             throw new \InvalidArgumentException('An uploaded file must be an array or an instance of UploadedFile.');
         }
 
@@ -76,7 +76,7 @@ class FileBag extends ParameterBag
         }
 
         $file = $this->fixPhpFilesArray($file);
-        if (is_array($file)) {
+        if (\is_array($file)) {
             $keys = array_keys($file);
             sort($keys);
 
@@ -113,14 +113,14 @@ class FileBag extends ParameterBag
      */
     protected function fixPhpFilesArray($data)
     {
-        if (!is_array($data)) {
+        if (!\is_array($data)) {
             return $data;
         }
 
         $keys = array_keys($data);
         sort($keys);
 
-        if (self::$fileKeys != $keys || !isset($data['name']) || !is_array($data['name'])) {
+        if (self::$fileKeys != $keys || !isset($data['name']) || !\is_array($data['name'])) {
             return $data;
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/HeaderBag.php b/src/Symfony/Component/HttpFoundation/HeaderBag.php
index d11887fb61..221ff61b37 100644
--- a/src/Symfony/Component/HttpFoundation/HeaderBag.php
+++ b/src/Symfony/Component/HttpFoundation/HeaderBag.php
@@ -181,7 +181,7 @@ class HeaderBag implements \IteratorAggregate, \Countable
      */
     public function contains($key, $value)
     {
-        return in_array($value, $this->get($key, null, false));
+        return \in_array($value, $this->get($key, null, false));
     }
 
     /**
@@ -289,7 +289,7 @@ class HeaderBag implements \IteratorAggregate, \Countable
      */
     public function count()
     {
-        return count($this->headers);
+        return \count($this->headers);
     }
 
     protected function getCacheControlHeader()
diff --git a/src/Symfony/Component/HttpFoundation/IpUtils.php b/src/Symfony/Component/HttpFoundation/IpUtils.php
index 86d135b2d3..a1bfa90885 100644
--- a/src/Symfony/Component/HttpFoundation/IpUtils.php
+++ b/src/Symfony/Component/HttpFoundation/IpUtils.php
@@ -37,7 +37,7 @@ class IpUtils
      */
     public static function checkIp($requestIp, $ips)
     {
-        if (!is_array($ips)) {
+        if (!\is_array($ips)) {
             $ips = array($ips);
         }
 
@@ -116,7 +116,7 @@ class IpUtils
             return self::$checkedIps[$cacheKey];
         }
 
-        if (!((extension_loaded('sockets') && defined('AF_INET6')) || @inet_pton('::1'))) {
+        if (!((\extension_loaded('sockets') && \defined('AF_INET6')) || @inet_pton('::1'))) {
             throw new \RuntimeException('Unable to check Ipv6. Check that PHP was not compiled with option "disable-ipv6".');
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/JsonResponse.php b/src/Symfony/Component/HttpFoundation/JsonResponse.php
index 7292640290..f10262e88e 100644
--- a/src/Symfony/Component/HttpFoundation/JsonResponse.php
+++ b/src/Symfony/Component/HttpFoundation/JsonResponse.php
@@ -101,7 +101,7 @@ class JsonResponse extends Response
             );
             $parts = explode('.', $callback);
             foreach ($parts as $part) {
-                if (!preg_match($pattern, $part) || in_array($part, $reserved, true)) {
+                if (!preg_match($pattern, $part) || \in_array($part, $reserved, true)) {
                     throw new \InvalidArgumentException('The callback name is not valid.');
                 }
             }
@@ -142,7 +142,7 @@ class JsonResponse extends Response
         try {
             $data = json_encode($data, $this->encodingOptions);
         } catch (\Exception $e) {
-            if ('Exception' === get_class($e) && 0 === strpos($e->getMessage(), 'Failed calling ')) {
+            if ('Exception' === \get_class($e) && 0 === strpos($e->getMessage(), 'Failed calling ')) {
                 throw $e->getPrevious() ?: $e;
             }
             throw $e;
diff --git a/src/Symfony/Component/HttpFoundation/ParameterBag.php b/src/Symfony/Component/HttpFoundation/ParameterBag.php
index 257ef8bcea..e3be0a9b8b 100644
--- a/src/Symfony/Component/HttpFoundation/ParameterBag.php
+++ b/src/Symfony/Component/HttpFoundation/ParameterBag.php
@@ -200,12 +200,12 @@ class ParameterBag implements \IteratorAggregate, \Countable
         $value = $this->get($key, $default);
 
         // Always turn $options into an array - this allows filter_var option shortcuts.
-        if (!is_array($options) && $options) {
+        if (!\is_array($options) && $options) {
             $options = array('flags' => $options);
         }
 
         // Add a convenience check for arrays.
-        if (is_array($value) && !isset($options['flags'])) {
+        if (\is_array($value) && !isset($options['flags'])) {
             $options['flags'] = FILTER_REQUIRE_ARRAY;
         }
 
@@ -229,6 +229,6 @@ class ParameterBag implements \IteratorAggregate, \Countable
      */
     public function count()
     {
-        return count($this->parameters);
+        return \count($this->parameters);
     }
 }
diff --git a/src/Symfony/Component/HttpFoundation/Request.php b/src/Symfony/Component/HttpFoundation/Request.php
index a051fc6167..3f3b499b89 100644
--- a/src/Symfony/Component/HttpFoundation/Request.php
+++ b/src/Symfony/Component/HttpFoundation/Request.php
@@ -287,7 +287,7 @@ class Request
         $request = self::createRequestFromFactory($_GET, $_POST, array(), $_COOKIE, $_FILES, $_SERVER);
 
         if (0 === strpos($request->headers->get('CONTENT_TYPE'), 'application/x-www-form-urlencoded')
-            && in_array(strtoupper($request->server->get('REQUEST_METHOD', 'GET')), array('PUT', 'DELETE', 'PATCH'))
+            && \in_array(strtoupper($request->server->get('REQUEST_METHOD', 'GET')), array('PUT', 'DELETE', 'PATCH'))
         ) {
             parse_str($request->getContent(), $data);
             $request->request = new ParameterBag($data);
@@ -540,7 +540,7 @@ class Request
 
         foreach ($this->headers->all() as $key => $value) {
             $key = strtoupper(str_replace('-', '_', $key));
-            if (in_array($key, array('CONTENT_TYPE', 'CONTENT_LENGTH'))) {
+            if (\in_array($key, array('CONTENT_TYPE', 'CONTENT_LENGTH'))) {
                 $_SERVER[$key] = implode(', ', $value);
             } else {
                 $_SERVER['HTTP_'.$key] = implode(', ', $value);
@@ -1079,7 +1079,7 @@ class Request
         }
 
         $targetDirs[] = $targetFile;
-        $path = str_repeat('../', count($sourceDirs)).implode('/', $targetDirs);
+        $path = str_repeat('../', \count($sourceDirs)).implode('/', $targetDirs);
 
         // A reference to the same base directory or an empty subdirectory must be prefixed with "./".
         // This also applies to a segment with a colon character (e.g., "file:colon") that cannot be used
@@ -1118,7 +1118,7 @@ class Request
     public function isSecure()
     {
         if ($this->isFromTrustedProxy() && $proto = $this->getTrustedValues(self::HEADER_X_FORWARDED_PROTO)) {
-            return in_array(strtolower($proto[0]), array('https', 'on', 'ssl', '1'), true);
+            return \in_array(strtolower($proto[0]), array('https', 'on', 'ssl', '1'), true);
         }
 
         $https = $this->server->get('HTTPS');
@@ -1164,10 +1164,10 @@ class Request
             throw new SuspiciousOperationException(sprintf('Invalid Host "%s".', $host));
         }
 
-        if (count(self::$trustedHostPatterns) > 0) {
+        if (\count(self::$trustedHostPatterns) > 0) {
             // to avoid host header injection attacks, you should provide a list of trusted host patterns
 
-            if (in_array($host, self::$trustedHosts)) {
+            if (\in_array($host, self::$trustedHosts)) {
                 return $host;
             }
 
@@ -1296,10 +1296,10 @@ class Request
         }
 
         foreach (static::$formats as $format => $mimeTypes) {
-            if (in_array($mimeType, (array) $mimeTypes)) {
+            if (\in_array($mimeType, (array) $mimeTypes)) {
                 return $format;
             }
-            if (null !== $canonicalMimeType && in_array($canonicalMimeType, (array) $mimeTypes)) {
+            if (null !== $canonicalMimeType && \in_array($canonicalMimeType, (array) $mimeTypes)) {
                 return $format;
             }
         }
@@ -1317,7 +1317,7 @@ class Request
             static::initializeFormats();
         }
 
-        static::$formats[$format] = is_array($mimeTypes) ? $mimeTypes : array($mimeTypes);
+        static::$formats[$format] = \is_array($mimeTypes) ? $mimeTypes : array($mimeTypes);
     }
 
     /**
@@ -1441,12 +1441,12 @@ class Request
      */
     public function isMethodSafe(/* $andCacheable = true */)
     {
-        if (!func_num_args() || func_get_arg(0)) {
+        if (!\func_num_args() || func_get_arg(0)) {
             // setting $andCacheable to false should be deprecated in 4.1
             throw new \BadMethodCallException('Checking only for cacheable HTTP methods with Symfony\Component\HttpFoundation\Request::isMethodSafe() is not supported.');
         }
 
-        return in_array($this->getMethod(), array('GET', 'HEAD', 'OPTIONS', 'TRACE'));
+        return \in_array($this->getMethod(), array('GET', 'HEAD', 'OPTIONS', 'TRACE'));
     }
 
     /**
@@ -1456,7 +1456,7 @@ class Request
      */
     public function isMethodIdempotent()
     {
-        return in_array($this->getMethod(), array('HEAD', 'GET', 'PUT', 'DELETE', 'TRACE', 'OPTIONS', 'PURGE'));
+        return \in_array($this->getMethod(), array('HEAD', 'GET', 'PUT', 'DELETE', 'TRACE', 'OPTIONS', 'PURGE'));
     }
 
     /**
@@ -1468,7 +1468,7 @@ class Request
      */
     public function isMethodCacheable()
     {
-        return in_array($this->getMethod(), array('GET', 'HEAD'));
+        return \in_array($this->getMethod(), array('GET', 'HEAD'));
     }
 
     /**
@@ -1506,7 +1506,7 @@ class Request
      */
     public function getContent($asResource = false)
     {
-        $currentContentIsResource = is_resource($this->content);
+        $currentContentIsResource = \is_resource($this->content);
 
         if (true === $asResource) {
             if ($currentContentIsResource) {
@@ -1516,7 +1516,7 @@ class Request
             }
 
             // Content passed in parameter (test)
-            if (is_string($this->content)) {
+            if (\is_string($this->content)) {
                 $resource = fopen('php://temp', 'r+');
                 fwrite($resource, $this->content);
                 rewind($resource);
@@ -1584,7 +1584,7 @@ class Request
             $extendedPreferredLanguages[] = $language;
             if (false !== $position = strpos($language, '_')) {
                 $superLanguage = substr($language, 0, $position);
-                if (!in_array($superLanguage, $preferredLanguages)) {
+                if (!\in_array($superLanguage, $preferredLanguages)) {
                     $extendedPreferredLanguages[] = $superLanguage;
                 }
             }
@@ -1615,11 +1615,11 @@ class Request
                     // Language not listed in ISO 639 that are not variants
                     // of any listed language, which can be registered with the
                     // i-prefix, such as i-cherokee
-                    if (count($codes) > 1) {
+                    if (\count($codes) > 1) {
                         $lang = $codes[1];
                     }
                 } else {
-                    for ($i = 0, $max = count($codes); $i < $max; ++$i) {
+                    for ($i = 0, $max = \count($codes); $i < $max; ++$i) {
                         if (0 === $i) {
                             $lang = strtolower($codes[0]);
                         } else {
@@ -1725,7 +1725,7 @@ class Request
             // HTTP proxy reqs setup request URI with scheme and host [and port] + the URL path, only use URL path
             $schemeAndHttpHost = $this->getSchemeAndHttpHost();
             if (0 === strpos($requestUri, $schemeAndHttpHost)) {
-                $requestUri = substr($requestUri, strlen($schemeAndHttpHost));
+                $requestUri = substr($requestUri, \strlen($schemeAndHttpHost));
             }
         } elseif ($this->server->has('ORIG_PATH_INFO')) {
             // IIS 5.0, PHP as CGI
@@ -1765,7 +1765,7 @@ class Request
             $segs = explode('/', trim($file, '/'));
             $segs = array_reverse($segs);
             $index = 0;
-            $last = count($segs);
+            $last = \count($segs);
             $baseUrl = '';
             do {
                 $seg = $segs[$index];
@@ -1785,7 +1785,7 @@ class Request
             return $prefix;
         }
 
-        if ($baseUrl && false !== $prefix = $this->getUrlencodedPrefix($requestUri, rtrim(dirname($baseUrl), '/'.DIRECTORY_SEPARATOR).'/')) {
+        if ($baseUrl && false !== $prefix = $this->getUrlencodedPrefix($requestUri, rtrim(\dirname($baseUrl), '/'.DIRECTORY_SEPARATOR).'/')) {
             // directory portion of $baseUrl matches
             return rtrim($prefix, '/'.DIRECTORY_SEPARATOR);
         }
@@ -1804,8 +1804,8 @@ class Request
         // If using mod_rewrite or ISAPI_Rewrite strip the script filename
         // out of baseUrl. $pos !== 0 makes sure it is not matching a value
         // from PATH_INFO or QUERY_STRING
-        if (strlen($requestUri) >= strlen($baseUrl) && (false !== $pos = strpos($requestUri, $baseUrl)) && 0 !== $pos) {
-            $baseUrl = substr($requestUri, 0, $pos + strlen($baseUrl));
+        if (\strlen($requestUri) >= \strlen($baseUrl) && (false !== $pos = strpos($requestUri, $baseUrl)) && 0 !== $pos) {
+            $baseUrl = substr($requestUri, 0, $pos + \strlen($baseUrl));
         }
 
         return rtrim($baseUrl, '/'.DIRECTORY_SEPARATOR);
@@ -1825,7 +1825,7 @@ class Request
 
         $filename = basename($this->server->get('SCRIPT_FILENAME'));
         if (basename($baseUrl) === $filename) {
-            $basePath = dirname($baseUrl);
+            $basePath = \dirname($baseUrl);
         } else {
             $basePath = $baseUrl;
         }
@@ -1860,7 +1860,7 @@ class Request
             return $requestUri;
         }
 
-        $pathInfo = substr($requestUri, strlen($baseUrl));
+        $pathInfo = substr($requestUri, \strlen($baseUrl));
         if (false === $pathInfo || '' === $pathInfo) {
             // If substr() returns false then PATH_INFO is set to an empty string
             return '/';
@@ -1914,7 +1914,7 @@ class Request
             return false;
         }
 
-        $len = strlen($prefix);
+        $len = \strlen($prefix);
 
         if (preg_match(sprintf('#^(%%[[:xdigit:]]{2}|.){%d}#', $len), $string, $match)) {
             return $match[0];
@@ -1926,7 +1926,7 @@ class Request
     private static function createRequestFromFactory(array $query = array(), array $request = array(), array $attributes = array(), array $cookies = array(), array $files = array(), array $server = array(), $content = null)
     {
         if (self::$requestFactory) {
-            $request = call_user_func(self::$requestFactory, $query, $request, $attributes, $cookies, $files, $server, $content);
+            $request = \call_user_func(self::$requestFactory, $query, $request, $attributes, $cookies, $files, $server, $content);
 
             if (!$request instanceof self) {
                 throw new \LogicException('The Request factory must return an instance of Symfony\Component\HttpFoundation\Request.');
diff --git a/src/Symfony/Component/HttpFoundation/RequestMatcher.php b/src/Symfony/Component/HttpFoundation/RequestMatcher.php
index cc13f71af2..57fa48e40b 100644
--- a/src/Symfony/Component/HttpFoundation/RequestMatcher.php
+++ b/src/Symfony/Component/HttpFoundation/RequestMatcher.php
@@ -145,11 +145,11 @@ class RequestMatcher implements RequestMatcherInterface
      */
     public function matches(Request $request)
     {
-        if ($this->schemes && !in_array($request->getScheme(), $this->schemes, true)) {
+        if ($this->schemes && !\in_array($request->getScheme(), $this->schemes, true)) {
             return false;
         }
 
-        if ($this->methods && !in_array($request->getMethod(), $this->methods, true)) {
+        if ($this->methods && !\in_array($request->getMethod(), $this->methods, true)) {
             return false;
         }
 
@@ -173,6 +173,6 @@ class RequestMatcher implements RequestMatcherInterface
 
         // Note to future implementors: add additional checks above the
         // foreach above or else your check might not be run!
-        return 0 === count($this->ips);
+        return 0 === \count($this->ips);
     }
 }
diff --git a/src/Symfony/Component/HttpFoundation/RequestStack.php b/src/Symfony/Component/HttpFoundation/RequestStack.php
index 3d9cfd0c64..40123f66f9 100644
--- a/src/Symfony/Component/HttpFoundation/RequestStack.php
+++ b/src/Symfony/Component/HttpFoundation/RequestStack.php
@@ -92,7 +92,7 @@ class RequestStack
      */
     public function getParentRequest()
     {
-        $pos = count($this->requests) - 2;
+        $pos = \count($this->requests) - 2;
 
         if (!isset($this->requests[$pos])) {
             return;
diff --git a/src/Symfony/Component/HttpFoundation/Response.php b/src/Symfony/Component/HttpFoundation/Response.php
index b7433173c7..57776d0cc6 100644
--- a/src/Symfony/Component/HttpFoundation/Response.php
+++ b/src/Symfony/Component/HttpFoundation/Response.php
@@ -368,7 +368,7 @@ class Response
         $this->sendHeaders();
         $this->sendContent();
 
-        if (function_exists('fastcgi_finish_request')) {
+        if (\function_exists('fastcgi_finish_request')) {
             fastcgi_finish_request();
         } elseif (!\in_array(PHP_SAPI, array('cli', 'phpdbg'), true)) {
             static::closeOutputBuffers(0, true);
@@ -390,8 +390,8 @@ class Response
      */
     public function setContent($content)
     {
-        if (null !== $content && !is_string($content) && !is_numeric($content) && !is_callable(array($content, '__toString'))) {
-            throw new \UnexpectedValueException(sprintf('The Response content must be a string or object implementing __toString(), "%s" given.', gettype($content)));
+        if (null !== $content && !\is_string($content) && !is_numeric($content) && !\is_callable(array($content, '__toString'))) {
+            throw new \UnexpectedValueException(sprintf('The Response content must be a string or object implementing __toString(), "%s" given.', \gettype($content)));
         }
 
         $this->content = (string) $content;
@@ -522,7 +522,7 @@ class Response
      */
     public function isCacheable(): bool
     {
-        if (!in_array($this->statusCode, array(200, 203, 300, 301, 302, 404, 410))) {
+        if (!\in_array($this->statusCode, array(200, 203, 300, 301, 302, 404, 410))) {
             return false;
         }
 
@@ -1067,7 +1067,7 @@ class Response
         $modifiedSince = $request->headers->get('If-Modified-Since');
 
         if ($etags = $request->getETags()) {
-            $notModified = in_array($this->getEtag(), $etags) || in_array('*', $etags);
+            $notModified = \in_array($this->getEtag(), $etags) || \in_array('*', $etags);
         }
 
         if ($modifiedSince && $lastModified) {
@@ -1180,7 +1180,7 @@ class Response
      */
     public function isRedirect(string $location = null): bool
     {
-        return in_array($this->statusCode, array(201, 301, 302, 303, 307, 308)) && (null === $location ?: $location == $this->headers->get('Location'));
+        return \in_array($this->statusCode, array(201, 301, 302, 303, 307, 308)) && (null === $location ?: $location == $this->headers->get('Location'));
     }
 
     /**
@@ -1190,7 +1190,7 @@ class Response
      */
     public function isEmpty(): bool
     {
-        return in_array($this->statusCode, array(204, 304));
+        return \in_array($this->statusCode, array(204, 304));
     }
 
     /**
@@ -1203,7 +1203,7 @@ class Response
     public static function closeOutputBuffers(int $targetLevel, bool $flush)
     {
         $status = ob_get_status(true);
-        $level = count($status);
+        $level = \count($status);
         $flags = PHP_OUTPUT_HANDLER_REMOVABLE | ($flush ? PHP_OUTPUT_HANDLER_FLUSHABLE : PHP_OUTPUT_HANDLER_CLEANABLE);
 
         while ($level-- > $targetLevel && ($s = $status[$level]) && (!isset($s['del']) ? !isset($s['flags']) || ($s['flags'] & $flags) === $flags : $s['del'])) {
diff --git a/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php b/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php
index 2f1abf5846..ed2e0cfb57 100644
--- a/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php
+++ b/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php
@@ -216,7 +216,7 @@ class ResponseHeaderBag extends HeaderBag
      */
     public function getCookies($format = self::COOKIES_FLAT)
     {
-        if (!in_array($format, array(self::COOKIES_FLAT, self::COOKIES_ARRAY))) {
+        if (!\in_array($format, array(self::COOKIES_FLAT, self::COOKIES_ARRAY))) {
             throw new \InvalidArgumentException(sprintf('Format "%s" invalid (%s).', $format, implode(', ', array(self::COOKIES_FLAT, self::COOKIES_ARRAY))));
         }
 
@@ -267,7 +267,7 @@ class ResponseHeaderBag extends HeaderBag
      */
     public function makeDisposition($disposition, $filename, $filenameFallback = '')
     {
-        if (!in_array($disposition, array(self::DISPOSITION_ATTACHMENT, self::DISPOSITION_INLINE))) {
+        if (!\in_array($disposition, array(self::DISPOSITION_ATTACHMENT, self::DISPOSITION_INLINE))) {
             throw new \InvalidArgumentException(sprintf('The disposition must be either "%s" or "%s".', self::DISPOSITION_ATTACHMENT, self::DISPOSITION_INLINE));
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/ServerBag.php b/src/Symfony/Component/HttpFoundation/ServerBag.php
index 19d2022ef7..d8ab561aaf 100644
--- a/src/Symfony/Component/HttpFoundation/ServerBag.php
+++ b/src/Symfony/Component/HttpFoundation/ServerBag.php
@@ -68,7 +68,7 @@ class ServerBag extends ParameterBag
                 if (0 === stripos($authorizationHeader, 'basic ')) {
                     // Decode AUTHORIZATION header into PHP_AUTH_USER and PHP_AUTH_PW when authorization header is basic
                     $exploded = explode(':', base64_decode(substr($authorizationHeader, 6)), 2);
-                    if (2 == count($exploded)) {
+                    if (2 == \count($exploded)) {
                         list($headers['PHP_AUTH_USER'], $headers['PHP_AUTH_PW']) = $exploded;
                     }
                 } elseif (empty($this->parameters['PHP_AUTH_DIGEST']) && (0 === stripos($authorizationHeader, 'digest '))) {
diff --git a/src/Symfony/Component/HttpFoundation/Session/Attribute/AttributeBag.php b/src/Symfony/Component/HttpFoundation/Session/Attribute/AttributeBag.php
index 286534b8f2..82577b804e 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Attribute/AttributeBag.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Attribute/AttributeBag.php
@@ -143,6 +143,6 @@ class AttributeBag implements AttributeBagInterface, \IteratorAggregate, \Counta
      */
     public function count()
     {
-        return count($this->attributes);
+        return \count($this->attributes);
     }
 }
diff --git a/src/Symfony/Component/HttpFoundation/Session/Attribute/NamespacedAttributeBag.php b/src/Symfony/Component/HttpFoundation/Session/Attribute/NamespacedAttributeBag.php
index dd7a7fad82..50cd740d95 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Attribute/NamespacedAttributeBag.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Attribute/NamespacedAttributeBag.php
@@ -110,7 +110,7 @@ class NamespacedAttributeBag extends AttributeBag
         }
 
         $parts = explode($this->namespaceCharacter, $name);
-        if (count($parts) < 2) {
+        if (\count($parts) < 2) {
             if (!$writeContext) {
                 return $array;
             }
@@ -120,7 +120,7 @@ class NamespacedAttributeBag extends AttributeBag
             return $array;
         }
 
-        unset($parts[count($parts) - 1]);
+        unset($parts[\count($parts) - 1]);
 
         foreach ($parts as $part) {
             if (null !== $array && !array_key_exists($part, $array)) {
diff --git a/src/Symfony/Component/HttpFoundation/Session/Session.php b/src/Symfony/Component/HttpFoundation/Session/Session.php
index c0978d552f..a89bad672b 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Session.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Session.php
@@ -138,7 +138,7 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     public function count()
     {
-        return count($this->getAttributeBag()->all());
+        return \count($this->getAttributeBag()->all());
     }
 
     /**
diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/AbstractSessionHandler.php b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/AbstractSessionHandler.php
index 1d3500a995..b1465716cb 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/AbstractSessionHandler.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/AbstractSessionHandler.php
@@ -119,7 +119,7 @@ abstract class AbstractSessionHandler implements \SessionHandlerInterface, \Sess
     {
         if (!headers_sent() && ini_get('session.use_cookies')) {
             if (!$this->sessionName) {
-                throw new \LogicException(sprintf('Session name cannot be empty, did you forget to call "parent::open()" in "%s"?.', get_class($this)));
+                throw new \LogicException(sprintf('Session name cannot be empty, did you forget to call "parent::open()" in "%s"?.', \get_class($this)));
             }
             $sessionCookie = sprintf(' %s=', urlencode($this->sessionName));
             $sessionCookieWithId = sprintf('%s%s;', $sessionCookie, urlencode($sessionId));
diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/PdoSessionHandler.php b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/PdoSessionHandler.php
index 0fd34dc1b6..d1e4516715 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/PdoSessionHandler.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/PdoSessionHandler.php
@@ -178,7 +178,7 @@ class PdoSessionHandler extends AbstractSessionHandler
 
             $this->pdo = $pdoOrDsn;
             $this->driver = $this->pdo->getAttribute(\PDO::ATTR_DRIVER_NAME);
-        } elseif (is_string($pdoOrDsn) && false !== strpos($pdoOrDsn, '://')) {
+        } elseif (\is_string($pdoOrDsn) && false !== strpos($pdoOrDsn, '://')) {
             $this->dsn = $this->buildDsnFromUrl($pdoOrDsn);
         } else {
             $this->dsn = $pdoOrDsn;
@@ -629,7 +629,7 @@ class PdoSessionHandler extends AbstractSessionHandler
                     return '';
                 }
 
-                return is_resource($sessionRows[0][0]) ? stream_get_contents($sessionRows[0][0]) : $sessionRows[0][0];
+                return \is_resource($sessionRows[0][0]) ? stream_get_contents($sessionRows[0][0]) : $sessionRows[0][0];
             }
 
             if (null !== $insertStmt) {
@@ -735,11 +735,11 @@ class PdoSessionHandler extends AbstractSessionHandler
     private function convertStringToInt(string $string): int
     {
         if (4 === \PHP_INT_SIZE) {
-            return (ord($string[3]) << 24) + (ord($string[2]) << 16) + (ord($string[1]) << 8) + ord($string[0]);
+            return (\ord($string[3]) << 24) + (\ord($string[2]) << 16) + (\ord($string[1]) << 8) + \ord($string[0]);
         }
 
-        $int1 = (ord($string[7]) << 24) + (ord($string[6]) << 16) + (ord($string[5]) << 8) + ord($string[4]);
-        $int2 = (ord($string[3]) << 24) + (ord($string[2]) << 16) + (ord($string[1]) << 8) + ord($string[0]);
+        $int1 = (\ord($string[7]) << 24) + (\ord($string[6]) << 16) + (\ord($string[5]) << 8) + \ord($string[4]);
+        $int2 = (\ord($string[3]) << 24) + (\ord($string[2]) << 16) + (\ord($string[1]) << 8) + \ord($string[0]);
 
         return $int2 + ($int1 << 32);
     }
diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/RedisSessionHandler.php b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/RedisSessionHandler.php
index bad59332a9..0598362395 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/RedisSessionHandler.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/RedisSessionHandler.php
@@ -41,7 +41,7 @@ class RedisSessionHandler extends AbstractSessionHandler
     public function __construct($redis, array $options = array())
     {
         if (!$redis instanceof \Redis && !$redis instanceof \RedisArray && !$redis instanceof \Predis\Client && !$redis instanceof RedisProxy) {
-            throw new \InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, is_object($redis) ? get_class($redis) : gettype($redis)));
+            throw new \InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, \is_object($redis) ? \get_class($redis) : \gettype($redis)));
         }
 
         if ($diff = array_diff(array_keys($options), array('prefix'))) {
diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/StrictSessionHandler.php b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/StrictSessionHandler.php
index 228119297d..83a1f2c063 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/StrictSessionHandler.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Storage/Handler/StrictSessionHandler.php
@@ -24,7 +24,7 @@ class StrictSessionHandler extends AbstractSessionHandler
     public function __construct(\SessionHandlerInterface $handler)
     {
         if ($handler instanceof \SessionUpdateTimestampHandlerInterface) {
-            throw new \LogicException(sprintf('"%s" is already an instance of "SessionUpdateTimestampHandlerInterface", you cannot wrap it with "%s".', get_class($handler), self::class));
+            throw new \LogicException(sprintf('"%s" is already an instance of "SessionUpdateTimestampHandlerInterface", you cannot wrap it with "%s".', \get_class($handler), self::class));
         }
 
         $this->handler = $handler;
diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php b/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
index bfe13f05ed..bf54f19e3f 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
@@ -248,7 +248,7 @@ class NativeSessionStorage implements SessionStorageInterface
                 $handler = $handler->getHandler();
             }
 
-            trigger_error(sprintf('session_write_close(): Failed to write session data with %s handler', get_class($handler)), E_USER_WARNING);
+            trigger_error(sprintf('session_write_close(): Failed to write session data with %s handler', \get_class($handler)), E_USER_WARNING);
         }
 
         $this->closed = true;
diff --git a/src/Symfony/Component/HttpFoundation/StreamedResponse.php b/src/Symfony/Component/HttpFoundation/StreamedResponse.php
index 2519f874cc..6dba703d28 100644
--- a/src/Symfony/Component/HttpFoundation/StreamedResponse.php
+++ b/src/Symfony/Component/HttpFoundation/StreamedResponse.php
@@ -111,7 +111,7 @@ class StreamedResponse extends Response
             throw new \LogicException('The Response callback must not be null.');
         }
 
-        call_user_func($this->callback);
+        \call_user_func($this->callback);
 
         return $this;
     }
diff --git a/src/Symfony/Component/HttpFoundation/Tests/File/UploadedFileTest.php b/src/Symfony/Component/HttpFoundation/Tests/File/UploadedFileTest.php
index 9ba22735ec..6a0b550d79 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/File/UploadedFileTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/File/UploadedFileTest.php
@@ -53,7 +53,7 @@ class UploadedFileTest extends TestCase
 
         $this->assertEquals('application/octet-stream', $file->getClientMimeType());
 
-        if (extension_loaded('fileinfo')) {
+        if (\extension_loaded('fileinfo')) {
             $this->assertEquals('image/gif', $file->getMimeType());
         }
     }
diff --git a/src/Symfony/Component/HttpFoundation/Tests/HeaderBagTest.php b/src/Symfony/Component/HttpFoundation/Tests/HeaderBagTest.php
index 6d19ceb009..c5a437f999 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/HeaderBagTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/HeaderBagTest.php
@@ -192,7 +192,7 @@ class HeaderBagTest extends TestCase
             $this->assertEquals(array($headers[$key]), $val);
         }
 
-        $this->assertEquals(count($headers), $i);
+        $this->assertEquals(\count($headers), $i);
     }
 
     public function testCount()
@@ -200,6 +200,6 @@ class HeaderBagTest extends TestCase
         $headers = array('foo' => 'bar', 'HELLO' => 'WORLD');
         $headerBag = new HeaderBag($headers);
 
-        $this->assertCount(count($headers), $headerBag);
+        $this->assertCount(\count($headers), $headerBag);
     }
 }
diff --git a/src/Symfony/Component/HttpFoundation/Tests/IpUtilsTest.php b/src/Symfony/Component/HttpFoundation/Tests/IpUtilsTest.php
index 7a93f99472..232a2040ff 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/IpUtilsTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/IpUtilsTest.php
@@ -47,7 +47,7 @@ class IpUtilsTest extends TestCase
      */
     public function testIpv6($matches, $remoteAddr, $cidr)
     {
-        if (!defined('AF_INET6')) {
+        if (!\defined('AF_INET6')) {
             $this->markTestSkipped('Only works when PHP is compiled without the option "disable-ipv6".');
         }
 
@@ -78,7 +78,7 @@ class IpUtilsTest extends TestCase
      */
     public function testAnIpv6WithOptionDisabledIpv6()
     {
-        if (defined('AF_INET6')) {
+        if (\defined('AF_INET6')) {
             $this->markTestSkipped('Only works when PHP is compiled with the option "disable-ipv6".');
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/Tests/ParameterBagTest.php b/src/Symfony/Component/HttpFoundation/Tests/ParameterBagTest.php
index ab908d8d37..dccfd4f308 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/ParameterBagTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/ParameterBagTest.php
@@ -171,7 +171,7 @@ class ParameterBagTest extends TestCase
             $this->assertEquals($parameters[$key], $val);
         }
 
-        $this->assertEquals(count($parameters), $i);
+        $this->assertEquals(\count($parameters), $i);
     }
 
     public function testCount()
@@ -179,7 +179,7 @@ class ParameterBagTest extends TestCase
         $parameters = array('foo' => 'bar', 'hello' => 'world');
         $bag = new ParameterBag($parameters);
 
-        $this->assertCount(count($parameters), $bag);
+        $this->assertCount(\count($parameters), $bag);
     }
 
     public function testGetBoolean()
diff --git a/src/Symfony/Component/HttpFoundation/Tests/ResponseTest.php b/src/Symfony/Component/HttpFoundation/Tests/ResponseTest.php
index a51b954fa0..29cf71240d 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/ResponseTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/ResponseTest.php
@@ -974,7 +974,7 @@ class ResponseTest extends ResponseTestCase
      */
     public function ianaCodesReasonPhrasesProvider()
     {
-        if (!in_array('https', stream_get_wrappers(), true)) {
+        if (!\in_array('https', stream_get_wrappers(), true)) {
             $this->markTestSkipped('The "https" wrapper is not available');
         }
 
@@ -1002,7 +1002,7 @@ class ResponseTest extends ResponseTestCase
             $value = $xpath->query('.//ns:value', $record)->item(0)->nodeValue;
             $description = $xpath->query('.//ns:description', $record)->item(0)->nodeValue;
 
-            if (in_array($description, array('Unassigned', '(Unused)'), true)) {
+            if (\in_array($description, array('Unassigned', '(Unused)'), true)) {
                 continue;
             }
 
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Attribute/AttributeBagTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Attribute/AttributeBagTest.php
index 724a0b9844..43644e23ea 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Attribute/AttributeBagTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Attribute/AttributeBagTest.php
@@ -176,11 +176,11 @@ class AttributeBagTest extends TestCase
             ++$i;
         }
 
-        $this->assertEquals(count($this->array), $i);
+        $this->assertEquals(\count($this->array), $i);
     }
 
     public function testCount()
     {
-        $this->assertCount(count($this->array), $this->bag);
+        $this->assertCount(\count($this->array), $this->bag);
     }
 }
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php
index 41720e4b6f..f2a153a7fc 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php
@@ -206,7 +206,7 @@ class SessionTest extends TestCase
             ++$i;
         }
 
-        $this->assertEquals(count($attributes), $i);
+        $this->assertEquals(\count($attributes), $i);
     }
 
     public function testGetCount()
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/AbstractRedisSessionHandlerTestCase.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/AbstractRedisSessionHandlerTestCase.php
index dd72525f5d..bcf622e6db 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/AbstractRedisSessionHandlerTestCase.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/AbstractRedisSessionHandlerTestCase.php
@@ -46,7 +46,7 @@ abstract class AbstractRedisSessionHandlerTestCase extends TestCase
     {
         parent::setUp();
 
-        if (!extension_loaded('redis')) {
+        if (!\extension_loaded('redis')) {
             self::markTestSkipped('Extension redis required.');
         }
 
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php
index d9d0efe941..e84781898b 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/Handler/PdoSessionHandlerTest.php
@@ -389,8 +389,8 @@ class MockPdo extends \PDO
 
     public function prepare($statement, $driverOptions = array())
     {
-        return is_callable($this->prepareResult)
-            ? call_user_func($this->prepareResult, $statement, $driverOptions)
+        return \is_callable($this->prepareResult)
+            ? \call_user_func($this->prepareResult, $statement, $driverOptions)
             : $this->prepareResult;
     }
 
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php
index 382707b0c3..52da2947cb 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php
@@ -184,7 +184,7 @@ class NativeSessionStorageTest extends TestCase
 
     public function testSessionOptions()
     {
-        if (defined('HHVM_VERSION')) {
+        if (\defined('HHVM_VERSION')) {
             $this->markTestSkipped('HHVM is not handled in this test case.');
         }
 
diff --git a/src/Symfony/Component/HttpKernel/Bundle/Bundle.php b/src/Symfony/Component/HttpKernel/Bundle/Bundle.php
index 46a0c893d8..8629f48489 100644
--- a/src/Symfony/Component/HttpKernel/Bundle/Bundle.php
+++ b/src/Symfony/Component/HttpKernel/Bundle/Bundle.php
@@ -72,7 +72,7 @@ abstract class Bundle implements BundleInterface
 
             if (null !== $extension) {
                 if (!$extension instanceof ExtensionInterface) {
-                    throw new \LogicException(sprintf('Extension %s must implement Symfony\Component\DependencyInjection\Extension\ExtensionInterface.', get_class($extension)));
+                    throw new \LogicException(sprintf('Extension %s must implement Symfony\Component\DependencyInjection\Extension\ExtensionInterface.', \get_class($extension)));
                 }
 
                 // check naming convention
@@ -120,7 +120,7 @@ abstract class Bundle implements BundleInterface
     {
         if (null === $this->path) {
             $reflected = new \ReflectionObject($this);
-            $this->path = dirname($reflected->getFileName());
+            $this->path = \dirname($reflected->getFileName());
         }
 
         return $this->path;
diff --git a/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmer.php b/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmer.php
index dba35a639a..52dc2ad2c3 100644
--- a/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmer.php
+++ b/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmer.php
@@ -20,7 +20,7 @@ abstract class CacheWarmer implements CacheWarmerInterface
 {
     protected function writeCacheFile($file, $content)
     {
-        $tmpFile = @tempnam(dirname($file), basename($file));
+        $tmpFile = @tempnam(\dirname($file), basename($file));
         if (false !== @file_put_contents($tmpFile, $content) && @rename($tmpFile, $file)) {
             @chmod($file, 0666 & ~umask());
 
diff --git a/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmerAggregate.php b/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmerAggregate.php
index 4d63804be7..171b38596f 100644
--- a/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmerAggregate.php
+++ b/src/Symfony/Component/HttpKernel/CacheWarmer/CacheWarmerAggregate.php
@@ -52,7 +52,7 @@ class CacheWarmerAggregate implements CacheWarmerInterface
     {
         if ($this->debug) {
             $collectedLogs = array();
-            $previousHandler = defined('PHPUNIT_COMPOSER_INSTALL');
+            $previousHandler = \defined('PHPUNIT_COMPOSER_INSTALL');
             $previousHandler = $previousHandler ?: set_error_handler(function ($type, $message, $file, $line) use (&$collectedLogs, &$previousHandler) {
                 if (E_USER_DEPRECATED !== $type && E_DEPRECATED !== $type) {
                     return $previousHandler ? $previousHandler($type, $message, $file, $line) : false;
@@ -68,7 +68,7 @@ class CacheWarmerAggregate implements CacheWarmerInterface
                 // Clean the trace by removing first frames added by the error handler itself.
                 for ($i = 0; isset($backtrace[$i]); ++$i) {
                     if (isset($backtrace[$i]['file'], $backtrace[$i]['line']) && $backtrace[$i]['line'] === $line && $backtrace[$i]['file'] === $file) {
-                        $backtrace = array_slice($backtrace, 1 + $i);
+                        $backtrace = \array_slice($backtrace, 1 + $i);
                         break;
                     }
                 }
diff --git a/src/Symfony/Component/HttpKernel/Client.php b/src/Symfony/Component/HttpKernel/Client.php
index 623ce34ec5..f48427387c 100644
--- a/src/Symfony/Component/HttpKernel/Client.php
+++ b/src/Symfony/Component/HttpKernel/Client.php
@@ -89,7 +89,7 @@ class Client extends BaseClient
         foreach (get_declared_classes() as $class) {
             if (0 === strpos($class, 'ComposerAutoloaderInit')) {
                 $r = new \ReflectionClass($class);
-                $file = dirname(dirname($r->getFileName())).'/autoload.php';
+                $file = \dirname(\dirname($r->getFileName())).'/autoload.php';
                 if (file_exists($file)) {
                     $requires .= "require_once '".str_replace("'", "\\'", $file)."';\n";
                 }
@@ -160,7 +160,7 @@ EOF;
     {
         $filtered = array();
         foreach ($files as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $filtered[$key] = $this->filterFiles($value);
             } elseif ($value instanceof UploadedFile) {
                 if ($value->isValid() && $value->getSize() > UploadedFile::getMaxFilesize()) {
diff --git a/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver.php b/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver.php
index 186007ebe4..142a6d54a6 100644
--- a/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver.php
+++ b/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver.php
@@ -56,7 +56,7 @@ final class ArgumentResolver implements ArgumentResolverInterface
                 $resolved = $resolver->resolve($request, $metadata);
 
                 if (!$resolved instanceof \Generator) {
-                    throw new \InvalidArgumentException(sprintf('%s::resolve() must yield at least one value.', get_class($resolver)));
+                    throw new \InvalidArgumentException(sprintf('%s::resolve() must yield at least one value.', \get_class($resolver)));
                 }
 
                 foreach ($resolved as $append) {
@@ -69,10 +69,10 @@ final class ArgumentResolver implements ArgumentResolverInterface
 
             $representative = $controller;
 
-            if (is_array($representative)) {
-                $representative = sprintf('%s::%s()', get_class($representative[0]), $representative[1]);
-            } elseif (is_object($representative)) {
-                $representative = get_class($representative);
+            if (\is_array($representative)) {
+                $representative = sprintf('%s::%s()', \get_class($representative[0]), $representative[1]);
+            } elseif (\is_object($representative)) {
+                $representative = \get_class($representative);
             }
 
             throw new \RuntimeException(sprintf('Controller "%s" requires that you provide a value for the "$%s" argument. Either the argument is nullable and no null value has been provided, no default value has been provided or because there is a non optional argument after this one.', $representative, $metadata->getName()));
diff --git a/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver/VariadicValueResolver.php b/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver/VariadicValueResolver.php
index 56ae5f191c..7ee2d7af5c 100644
--- a/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver/VariadicValueResolver.php
+++ b/src/Symfony/Component/HttpKernel/Controller/ArgumentResolver/VariadicValueResolver.php
@@ -37,8 +37,8 @@ final class VariadicValueResolver implements ArgumentValueResolverInterface
     {
         $values = $request->attributes->get($argument->getName());
 
-        if (!is_array($values)) {
-            throw new \InvalidArgumentException(sprintf('The action argument "...$%1$s" is required to be an array, the request attribute "%1$s" contains a type of "%2$s" instead.', $argument->getName(), gettype($values)));
+        if (!\is_array($values)) {
+            throw new \InvalidArgumentException(sprintf('The action argument "...$%1$s" is required to be an array, the request attribute "%1$s" contains a type of "%2$s" instead.', $argument->getName(), \gettype($values)));
         }
 
         foreach ($values as $value) {
diff --git a/src/Symfony/Component/HttpKernel/Controller/ControllerResolver.php b/src/Symfony/Component/HttpKernel/Controller/ControllerResolver.php
index dce640e31d..04c5fcf53d 100644
--- a/src/Symfony/Component/HttpKernel/Controller/ControllerResolver.php
+++ b/src/Symfony/Component/HttpKernel/Controller/ControllerResolver.php
@@ -43,8 +43,8 @@ class ControllerResolver implements ControllerResolverInterface
             return false;
         }
 
-        if (is_array($controller)) {
-            if (isset($controller[0]) && is_string($controller[0]) && isset($controller[1])) {
+        if (\is_array($controller)) {
+            if (isset($controller[0]) && \is_string($controller[0]) && isset($controller[1])) {
                 try {
                     $controller[0] = $this->instantiateController($controller[0]);
                 } catch (\Error | \LogicException $e) {
@@ -63,28 +63,28 @@ class ControllerResolver implements ControllerResolverInterface
                 }
             }
 
-            if (!is_callable($controller)) {
+            if (!\is_callable($controller)) {
                 throw new \InvalidArgumentException(sprintf('The controller for URI "%s" is not callable. %s', $request->getPathInfo(), $this->getControllerError($controller)));
             }
 
             return $controller;
         }
 
-        if (is_object($controller)) {
-            if (!is_callable($controller)) {
+        if (\is_object($controller)) {
+            if (!\is_callable($controller)) {
                 throw new \InvalidArgumentException(sprintf('The controller for URI "%s" is not callable. %s', $request->getPathInfo(), $this->getControllerError($controller)));
             }
 
             return $controller;
         }
 
-        if (function_exists($controller)) {
+        if (\function_exists($controller)) {
             return $controller;
         }
 
         $callable = $this->createController($controller);
 
-        if (!is_callable($callable)) {
+        if (!\is_callable($callable)) {
             throw new \InvalidArgumentException(sprintf('The controller for URI "%s" is not callable. %s', $request->getPathInfo(), $this->getControllerError($callable)));
         }
 
@@ -135,7 +135,7 @@ class ControllerResolver implements ControllerResolverInterface
 
     private function getControllerError($callable)
     {
-        if (is_string($callable)) {
+        if (\is_string($callable)) {
             if (false !== strpos($callable, '::')) {
                 $callable = explode('::', $callable, 2);
             } else {
@@ -143,28 +143,28 @@ class ControllerResolver implements ControllerResolverInterface
             }
         }
 
-        if (is_object($callable)) {
+        if (\is_object($callable)) {
             $availableMethods = $this->getClassMethodsWithoutMagicMethods($callable);
             $alternativeMsg = $availableMethods ? sprintf(' or use one of the available methods: "%s"', implode('", "', $availableMethods)) : '';
 
-            return sprintf('Controller class "%s" cannot be called without a method name. You need to implement "__invoke"%s.', get_class($callable), $alternativeMsg);
+            return sprintf('Controller class "%s" cannot be called without a method name. You need to implement "__invoke"%s.', \get_class($callable), $alternativeMsg);
         }
 
-        if (!is_array($callable)) {
-            return sprintf('Invalid type for controller given, expected string, array or object, got "%s".', gettype($callable));
+        if (!\is_array($callable)) {
+            return sprintf('Invalid type for controller given, expected string, array or object, got "%s".', \gettype($callable));
         }
 
-        if (!isset($callable[0]) || !isset($callable[1]) || 2 !== count($callable)) {
+        if (!isset($callable[0]) || !isset($callable[1]) || 2 !== \count($callable)) {
             return 'Invalid array callable, expected array(controller, method).';
         }
 
         list($controller, $method) = $callable;
 
-        if (is_string($controller) && !class_exists($controller)) {
+        if (\is_string($controller) && !class_exists($controller)) {
             return sprintf('Class "%s" does not exist.', $controller);
         }
 
-        $className = is_object($controller) ? get_class($controller) : $controller;
+        $className = \is_object($controller) ? \get_class($controller) : $controller;
 
         if (method_exists($controller, $method)) {
             return sprintf('Method "%s" on class "%s" should be public and non-abstract.', $method, $className);
@@ -177,7 +177,7 @@ class ControllerResolver implements ControllerResolverInterface
         foreach ($collection as $item) {
             $lev = levenshtein($method, $item);
 
-            if ($lev <= strlen($method) / 3 || false !== strpos($item, $method)) {
+            if ($lev <= \strlen($method) / 3 || false !== strpos($item, $method)) {
                 $alternatives[] = $item;
             }
         }
@@ -186,7 +186,7 @@ class ControllerResolver implements ControllerResolverInterface
 
         $message = sprintf('Expected method "%s" on class "%s"', $method, $className);
 
-        if (count($alternatives) > 0) {
+        if (\count($alternatives) > 0) {
             $message .= sprintf(', did you mean "%s"?', implode('", "', $alternatives));
         } else {
             $message .= sprintf('. Available methods: "%s".', implode('", "', $collection));
diff --git a/src/Symfony/Component/HttpKernel/ControllerMetadata/ArgumentMetadataFactory.php b/src/Symfony/Component/HttpKernel/ControllerMetadata/ArgumentMetadataFactory.php
index 86683d55de..10e851b67a 100644
--- a/src/Symfony/Component/HttpKernel/ControllerMetadata/ArgumentMetadataFactory.php
+++ b/src/Symfony/Component/HttpKernel/ControllerMetadata/ArgumentMetadataFactory.php
@@ -25,9 +25,9 @@ final class ArgumentMetadataFactory implements ArgumentMetadataFactoryInterface
     {
         $arguments = array();
 
-        if (is_array($controller)) {
+        if (\is_array($controller)) {
             $reflection = new \ReflectionMethod($controller[0], $controller[1]);
-        } elseif (is_object($controller) && !$controller instanceof \Closure) {
+        } elseif (\is_object($controller) && !$controller instanceof \Closure) {
             $reflection = (new \ReflectionObject($controller))->getMethod('__invoke');
         } else {
             $reflection = new \ReflectionFunction($controller);
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/ConfigDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/ConfigDataCollector.php
index 14abce761f..fd1d40a546 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/ConfigDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/ConfigDataCollector.php
@@ -67,9 +67,9 @@ class ConfigDataCollector extends DataCollector implements LateDataCollectorInte
             'php_architecture' => PHP_INT_SIZE * 8,
             'php_intl_locale' => class_exists('Locale', false) && \Locale::getDefault() ? \Locale::getDefault() : 'n/a',
             'php_timezone' => date_default_timezone_get(),
-            'xdebug_enabled' => extension_loaded('xdebug'),
-            'apcu_enabled' => extension_loaded('apcu') && ini_get('apc.enabled'),
-            'zend_opcache_enabled' => extension_loaded('Zend OPcache') && ini_get('opcache.enable'),
+            'xdebug_enabled' => \extension_loaded('xdebug'),
+            'apcu_enabled' => \extension_loaded('apcu') && ini_get('apc.enabled'),
+            'zend_opcache_enabled' => \extension_loaded('Zend OPcache') && ini_get('opcache.enable'),
             'bundles' => array(),
             'sapi_name' => PHP_SAPI,
         );
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php
index faa0d9e370..a3d8c99d84 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/DataCollector.php
@@ -80,7 +80,7 @@ abstract class DataCollector implements DataCollectorInterface, \Serializable
             '*' => function ($v, array $a, Stub $s, $isNested) {
                 if (!$v instanceof Stub) {
                     foreach ($a as $k => $v) {
-                        if (is_object($v) && !$v instanceof \DateTimeInterface && !$v instanceof Stub) {
+                        if (\is_object($v) && !$v instanceof \DateTimeInterface && !$v instanceof Stub) {
                             $a[$k] = new CutStub($v);
                         }
                     }
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php
index 8e43faa9dd..1b6e976c4e 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/DumpDataCollector.php
@@ -154,7 +154,7 @@ class DumpDataCollector extends DataCollector implements DataDumperInterface
         parent::unserialize($data);
         $charset = array_pop($this->data);
         $fileLinkFormat = array_pop($this->data);
-        $this->dataCount = count($this->data);
+        $this->dataCount = \count($this->data);
         self::__construct($this->stopwatch, $fileLinkFormat, $charset);
     }
 
@@ -198,7 +198,7 @@ class DumpDataCollector extends DataCollector implements DataDumperInterface
             $this->isCollected = true;
 
             $h = headers_list();
-            $i = count($h);
+            $i = \count($h);
             array_unshift($h, 'Content-Type: '.ini_get('default_mimetype'));
             while (0 !== stripos($h[$i], 'Content-Type:')) {
                 --$i;
@@ -230,7 +230,7 @@ class DumpDataCollector extends DataCollector implements DataDumperInterface
                         $s = $this->style('meta', '%s');
                         $f = strip_tags($this->style('', $file));
                         $name = strip_tags($this->style('', $name));
-                        if ($fmt && $link = is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line)) {
+                        if ($fmt && $link = \is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line)) {
                             $name = sprintf('<a href="%s" title="%s">'.$s.'</a>', strip_tags($this->style('', $link)), $f, $name);
                         } else {
                             $name = sprintf('<abbr title="%s">'.$s.'</abbr>', $f, $name);
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/LoggerDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/LoggerDataCollector.php
index 6218c0c246..533d3217b3 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/LoggerDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/LoggerDataCollector.php
@@ -223,7 +223,7 @@ class LoggerDataCollector extends DataCollector implements LateDataCollectorInte
             return true;
         }
 
-        if ($exception instanceof \ErrorException && in_array($exception->getSeverity(), array(E_DEPRECATED, E_USER_DEPRECATED), true)) {
+        if ($exception instanceof \ErrorException && \in_array($exception->getSeverity(), array(E_DEPRECATED, E_USER_DEPRECATED), true)) {
             return true;
         }
 
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/MemoryDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/MemoryDataCollector.php
index 8d8cc1a04d..310b2f91a5 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/MemoryDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/MemoryDataCollector.php
@@ -98,9 +98,9 @@ class MemoryDataCollector extends DataCollector implements LateDataCollectorInte
         $memoryLimit = strtolower($memoryLimit);
         $max = strtolower(ltrim($memoryLimit, '+'));
         if (0 === strpos($max, '0x')) {
-            $max = intval($max, 16);
+            $max = \intval($max, 16);
         } elseif (0 === strpos($max, '0')) {
-            $max = intval($max, 8);
+            $max = \intval($max, 8);
         } else {
             $max = (int) $max;
         }
diff --git a/src/Symfony/Component/HttpKernel/DataCollector/RequestDataCollector.php b/src/Symfony/Component/HttpKernel/DataCollector/RequestDataCollector.php
index ba630d66f8..a8cb015b88 100644
--- a/src/Symfony/Component/HttpKernel/DataCollector/RequestDataCollector.php
+++ b/src/Symfony/Component/HttpKernel/DataCollector/RequestDataCollector.php
@@ -42,7 +42,7 @@ class RequestDataCollector extends DataCollector implements EventSubscriberInter
         $route = '';
         foreach ($request->attributes->all() as $key => $value) {
             if ('_route' === $key) {
-                $route = is_object($value) ? $value->getPath() : $value;
+                $route = \is_object($value) ? $value->getPath() : $value;
                 $attributes[$key] = $route;
             } else {
                 $attributes[$key] = $value;
@@ -136,7 +136,7 @@ class RequestDataCollector extends DataCollector implements EventSubscriberInter
         }
 
         foreach ($this->data as $key => $value) {
-            if (!is_array($value)) {
+            if (!\is_array($value)) {
                 continue;
             }
             if ('request_headers' === $key || 'response_headers' === $key) {
@@ -169,7 +169,7 @@ class RequestDataCollector extends DataCollector implements EventSubscriberInter
             ));
         }
 
-        $this->data['identifier'] = $this->data['route'] ?: (is_array($this->data['controller']) ? $this->data['controller']['class'].'::'.$this->data['controller']['method'].'()' : $this->data['controller']);
+        $this->data['identifier'] = $this->data['route'] ?: (\is_array($this->data['controller']) ? $this->data['controller']['class'].'::'.$this->data['controller']['method'].'()' : $this->data['controller']);
 
         if ($response->headers->has('x-previous-debug-token')) {
             $this->data['forward_token'] = $response->headers->get('x-previous-debug-token');
@@ -389,25 +389,25 @@ class RequestDataCollector extends DataCollector implements EventSubscriberInter
      */
     protected function parseController($controller)
     {
-        if (is_string($controller) && false !== strpos($controller, '::')) {
+        if (\is_string($controller) && false !== strpos($controller, '::')) {
             $controller = explode('::', $controller);
         }
 
-        if (is_array($controller)) {
+        if (\is_array($controller)) {
             try {
                 $r = new \ReflectionMethod($controller[0], $controller[1]);
 
                 return array(
-                    'class' => is_object($controller[0]) ? get_class($controller[0]) : $controller[0],
+                    'class' => \is_object($controller[0]) ? \get_class($controller[0]) : $controller[0],
                     'method' => $controller[1],
                     'file' => $r->getFileName(),
                     'line' => $r->getStartLine(),
                 );
             } catch (\ReflectionException $e) {
-                if (is_callable($controller)) {
+                if (\is_callable($controller)) {
                     // using __call or  __callStatic
                     return array(
-                        'class' => is_object($controller[0]) ? get_class($controller[0]) : $controller[0],
+                        'class' => \is_object($controller[0]) ? \get_class($controller[0]) : $controller[0],
                         'method' => $controller[1],
                         'file' => 'n/a',
                         'line' => 'n/a',
@@ -427,7 +427,7 @@ class RequestDataCollector extends DataCollector implements EventSubscriberInter
             );
         }
 
-        if (is_object($controller)) {
+        if (\is_object($controller)) {
             $r = new \ReflectionClass($controller);
 
             return array(
@@ -438,6 +438,6 @@ class RequestDataCollector extends DataCollector implements EventSubscriberInter
             );
         }
 
-        return is_string($controller) ? $controller : 'n/a';
+        return \is_string($controller) ? $controller : 'n/a';
     }
 }
diff --git a/src/Symfony/Component/HttpKernel/Debug/FileLinkFormatter.php b/src/Symfony/Component/HttpKernel/Debug/FileLinkFormatter.php
index a4aa6c79ac..b70d4c642f 100644
--- a/src/Symfony/Component/HttpKernel/Debug/FileLinkFormatter.php
+++ b/src/Symfony/Component/HttpKernel/Debug/FileLinkFormatter.php
@@ -34,8 +34,8 @@ class FileLinkFormatter implements \Serializable
     public function __construct($fileLinkFormat = null, RequestStack $requestStack = null, string $baseDir = null, $urlFormat = null)
     {
         $fileLinkFormat = $fileLinkFormat ?: ini_get('xdebug.file_link_format') ?: get_cfg_var('xdebug.file_link_format');
-        if ($fileLinkFormat && !is_array($fileLinkFormat)) {
-            $i = strpos($f = $fileLinkFormat, '&', max(strrpos($f, '%f'), strrpos($f, '%l'))) ?: strlen($f);
+        if ($fileLinkFormat && !\is_array($fileLinkFormat)) {
+            $i = strpos($f = $fileLinkFormat, '&', max(strrpos($f, '%f'), strrpos($f, '%l'))) ?: \strlen($f);
             $fileLinkFormat = array(substr($f, 0, $i)) + preg_split('/&([^>]++)>/', substr($f, $i), -1, PREG_SPLIT_DELIM_CAPTURE);
         }
 
@@ -50,7 +50,7 @@ class FileLinkFormatter implements \Serializable
         if ($fmt = $this->getFileLinkFormat()) {
             for ($i = 1; isset($fmt[$i]); ++$i) {
                 if (0 === strpos($file, $k = $fmt[$i++])) {
-                    $file = substr_replace($file, $fmt[$i], 0, strlen($k));
+                    $file = substr_replace($file, $fmt[$i], 0, \strlen($k));
                     break;
                 }
             }
diff --git a/src/Symfony/Component/HttpKernel/DependencyInjection/AddAnnotatedClassesToCachePass.php b/src/Symfony/Component/HttpKernel/DependencyInjection/AddAnnotatedClassesToCachePass.php
index 8a86c69228..a9a97fd785 100644
--- a/src/Symfony/Component/HttpKernel/DependencyInjection/AddAnnotatedClassesToCachePass.php
+++ b/src/Symfony/Component/HttpKernel/DependencyInjection/AddAnnotatedClassesToCachePass.php
@@ -88,7 +88,7 @@ class AddAnnotatedClassesToCachePass implements CompilerPassInterface
         $classes = array();
 
         foreach (spl_autoload_functions() as $function) {
-            if (!is_array($function)) {
+            if (!\is_array($function)) {
                 continue;
             }
 
@@ -96,7 +96,7 @@ class AddAnnotatedClassesToCachePass implements CompilerPassInterface
                 $function = $function[0]->getClassLoader();
             }
 
-            if (is_array($function) && $function[0] instanceof ClassLoader) {
+            if (\is_array($function) && $function[0] instanceof ClassLoader) {
                 $classes += array_filter($function[0]->getClassMap());
             }
         }
diff --git a/src/Symfony/Component/HttpKernel/DependencyInjection/MergeExtensionConfigurationPass.php b/src/Symfony/Component/HttpKernel/DependencyInjection/MergeExtensionConfigurationPass.php
index dcd73828de..1dbf7f7bee 100644
--- a/src/Symfony/Component/HttpKernel/DependencyInjection/MergeExtensionConfigurationPass.php
+++ b/src/Symfony/Component/HttpKernel/DependencyInjection/MergeExtensionConfigurationPass.php
@@ -31,7 +31,7 @@ class MergeExtensionConfigurationPass extends BaseMergeExtensionConfigurationPas
     public function process(ContainerBuilder $container)
     {
         foreach ($this->extensions as $extension) {
-            if (!count($container->getExtensionConfig($extension))) {
+            if (!\count($container->getExtensionConfig($extension))) {
                 $container->loadFromExtension($extension, array());
             }
         }
diff --git a/src/Symfony/Component/HttpKernel/EventListener/DebugHandlersListener.php b/src/Symfony/Component/HttpKernel/EventListener/DebugHandlersListener.php
index 4c2398cc0d..e0088edb61 100644
--- a/src/Symfony/Component/HttpKernel/EventListener/DebugHandlersListener.php
+++ b/src/Symfony/Component/HttpKernel/EventListener/DebugHandlersListener.php
@@ -70,14 +70,14 @@ class DebugHandlersListener implements EventSubscriberInterface
         $this->firstCall = $this->hasTerminatedWithException = false;
 
         $handler = set_exception_handler('var_dump');
-        $handler = is_array($handler) ? $handler[0] : null;
+        $handler = \is_array($handler) ? $handler[0] : null;
         restore_exception_handler();
 
         if ($this->logger || null !== $this->throwAt) {
             if ($handler instanceof ErrorHandler) {
                 if ($this->logger) {
                     $handler->setDefaultLogger($this->logger, $this->levels);
-                    if (is_array($this->levels)) {
+                    if (\is_array($this->levels)) {
                         $levels = 0;
                         foreach ($this->levels as $type => $log) {
                             $levels |= $type;
@@ -126,7 +126,7 @@ class DebugHandlersListener implements EventSubscriberInterface
         if ($this->exceptionHandler) {
             if ($handler instanceof ErrorHandler) {
                 $h = $handler->setExceptionHandler('var_dump');
-                if (is_array($h) && $h[0] instanceof ExceptionHandler) {
+                if (\is_array($h) && $h[0] instanceof ExceptionHandler) {
                     $handler->setExceptionHandler($h);
                     $handler = $h[0];
                 } else {
@@ -147,7 +147,7 @@ class DebugHandlersListener implements EventSubscriberInterface
     {
         $events = array(KernelEvents::REQUEST => array('configure', 2048));
 
-        if ('cli' === PHP_SAPI && defined('Symfony\Component\Console\ConsoleEvents::COMMAND')) {
+        if ('cli' === PHP_SAPI && \defined('Symfony\Component\Console\ConsoleEvents::COMMAND')) {
             $events[ConsoleEvents::COMMAND] = array('configure', 2048);
         }
 
diff --git a/src/Symfony/Component/HttpKernel/EventListener/ExceptionListener.php b/src/Symfony/Component/HttpKernel/EventListener/ExceptionListener.php
index 4fc7e32fed..ee62b0131d 100644
--- a/src/Symfony/Component/HttpKernel/EventListener/ExceptionListener.php
+++ b/src/Symfony/Component/HttpKernel/EventListener/ExceptionListener.php
@@ -52,7 +52,7 @@ class ExceptionListener implements EventSubscriberInterface
     {
         $exception = $event->getException();
 
-        $this->logException($exception, sprintf('Uncaught PHP Exception %s: "%s" at %s line %s', get_class($exception), $exception->getMessage(), $exception->getFile(), $exception->getLine()));
+        $this->logException($exception, sprintf('Uncaught PHP Exception %s: "%s" at %s line %s', \get_class($exception), $exception->getMessage(), $exception->getFile(), $exception->getLine()));
     }
 
     public function onKernelException(GetResponseForExceptionEvent $event)
@@ -70,12 +70,12 @@ class ExceptionListener implements EventSubscriberInterface
         }
         $exception = $event->getException();
         $request = $this->duplicateRequest($exception, $event->getRequest());
-        $eventDispatcher = func_num_args() > 2 ? func_get_arg(2) : null;
+        $eventDispatcher = \func_num_args() > 2 ? func_get_arg(2) : null;
 
         try {
             $response = $event->getKernel()->handle($request, HttpKernelInterface::SUB_REQUEST, false);
         } catch (\Exception $e) {
-            $this->logException($e, sprintf('Exception thrown when handling an exception (%s: %s at %s line %s)', get_class($e), $e->getMessage(), $e->getFile(), $e->getLine()));
+            $this->logException($e, sprintf('Exception thrown when handling an exception (%s: %s at %s line %s)', \get_class($e), $e->getMessage(), $e->getFile(), $e->getLine()));
 
             $wrapper = $e;
 
diff --git a/src/Symfony/Component/HttpKernel/Exception/ControllerDoesNotReturnResponseException.php b/src/Symfony/Component/HttpKernel/Exception/ControllerDoesNotReturnResponseException.php
index 2abc4069cf..39149aa5b7 100644
--- a/src/Symfony/Component/HttpKernel/Exception/ControllerDoesNotReturnResponseException.php
+++ b/src/Symfony/Component/HttpKernel/Exception/ControllerDoesNotReturnResponseException.php
@@ -38,11 +38,11 @@ class ControllerDoesNotReturnResponseException extends \LogicException
 
     private function parseControllerDefinition(callable $controller): ?array
     {
-        if (is_string($controller) && false !== strpos($controller, '::')) {
+        if (\is_string($controller) && false !== strpos($controller, '::')) {
             $controller = explode('::', $controller);
         }
 
-        if (is_array($controller)) {
+        if (\is_array($controller)) {
             try {
                 $r = new \ReflectionMethod($controller[0], $controller[1]);
 
@@ -64,7 +64,7 @@ class ControllerDoesNotReturnResponseException extends \LogicException
             );
         }
 
-        if (is_object($controller)) {
+        if (\is_object($controller)) {
             $r = new \ReflectionClass($controller);
 
             return array(
diff --git a/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php b/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php
index ba1f368703..6ab6ec1fd0 100644
--- a/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php
+++ b/src/Symfony/Component/HttpKernel/Fragment/AbstractSurrogateFragmentRenderer.php
@@ -92,13 +92,13 @@ abstract class AbstractSurrogateFragmentRenderer extends RoutableFragmentRendere
         // we need to sign the absolute URI, but want to return the path only.
         $fragmentUri = $this->signer->sign($this->generateFragmentUri($uri, $request, true));
 
-        return substr($fragmentUri, strlen($request->getSchemeAndHttpHost()));
+        return substr($fragmentUri, \strlen($request->getSchemeAndHttpHost()));
     }
 
     private function containsNonScalars(array $values): bool
     {
         foreach ($values as $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 return $this->containsNonScalars($value);
             } elseif (!is_scalar($value) && null !== $value) {
                 return true;
diff --git a/src/Symfony/Component/HttpKernel/Fragment/HIncludeFragmentRenderer.php b/src/Symfony/Component/HttpKernel/Fragment/HIncludeFragmentRenderer.php
index d65d373ee3..714ffe5f8c 100644
--- a/src/Symfony/Component/HttpKernel/Fragment/HIncludeFragmentRenderer.php
+++ b/src/Symfony/Component/HttpKernel/Fragment/HIncludeFragmentRenderer.php
@@ -89,7 +89,7 @@ class HIncludeFragmentRenderer extends RoutableFragmentRenderer
             }
 
             // we need to sign the absolute URI, but want to return the path only.
-            $uri = substr($this->signer->sign($this->generateFragmentUri($uri, $request, true)), strlen($request->getSchemeAndHttpHost()));
+            $uri = substr($this->signer->sign($this->generateFragmentUri($uri, $request, true)), \strlen($request->getSchemeAndHttpHost()));
         }
 
         // We need to replace ampersands in the URI with the encoded form in order to return valid html/xml content.
@@ -102,12 +102,12 @@ class HIncludeFragmentRenderer extends RoutableFragmentRenderer
             $content = $template;
         }
 
-        $attributes = isset($options['attributes']) && is_array($options['attributes']) ? $options['attributes'] : array();
+        $attributes = isset($options['attributes']) && \is_array($options['attributes']) ? $options['attributes'] : array();
         if (isset($options['id']) && $options['id']) {
             $attributes['id'] = $options['id'];
         }
         $renderedAttributes = '';
-        if (count($attributes) > 0) {
+        if (\count($attributes) > 0) {
             $flags = ENT_QUOTES | ENT_SUBSTITUTE;
             foreach ($attributes as $attribute => $value) {
                 $renderedAttributes .= sprintf(
diff --git a/src/Symfony/Component/HttpKernel/Fragment/RoutableFragmentRenderer.php b/src/Symfony/Component/HttpKernel/Fragment/RoutableFragmentRenderer.php
index d7eeb89a6b..087995f290 100644
--- a/src/Symfony/Component/HttpKernel/Fragment/RoutableFragmentRenderer.php
+++ b/src/Symfony/Component/HttpKernel/Fragment/RoutableFragmentRenderer.php
@@ -80,7 +80,7 @@ abstract class RoutableFragmentRenderer implements FragmentRendererInterface
     private function checkNonScalar($values)
     {
         foreach ($values as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $this->checkNonScalar($value);
             } elseif (!is_scalar($value) && null !== $value) {
                 throw new \LogicException(sprintf('Controller attributes cannot contain non-scalar/non-null values (value for key "%s" is not a scalar or null).', $key));
diff --git a/src/Symfony/Component/HttpKernel/HttpCache/Esi.php b/src/Symfony/Component/HttpKernel/HttpCache/Esi.php
index d09907ea62..69134c71a1 100644
--- a/src/Symfony/Component/HttpKernel/HttpCache/Esi.php
+++ b/src/Symfony/Component/HttpKernel/HttpCache/Esi.php
@@ -71,7 +71,7 @@ class Esi extends AbstractSurrogate
         }
 
         $parts = explode(';', $type);
-        if (!in_array($parts[0], $this->contentTypes)) {
+        if (!\in_array($parts[0], $this->contentTypes)) {
             return $response;
         }
 
diff --git a/src/Symfony/Component/HttpKernel/HttpCache/HttpCache.php b/src/Symfony/Component/HttpKernel/HttpCache/HttpCache.php
index aa234f13ba..32c3556ef3 100644
--- a/src/Symfony/Component/HttpKernel/HttpCache/HttpCache.php
+++ b/src/Symfony/Component/HttpKernel/HttpCache/HttpCache.php
@@ -370,7 +370,7 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
 
             // return the response and not the cache entry if the response is valid but not cached
             $etag = $response->getEtag();
-            if ($etag && in_array($etag, $requestEtags) && !in_array($etag, $cachedEtags)) {
+            if ($etag && \in_array($etag, $requestEtags) && !\in_array($etag, $cachedEtags)) {
                 return $response;
             }
 
@@ -457,7 +457,7 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
         $request->server->set('REMOTE_ADDR', '127.0.0.1');
 
         // make sure HttpCache is a trusted proxy
-        if (!in_array('127.0.0.1', $trustedProxies = Request::getTrustedProxies())) {
+        if (!\in_array('127.0.0.1', $trustedProxies = Request::getTrustedProxies())) {
             $trustedProxies[] = '127.0.0.1';
             Request::setTrustedProxies($trustedProxies, Request::HEADER_X_FORWARDED_ALL);
         }
@@ -467,7 +467,7 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
         // FIXME: we probably need to also catch exceptions if raw === true
 
         // we don't implement the stale-if-error on Requests, which is nonetheless part of the RFC
-        if (null !== $entry && in_array($response->getStatusCode(), array(500, 502, 503, 504))) {
+        if (null !== $entry && \in_array($response->getStatusCode(), array(500, 502, 503, 504))) {
             if (null === $age = $entry->headers->getCacheControlDirective('stale-if-error')) {
                 $age = $this->options['stale_if_error'];
             }
@@ -606,7 +606,7 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
             $response->setContent(ob_get_clean());
             $response->headers->remove('X-Body-Eval');
             if (!$response->headers->has('Transfer-Encoding')) {
-                $response->headers->set('Content-Length', strlen($response->getContent()));
+                $response->headers->set('Content-Length', \strlen($response->getContent()));
             }
         } elseif ($response->headers->has('X-Body-File')) {
             // Response does not include possibly dynamic content (ESI, SSI), so we need
@@ -640,7 +640,7 @@ class HttpCache implements HttpKernelInterface, TerminableInterface
             $key = strtolower(str_replace('HTTP_', '', $key));
 
             if ('cookie' === $key) {
-                if (count($request->cookies->all())) {
+                if (\count($request->cookies->all())) {
                     return true;
                 }
             } elseif ($request->headers->has($key)) {
diff --git a/src/Symfony/Component/HttpKernel/HttpCache/Ssi.php b/src/Symfony/Component/HttpKernel/HttpCache/Ssi.php
index 3178c33515..58df176019 100644
--- a/src/Symfony/Component/HttpKernel/HttpCache/Ssi.php
+++ b/src/Symfony/Component/HttpKernel/HttpCache/Ssi.php
@@ -58,7 +58,7 @@ class Ssi extends AbstractSurrogate
         }
 
         $parts = explode(';', $type);
-        if (!in_array($parts[0], $this->contentTypes)) {
+        if (!\in_array($parts[0], $this->contentTypes)) {
             return $response;
         }
 
diff --git a/src/Symfony/Component/HttpKernel/HttpCache/Store.php b/src/Symfony/Component/HttpKernel/HttpCache/Store.php
index 5f54dbe62e..d4363185c7 100644
--- a/src/Symfony/Component/HttpKernel/HttpCache/Store.php
+++ b/src/Symfony/Component/HttpKernel/HttpCache/Store.php
@@ -66,7 +66,7 @@ class Store implements StoreInterface
 
         if (!isset($this->locks[$key])) {
             $path = $this->getPath($key);
-            if (!file_exists(dirname($path)) && false === @mkdir(dirname($path), 0777, true) && !is_dir(dirname($path))) {
+            if (!file_exists(\dirname($path)) && false === @mkdir(\dirname($path), 0777, true) && !is_dir(\dirname($path))) {
                 return $path;
             }
             $h = fopen($path, 'cb');
@@ -185,7 +185,7 @@ class Store implements StoreInterface
             $response->headers->set('X-Content-Digest', $digest);
 
             if (!$response->headers->has('Transfer-Encoding')) {
-                $response->headers->set('Content-Length', strlen($response->getContent()));
+                $response->headers->set('Content-Length', \strlen($response->getContent()));
             }
         }
 
@@ -373,17 +373,17 @@ class Store implements StoreInterface
             @ftruncate($fp, 0);
             @fseek($fp, 0);
             $len = @fwrite($fp, $data);
-            if (strlen($data) !== $len) {
+            if (\strlen($data) !== $len) {
                 @ftruncate($fp, 0);
 
                 return false;
             }
         } else {
-            if (!file_exists(dirname($path)) && false === @mkdir(dirname($path), 0777, true) && !is_dir(dirname($path))) {
+            if (!file_exists(\dirname($path)) && false === @mkdir(\dirname($path), 0777, true) && !is_dir(\dirname($path))) {
                 return false;
             }
 
-            $tmpFile = tempnam(dirname($path), basename($path));
+            $tmpFile = tempnam(\dirname($path), basename($path));
             if (false === $fp = @fopen($tmpFile, 'wb')) {
                 @unlink($tmpFile);
 
diff --git a/src/Symfony/Component/HttpKernel/HttpKernel.php b/src/Symfony/Component/HttpKernel/HttpKernel.php
index eee1ca9830..a4245e8fdb 100644
--- a/src/Symfony/Component/HttpKernel/HttpKernel.php
+++ b/src/Symfony/Component/HttpKernel/HttpKernel.php
@@ -252,11 +252,11 @@ class HttpKernel implements HttpKernelInterface, TerminableInterface
 
     private function varToString($var): string
     {
-        if (is_object($var)) {
-            return sprintf('an object of type %s', get_class($var));
+        if (\is_object($var)) {
+            return sprintf('an object of type %s', \get_class($var));
         }
 
-        if (is_array($var)) {
+        if (\is_array($var)) {
             $a = array();
             foreach ($var as $k => $v) {
                 $a[] = sprintf('%s => ...', $k);
@@ -265,7 +265,7 @@ class HttpKernel implements HttpKernelInterface, TerminableInterface
             return sprintf('an array ([%s])', mb_substr(implode(', ', $a), 0, 255));
         }
 
-        if (is_resource($var)) {
+        if (\is_resource($var)) {
             return sprintf('a resource (%s)', get_resource_type($var));
         }
 
@@ -281,7 +281,7 @@ class HttpKernel implements HttpKernelInterface, TerminableInterface
             return 'a boolean value (true)';
         }
 
-        if (is_string($var)) {
+        if (\is_string($var)) {
             return sprintf('a string ("%s%s")', mb_substr($var, 0, 255), mb_strlen($var) > 255 ? '...' : '');
         }
 
diff --git a/src/Symfony/Component/HttpKernel/Kernel.php b/src/Symfony/Component/HttpKernel/Kernel.php
index 89e481aa38..0fbb9cf5fb 100644
--- a/src/Symfony/Component/HttpKernel/Kernel.php
+++ b/src/Symfony/Component/HttpKernel/Kernel.php
@@ -215,7 +215,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
     public function getBundle($name)
     {
         if (!isset($this->bundles[$name])) {
-            throw new \InvalidArgumentException(sprintf('Bundle "%s" does not exist or it is not enabled. Maybe you forgot to add it in the registerBundles() method of your %s.php file?', $name, get_class($this)));
+            throw new \InvalidArgumentException(sprintf('Bundle "%s" does not exist or it is not enabled. Maybe you forgot to add it in the registerBundles() method of your %s.php file?', $name, \get_class($this)));
         }
 
         return $this->bundles[$name];
@@ -268,7 +268,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
             $resourceBundle = $bundle->getName();
         }
 
-        if (count($files) > 0) {
+        if (\count($files) > 0) {
             return $first && $isResource ? $files[0] : $files;
         }
 
@@ -313,7 +313,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
     {
         if (null === $this->rootDir) {
             $r = new \ReflectionObject($this);
-            $this->rootDir = dirname($r->getFileName());
+            $this->rootDir = \dirname($r->getFileName());
         }
 
         return $this->rootDir;
@@ -328,12 +328,12 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
     {
         if (null === $this->projectDir) {
             $r = new \ReflectionObject($this);
-            $dir = $rootDir = dirname($r->getFileName());
+            $dir = $rootDir = \dirname($r->getFileName());
             while (!file_exists($dir.'/composer.json')) {
-                if ($dir === dirname($dir)) {
+                if ($dir === \dirname($dir)) {
                     return $this->projectDir = $rootDir;
                 }
-                $dir = dirname($dir);
+                $dir = \dirname($dir);
             }
             $this->projectDir = $dir;
         }
@@ -481,7 +481,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
 
         if ($this->debug) {
             $collectedLogs = array();
-            $previousHandler = defined('PHPUNIT_COMPOSER_INSTALL');
+            $previousHandler = \defined('PHPUNIT_COMPOSER_INSTALL');
             $previousHandler = $previousHandler ?: set_error_handler(function ($type, $message, $file, $line) use (&$collectedLogs, &$previousHandler) {
                 if (E_USER_DEPRECATED !== $type && E_DEPRECATED !== $type) {
                     return $previousHandler ? $previousHandler($type, $message, $file, $line) : false;
@@ -497,7 +497,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
                 // Clean the trace by removing first frames added by the error handler itself.
                 for ($i = 0; isset($backtrace[$i]); ++$i) {
                     if (isset($backtrace[$i]['file'], $backtrace[$i]['line']) && $backtrace[$i]['line'] === $line && $backtrace[$i]['file'] === $file) {
-                        $backtrace = array_slice($backtrace, 1 + $i);
+                        $backtrace = \array_slice($backtrace, 1 + $i);
                         break;
                     }
                 }
@@ -536,20 +536,20 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
                 error_reporting($errorLevel);
             }
         }
-        $oldContainer = is_object($oldContainer) ? new \ReflectionClass($oldContainer) : false;
+        $oldContainer = \is_object($oldContainer) ? new \ReflectionClass($oldContainer) : false;
 
         $this->dumpContainer($cache, $container, $class, $this->getContainerBaseClass());
         $this->container = require $cache->getPath();
         $this->container->set('kernel', $this);
 
-        if ($oldContainer && get_class($this->container) !== $oldContainer->name) {
+        if ($oldContainer && \get_class($this->container) !== $oldContainer->name) {
             // Because concurrent requests might still be using them,
             // old container files are not removed immediately,
             // but on a next dump of the container.
             static $legacyContainers = array();
-            $oldContainerDir = dirname($oldContainer->getFileName());
+            $oldContainerDir = \dirname($oldContainer->getFileName());
             $legacyContainers[$oldContainerDir.'.legacy'] = true;
-            foreach (glob(dirname($oldContainerDir).DIRECTORY_SEPARATOR.'*.legacy') as $legacyContainer) {
+            foreach (glob(\dirname($oldContainerDir).DIRECTORY_SEPARATOR.'*.legacy') as $legacyContainer) {
                 if (!isset($legacyContainers[$legacyContainer]) && @unlink($legacyContainer)) {
                     (new Filesystem())->remove(substr($legacyContainer, 0, -7));
                 }
@@ -574,7 +574,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
         $bundlesMetadata = array();
 
         foreach ($this->bundles as $name => $bundle) {
-            $bundles[$name] = get_class($bundle);
+            $bundles[$name] = \get_class($bundle);
             $bundlesMetadata[$name] = array(
                 'path' => $bundle->getPath(),
                 'namespace' => $bundle->getNamespace(),
@@ -705,14 +705,14 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
         ));
 
         $rootCode = array_pop($content);
-        $dir = dirname($cache->getPath()).'/';
+        $dir = \dirname($cache->getPath()).'/';
         $fs = new Filesystem();
 
         foreach ($content as $file => $code) {
             $fs->dumpFile($dir.$file, $code);
             @chmod($dir.$file, 0666 & ~umask());
         }
-        @unlink(dirname($dir.$file).'.legacy');
+        @unlink(\dirname($dir.$file).'.legacy');
 
         $cache->write($rootCode, $container->getResources());
     }
@@ -750,7 +750,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
      */
     public static function stripComments($source)
     {
-        if (!function_exists('token_get_all')) {
+        if (!\function_exists('token_get_all')) {
             return $source;
         }
 
@@ -778,7 +778,7 @@ abstract class Kernel implements KernelInterface, RebootableInterface, Terminabl
 
                 // replace multiple new lines with a single newline
                 $rawChunk .= preg_replace(array('/\n{2,}/S'), "\n", $token[1]);
-            } elseif (in_array($token[0], array(T_COMMENT, T_DOC_COMMENT))) {
+            } elseif (\in_array($token[0], array(T_COMMENT, T_DOC_COMMENT))) {
                 $ignoreSpace = true;
             } else {
                 $rawChunk .= $token[1];
diff --git a/src/Symfony/Component/HttpKernel/Log/Logger.php b/src/Symfony/Component/HttpKernel/Log/Logger.php
index bf6ab49232..8b671d84df 100644
--- a/src/Symfony/Component/HttpKernel/Log/Logger.php
+++ b/src/Symfony/Component/HttpKernel/Log/Logger.php
@@ -58,7 +58,7 @@ class Logger extends AbstractLogger
 
         $this->minLevelIndex = self::$levels[$minLevel];
         $this->formatter = $formatter ?: array($this, 'format');
-        if (false === $this->handle = is_resource($output) ? $output : @fopen($output, 'a')) {
+        if (false === $this->handle = \is_resource($output) ? $output : @fopen($output, 'a')) {
             throw new InvalidArgumentException(sprintf('Unable to open "%s".', $output));
         }
     }
diff --git a/src/Symfony/Component/HttpKernel/Profiler/FileProfilerStorage.php b/src/Symfony/Component/HttpKernel/Profiler/FileProfilerStorage.php
index d7179e1264..955afed580 100644
--- a/src/Symfony/Component/HttpKernel/Profiler/FileProfilerStorage.php
+++ b/src/Symfony/Component/HttpKernel/Profiler/FileProfilerStorage.php
@@ -59,7 +59,7 @@ class FileProfilerStorage implements ProfilerStorageInterface
         fseek($file, 0, SEEK_END);
 
         $result = array();
-        while (count($result) < $limit && $line = $this->readLineFromFile($file)) {
+        while (\count($result) < $limit && $line = $this->readLineFromFile($file)) {
             $values = str_getcsv($line);
             list($csvToken, $csvIp, $csvMethod, $csvUrl, $csvTime, $csvParent, $csvStatusCode) = $values;
             $csvTime = (int) $csvTime;
@@ -134,7 +134,7 @@ class FileProfilerStorage implements ProfilerStorageInterface
         $profileIndexed = is_file($file);
         if (!$profileIndexed) {
             // Create directory
-            $dir = dirname($file);
+            $dir = \dirname($file);
             if (!is_dir($dir) && false === @mkdir($dir, 0777, true) && !is_dir($dir)) {
                 throw new \RuntimeException(sprintf('Unable to create the storage directory (%s).', $dir));
             }
diff --git a/src/Symfony/Component/HttpKernel/Profiler/Profiler.php b/src/Symfony/Component/HttpKernel/Profiler/Profiler.php
index 0216133b78..87983a8c81 100644
--- a/src/Symfony/Component/HttpKernel/Profiler/Profiler.php
+++ b/src/Symfony/Component/HttpKernel/Profiler/Profiler.php
@@ -101,7 +101,7 @@ class Profiler implements ResetInterface
         }
 
         if (!($ret = $this->storage->write($profile)) && null !== $this->logger) {
-            $this->logger->warning('Unable to store the profiler information.', array('configured_storage' => get_class($this->storage)));
+            $this->logger->warning('Unable to store the profiler information.', array('configured_storage' => \get_class($this->storage)));
         }
 
         return $ret;
diff --git a/src/Symfony/Component/HttpKernel/Tests/CacheWarmer/CacheWarmerTest.php b/src/Symfony/Component/HttpKernel/Tests/CacheWarmer/CacheWarmerTest.php
index 05666cb0dc..4d34e7bfc9 100644
--- a/src/Symfony/Component/HttpKernel/Tests/CacheWarmer/CacheWarmerTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/CacheWarmer/CacheWarmerTest.php
@@ -31,7 +31,7 @@ class CacheWarmerTest extends TestCase
     public function testWriteCacheFileCreatesTheFile()
     {
         $warmer = new TestCacheWarmer(self::$cacheFile);
-        $warmer->warmUp(dirname(self::$cacheFile));
+        $warmer->warmUp(\dirname(self::$cacheFile));
 
         $this->assertFileExists(self::$cacheFile);
     }
@@ -43,7 +43,7 @@ class CacheWarmerTest extends TestCase
     {
         $nonWritableFile = '/this/file/is/very/probably/not/writable';
         $warmer = new TestCacheWarmer($nonWritableFile);
-        $warmer->warmUp(dirname($nonWritableFile));
+        $warmer->warmUp(\dirname($nonWritableFile));
     }
 }
 
diff --git a/src/Symfony/Component/HttpKernel/Tests/ClientTest.php b/src/Symfony/Component/HttpKernel/Tests/ClientTest.php
index 08989fb00f..f044727079 100644
--- a/src/Symfony/Component/HttpKernel/Tests/ClientTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/ClientTest.php
@@ -119,7 +119,7 @@ class ClientTest extends TestCase
             $this->assertEquals(1, $file->getSize());
         }
 
-        $file->move(dirname($target), basename($target));
+        $file->move(\dirname($target), basename($target));
 
         $this->assertFileExists($target);
         unlink($target);
diff --git a/src/Symfony/Component/HttpKernel/Tests/DataCollector/ConfigDataCollectorTest.php b/src/Symfony/Component/HttpKernel/Tests/DataCollector/ConfigDataCollectorTest.php
index 4fb36afda2..09443588c2 100644
--- a/src/Symfony/Component/HttpKernel/Tests/DataCollector/ConfigDataCollectorTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/DataCollector/ConfigDataCollectorTest.php
@@ -38,9 +38,9 @@ class ConfigDataCollectorTest extends TestCase
         $this->assertSame(date_default_timezone_get(), $c->getPhpTimezone());
         $this->assertSame(Kernel::VERSION, $c->getSymfonyVersion());
         $this->assertNull($c->getToken());
-        $this->assertSame(extension_loaded('xdebug'), $c->hasXDebug());
-        $this->assertSame(extension_loaded('Zend OPcache') && ini_get('opcache.enable'), $c->hasZendOpcache());
-        $this->assertSame(extension_loaded('apcu') && ini_get('apc.enabled'), $c->hasApcu());
+        $this->assertSame(\extension_loaded('xdebug'), $c->hasXDebug());
+        $this->assertSame(\extension_loaded('Zend OPcache') && ini_get('opcache.enable'), $c->hasZendOpcache());
+        $this->assertSame(\extension_loaded('apcu') && ini_get('apc.enabled'), $c->hasApcu());
     }
 }
 
diff --git a/src/Symfony/Component/HttpKernel/Tests/EventListener/ExceptionListenerTest.php b/src/Symfony/Component/HttpKernel/Tests/EventListener/ExceptionListenerTest.php
index 32146f00c1..66a6e5eadb 100644
--- a/src/Symfony/Component/HttpKernel/Tests/EventListener/ExceptionListenerTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/EventListener/ExceptionListenerTest.php
@@ -37,9 +37,9 @@ class ExceptionListenerTest extends TestCase
         $logger = new TestLogger();
         $l = new ExceptionListener('foo', $logger);
 
-        $_logger = new \ReflectionProperty(get_class($l), 'logger');
+        $_logger = new \ReflectionProperty(\get_class($l), 'logger');
         $_logger->setAccessible(true);
-        $_controller = new \ReflectionProperty(get_class($l), 'controller');
+        $_controller = new \ReflectionProperty(\get_class($l), 'controller');
         $_controller->setAccessible(true);
 
         $this->assertSame($logger, $_logger->getValue($l));
@@ -180,7 +180,7 @@ class TestLogger extends Logger implements DebugLoggerInterface
 {
     public function countErrors()
     {
-        return count($this->logs['critical']);
+        return \count($this->logs['critical']);
     }
 }
 
diff --git a/src/Symfony/Component/HttpKernel/Tests/Fragment/FragmentHandlerTest.php b/src/Symfony/Component/HttpKernel/Tests/Fragment/FragmentHandlerTest.php
index 9c906b50a0..a625795fba 100644
--- a/src/Symfony/Component/HttpKernel/Tests/Fragment/FragmentHandlerTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/Fragment/FragmentHandlerTest.php
@@ -88,7 +88,7 @@ class FragmentHandlerTest extends TestCase
         ;
 
         if ($arguments) {
-            call_user_func_array(array($e, 'with'), $arguments);
+            \call_user_func_array(array($e, 'with'), $arguments);
         }
 
         $handler = new FragmentHandler($this->requestStack);
diff --git a/src/Symfony/Component/HttpKernel/Tests/HttpCache/EsiTest.php b/src/Symfony/Component/HttpKernel/Tests/HttpCache/EsiTest.php
index a8662b2a2b..dbf9508356 100644
--- a/src/Symfony/Component/HttpKernel/Tests/HttpCache/EsiTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/HttpCache/EsiTest.php
@@ -231,10 +231,10 @@ class EsiTest extends TestCase
               ->method('getRequest')
               ->will($this->returnValue($request))
         ;
-        if (is_array($response)) {
+        if (\is_array($response)) {
             $cache->expects($this->any())
                   ->method('handle')
-                  ->will(call_user_func_array(array($this, 'onConsecutiveCalls'), $response))
+                  ->will(\call_user_func_array(array($this, 'onConsecutiveCalls'), $response))
             ;
         } else {
             $cache->expects($this->any())
diff --git a/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTest.php b/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTest.php
index 0a77648003..8bc3bcb929 100644
--- a/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTest.php
@@ -215,7 +215,7 @@ class HttpCacheTest extends HttpCacheTestCase
             if ($request->cookies->has('authenticated')) {
                 $response->headers->set('Cache-Control', 'private, no-store');
                 $response->setETag('"private tag"');
-                if (in_array('"private tag"', $etags)) {
+                if (\in_array('"private tag"', $etags)) {
                     $response->setStatusCode(304);
                 } else {
                     $response->setStatusCode(200);
@@ -225,7 +225,7 @@ class HttpCacheTest extends HttpCacheTestCase
             } else {
                 $response->headers->set('Cache-Control', 'public');
                 $response->setETag('"public tag"');
-                if (in_array('"public tag"', $etags)) {
+                if (\in_array('"public tag"', $etags)) {
                     $response->setStatusCode(304);
                 } else {
                     $response->setStatusCode(200);
@@ -994,7 +994,7 @@ class HttpCacheTest extends HttpCacheTestCase
         $this->assertHttpKernelIsNotCalled();
         $this->assertEquals(200, $this->response->getStatusCode());
         $this->assertEquals('', $this->response->getContent());
-        $this->assertEquals(strlen('Hello World'), $this->response->headers->get('Content-Length'));
+        $this->assertEquals(\strlen('Hello World'), $this->response->headers->get('Content-Length'));
     }
 
     public function testSendsNoContentWhenFresh()
diff --git a/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTestCase.php b/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTestCase.php
index ed5c690d60..b3aa2be2f0 100644
--- a/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTestCase.php
+++ b/src/Symfony/Component/HttpKernel/Tests/HttpCache/HttpCacheTestCase.php
@@ -168,7 +168,7 @@ class HttpCacheTestCase extends TestCase
 
         $fp = opendir($directory);
         while (false !== $file = readdir($fp)) {
-            if (!in_array($file, array('.', '..'))) {
+            if (!\in_array($file, array('.', '..'))) {
                 if (is_link($directory.'/'.$file)) {
                     unlink($directory.'/'.$file);
                 } elseif (is_dir($directory.'/'.$file)) {
diff --git a/src/Symfony/Component/HttpKernel/Tests/HttpCache/SsiTest.php b/src/Symfony/Component/HttpKernel/Tests/HttpCache/SsiTest.php
index 1079d37a27..26ef6cb2b8 100644
--- a/src/Symfony/Component/HttpKernel/Tests/HttpCache/SsiTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/HttpCache/SsiTest.php
@@ -198,10 +198,10 @@ class SsiTest extends TestCase
               ->method('getRequest')
               ->will($this->returnValue($request))
         ;
-        if (is_array($response)) {
+        if (\is_array($response)) {
             $cache->expects($this->any())
                   ->method('handle')
-                  ->will(call_user_func_array(array($this, 'onConsecutiveCalls'), $response))
+                  ->will(\call_user_func_array(array($this, 'onConsecutiveCalls'), $response))
             ;
         } else {
             $cache->expects($this->any())
diff --git a/src/Symfony/Component/HttpKernel/Tests/HttpKernelTest.php b/src/Symfony/Component/HttpKernel/Tests/HttpKernelTest.php
index d7c61a1ea9..a7064ef6b9 100644
--- a/src/Symfony/Component/HttpKernel/Tests/HttpKernelTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/HttpKernelTest.php
@@ -274,7 +274,7 @@ class HttpKernelTest extends TestCase
             $oldArguments = $event->getArguments();
 
             $newController = function ($id) use ($oldController, $oldArguments) {
-                $response = call_user_func_array($oldController, $oldArguments);
+                $response = \call_user_func_array($oldController, $oldArguments);
 
                 $response->headers->set('X-Id', $id);
 
diff --git a/src/Symfony/Component/HttpKernel/Tests/KernelTest.php b/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
index 5a302d3090..97321f05b8 100644
--- a/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
+++ b/src/Symfony/Component/HttpKernel/Tests/KernelTest.php
@@ -74,7 +74,7 @@ class KernelTest extends TestCase
         $kernel = new CustomProjectDirKernel();
         $kernel->boot();
 
-        $containerDir = __DIR__.'/Fixtures/cache/custom/'.substr(get_class($kernel->getContainer()), 0, 16);
+        $containerDir = __DIR__.'/Fixtures/cache/custom/'.substr(\get_class($kernel->getContainer()), 0, 16);
         $this->assertTrue(unlink(__DIR__.'/Fixtures/cache/custom/FixturesCustomDebugProjectContainer.php.meta'));
         $this->assertFileExists($containerDir);
         $this->assertFileNotExists($containerDir.'.legacy');
@@ -530,7 +530,7 @@ EOF;
         $kernel = new CustomProjectDirKernel();
         $kernel->boot();
 
-        $containerClass = get_class($kernel->getContainer());
+        $containerClass = \get_class($kernel->getContainer());
         $containerFile = (new \ReflectionClass($kernel->getContainer()))->getFileName();
         unlink(__DIR__.'/Fixtures/cache/custom/FixturesCustomDebugProjectContainer.php.meta');
 
@@ -546,7 +546,7 @@ EOF;
 
         $this->assertNotInstanceOf($containerClass, $kernel->getContainer());
         $this->assertFileExists($containerFile);
-        $this->assertFileExists(dirname($containerFile).'.legacy');
+        $this->assertFileExists(\dirname($containerFile).'.legacy');
     }
 
     public function testKernelPass()
@@ -626,7 +626,7 @@ EOF;
         $bundle
             ->expects($this->any())
             ->method('getName')
-            ->will($this->returnValue(null === $bundleName ? get_class($bundle) : $bundleName))
+            ->will($this->returnValue(null === $bundleName ? \get_class($bundle) : $bundleName))
         ;
 
         $bundle
diff --git a/src/Symfony/Component/Inflector/Inflector.php b/src/Symfony/Component/Inflector/Inflector.php
index cf685159a7..b670b22dcd 100644
--- a/src/Symfony/Component/Inflector/Inflector.php
+++ b/src/Symfony/Component/Inflector/Inflector.php
@@ -163,7 +163,7 @@ final class Inflector
     {
         $pluralRev = strrev($plural);
         $lowerPluralRev = strtolower($pluralRev);
-        $pluralLength = strlen($lowerPluralRev);
+        $pluralLength = \strlen($lowerPluralRev);
 
         // The outer loop iterates over the entries of the plural table
         // The inner loop $j iterates over the characters of the plural suffix
@@ -206,7 +206,7 @@ final class Inflector
                     // the singular suffix too
                     $firstUpper = ctype_upper($pluralRev[$j - 1]);
 
-                    if (is_array($newSuffix)) {
+                    if (\is_array($newSuffix)) {
                         $singulars = array();
 
                         foreach ($newSuffix as $newSuffixEntry) {
diff --git a/src/Symfony/Component/Inflector/Tests/InflectorTest.php b/src/Symfony/Component/Inflector/Tests/InflectorTest.php
index be7836736f..8c40532a26 100644
--- a/src/Symfony/Component/Inflector/Tests/InflectorTest.php
+++ b/src/Symfony/Component/Inflector/Tests/InflectorTest.php
@@ -161,9 +161,9 @@ class InflectorTest extends TestCase
     public function testSingularize($plural, $singular)
     {
         $single = Inflector::singularize($plural);
-        if (is_string($singular) && is_array($single)) {
+        if (\is_string($singular) && \is_array($single)) {
             $this->fail("--- Expected\n`string`: ".$singular."\n+++ Actual\n`array`: ".implode(', ', $single));
-        } elseif (is_array($singular) && is_string($single)) {
+        } elseif (\is_array($singular) && \is_string($single)) {
             $this->fail("--- Expected\n`array`: ".implode(', ', $singular)."\n+++ Actual\n`string`: ".$single);
         }
 
diff --git a/src/Symfony/Component/Intl/Data/Bundle/Reader/BundleEntryReader.php b/src/Symfony/Component/Intl/Data/Bundle/Reader/BundleEntryReader.php
index aedcac9185..79f14c4b14 100644
--- a/src/Symfony/Component/Intl/Data/Bundle/Reader/BundleEntryReader.php
+++ b/src/Symfony/Component/Intl/Data/Bundle/Reader/BundleEntryReader.php
@@ -90,7 +90,7 @@ class BundleEntryReader implements BundleEntryReaderInterface
                 $readSucceeded = true;
 
                 $isCurrentTraversable = $currentEntry instanceof \Traversable;
-                $isCurrentMultiValued = $isCurrentTraversable || is_array($currentEntry);
+                $isCurrentMultiValued = $isCurrentTraversable || \is_array($currentEntry);
 
                 // Return immediately if fallback is disabled or we are dealing
                 // with a scalar non-null entry
@@ -162,7 +162,7 @@ class BundleEntryReader implements BundleEntryReaderInterface
         );
 
         // Append fallback locales, if any
-        if (count($testedLocales) > 1) {
+        if (\count($testedLocales) > 1) {
             // Remove original locale
             array_shift($testedLocales);
 
diff --git a/src/Symfony/Component/Intl/Data/Bundle/Reader/JsonBundleReader.php b/src/Symfony/Component/Intl/Data/Bundle/Reader/JsonBundleReader.php
index 17a9df32c2..b5786d12a2 100644
--- a/src/Symfony/Component/Intl/Data/Bundle/Reader/JsonBundleReader.php
+++ b/src/Symfony/Component/Intl/Data/Bundle/Reader/JsonBundleReader.php
@@ -31,7 +31,7 @@ class JsonBundleReader implements BundleReaderInterface
         $fileName = $path.'/'.$locale.'.json';
 
         // prevent directory traversal attacks
-        if (dirname($fileName) !== $path) {
+        if (\dirname($fileName) !== $path) {
             throw new ResourceBundleNotFoundException(sprintf('The resource bundle "%s" does not exist.', $fileName));
         }
 
diff --git a/src/Symfony/Component/Intl/Data/Bundle/Reader/PhpBundleReader.php b/src/Symfony/Component/Intl/Data/Bundle/Reader/PhpBundleReader.php
index 0b66bb1a55..7c4b71c93a 100644
--- a/src/Symfony/Component/Intl/Data/Bundle/Reader/PhpBundleReader.php
+++ b/src/Symfony/Component/Intl/Data/Bundle/Reader/PhpBundleReader.php
@@ -31,7 +31,7 @@ class PhpBundleReader implements BundleReaderInterface
         $fileName = $path.'/'.$locale.'.php';
 
         // prevent directory traversal attacks
-        if (dirname($fileName) !== $path) {
+        if (\dirname($fileName) !== $path) {
             throw new ResourceBundleNotFoundException(sprintf('The resource bundle "%s" does not exist.', $fileName));
         }
 
diff --git a/src/Symfony/Component/Intl/Data/Bundle/Writer/TextBundleWriter.php b/src/Symfony/Component/Intl/Data/Bundle/Writer/TextBundleWriter.php
index 20fad5347a..309e4303b1 100644
--- a/src/Symfony/Component/Intl/Data/Bundle/Writer/TextBundleWriter.php
+++ b/src/Symfony/Component/Intl/Data/Bundle/Writer/TextBundleWriter.php
@@ -72,7 +72,7 @@ class TextBundleWriter implements BundleWriterInterface
      */
     private function writeResource($file, $value, $indentation, $requireBraces = true)
     {
-        if (is_int($value)) {
+        if (\is_int($value)) {
             $this->writeInteger($file, $value);
 
             return;
@@ -82,13 +82,13 @@ class TextBundleWriter implements BundleWriterInterface
             $value = iterator_to_array($value);
         }
 
-        if (is_array($value)) {
-            $intValues = count($value) === count(array_filter($value, 'is_int'));
+        if (\is_array($value)) {
+            $intValues = \count($value) === \count(array_filter($value, 'is_int'));
 
             $keys = array_keys($value);
 
             // check that the keys are 0-indexed and ascending
-            $intKeys = $keys === range(0, count($keys) - 1);
+            $intKeys = $keys === range(0, \count($keys) - 1);
 
             if ($intValues && $intKeys) {
                 $this->writeIntVector($file, $value, $indentation);
@@ -107,7 +107,7 @@ class TextBundleWriter implements BundleWriterInterface
             return;
         }
 
-        if (is_bool($value)) {
+        if (\is_bool($value)) {
             $value = $value ? 'true' : 'false';
         }
 
@@ -206,7 +206,7 @@ class TextBundleWriter implements BundleWriterInterface
      */
     private function writeTable($file, $value, $indentation, $fallback = true)
     {
-        if (!is_array($value) && !$value instanceof \Traversable) {
+        if (!\is_array($value) && !$value instanceof \Traversable) {
             throw new UnexpectedTypeException($value, 'array or \Traversable');
         }
 
diff --git a/src/Symfony/Component/Intl/Data/Generator/LanguageDataGenerator.php b/src/Symfony/Component/Intl/Data/Generator/LanguageDataGenerator.php
index 565a872619..2640bb13de 100644
--- a/src/Symfony/Component/Intl/Data/Generator/LanguageDataGenerator.php
+++ b/src/Symfony/Component/Intl/Data/Generator/LanguageDataGenerator.php
@@ -169,7 +169,7 @@ class LanguageDataGenerator extends AbstractDataGenerator
 
         foreach ($aliases as $alias => $language) {
             $language = $language['replacement'];
-            if (2 === strlen($language) && 3 === strlen($alias)) {
+            if (2 === \strlen($language) && 3 === \strlen($alias)) {
                 if (isset(self::$preferredAlpha2ToAlpha3Mapping[$language])) {
                     // Validate to prevent typos
                     if (!isset($aliases[self::$preferredAlpha2ToAlpha3Mapping[$language]])) {
diff --git a/src/Symfony/Component/Intl/Data/Generator/LocaleDataGenerator.php b/src/Symfony/Component/Intl/Data/Generator/LocaleDataGenerator.php
index c89ac337c4..01f0f742ea 100644
--- a/src/Symfony/Component/Intl/Data/Generator/LocaleDataGenerator.php
+++ b/src/Symfony/Component/Intl/Data/Generator/LocaleDataGenerator.php
@@ -106,7 +106,7 @@ class LocaleDataGenerator
             }
 
             // If no names remain to be saved for the current locale, skip it
-            if (0 === count($localeNames[$displayLocale])) {
+            if (0 === \count($localeNames[$displayLocale])) {
                 continue;
             }
 
@@ -147,7 +147,7 @@ class LocaleDataGenerator
 
         // Currently the only available variant is POSIX, which we don't want
         // to include in the list
-        if (count($variants) > 0) {
+        if (\count($variants) > 0) {
             return;
         }
 
@@ -192,7 +192,7 @@ class LocaleDataGenerator
             $extras[] = $regionName;
         }
 
-        if (count($extras) > 0) {
+        if (\count($extras) > 0) {
             // Remove any existing extras
             // For example, in German, zh_Hans is "Chinesisch (vereinfacht)".
             // The latter is the script part which is already included in the
@@ -219,7 +219,7 @@ class LocaleDataGenerator
             while (null !== ($fallback = Locale::getFallback($fallback))) {
                 // Currently, no locale has an alias as fallback locale.
                 // If this starts to be the case, we need to add code here.
-                assert(!isset($aliases[$fallback]));
+                \assert(!isset($aliases[$fallback]));
 
                 // Check whether the fallback exists
                 if (isset($displayLocales[$fallback])) {
diff --git a/src/Symfony/Component/Intl/Data/Generator/RegionDataGenerator.php b/src/Symfony/Component/Intl/Data/Generator/RegionDataGenerator.php
index 7ae31bd121..b7204365fb 100644
--- a/src/Symfony/Component/Intl/Data/Generator/RegionDataGenerator.php
+++ b/src/Symfony/Component/Intl/Data/Generator/RegionDataGenerator.php
@@ -140,7 +140,7 @@ class RegionDataGenerator extends AbstractDataGenerator
             }
 
             // WORLD/CONTINENT/SUBCONTINENT/GROUPING
-            if (ctype_digit($region) || is_int($region)) {
+            if (ctype_digit($region) || \is_int($region)) {
                 continue;
             }
 
diff --git a/src/Symfony/Component/Intl/Data/Util/RecursiveArrayAccess.php b/src/Symfony/Component/Intl/Data/Util/RecursiveArrayAccess.php
index ff4d2f777c..086b550478 100644
--- a/src/Symfony/Component/Intl/Data/Util/RecursiveArrayAccess.php
+++ b/src/Symfony/Component/Intl/Data/Util/RecursiveArrayAccess.php
@@ -24,7 +24,7 @@ class RecursiveArrayAccess
     {
         foreach ($indices as $index) {
             // Use array_key_exists() for arrays, isset() otherwise
-            if (is_array($array)) {
+            if (\is_array($array)) {
                 if (array_key_exists($index, $array)) {
                     $array = $array[$index];
                     continue;
diff --git a/src/Symfony/Component/Intl/DateFormatter/DateFormat/FullTransformer.php b/src/Symfony/Component/Intl/DateFormatter/DateFormat/FullTransformer.php
index c66699a95e..a58d94e211 100644
--- a/src/Symfony/Component/Intl/DateFormatter/DateFormat/FullTransformer.php
+++ b/src/Symfony/Component/Intl/DateFormatter/DateFormat/FullTransformer.php
@@ -107,7 +107,7 @@ class FullTransformer
      */
     public function formatReplace($dateChars, $dateTime)
     {
-        $length = strlen($dateChars);
+        $length = \strlen($dateChars);
 
         if ($this->isQuoteMatch($dateChars)) {
             return $this->replaceQuoteMatch($dateChars);
@@ -147,7 +147,7 @@ class FullTransformer
 
             foreach ($this->transformers as $char => $transformer) {
                 if (isset($matches[$char])) {
-                    $length = strlen($matches[$char]['pattern']);
+                    $length = \strlen($matches[$char]['pattern']);
                     $options = array_merge($options, $transformer->extractDateOptions($matches[$char]['value'], $length));
                 }
             }
@@ -181,7 +181,7 @@ class FullTransformer
         $escapedPattern = preg_replace('/\\\[\-|\/]/', '[\/\-]', $escapedPattern);
 
         $reverseMatchingRegExp = preg_replace_callback($this->regExp, function ($matches) {
-            $length = strlen($matches[0]);
+            $length = \strlen($matches[0]);
             $transformerIndex = $matches[0][0];
 
             $dateChars = $matches[0];
@@ -258,7 +258,7 @@ class FullTransformer
         $ret = array();
 
         foreach ($data as $key => $value) {
-            if (!is_string($key)) {
+            if (!\is_string($key)) {
                 continue;
             }
 
@@ -313,7 +313,7 @@ class FullTransformer
 
         // Normalize yy year
         preg_match_all($this->regExp, $this->pattern, $matches);
-        if (in_array('yy', $matches[0])) {
+        if (\in_array('yy', $matches[0])) {
             $dateTime->setTimestamp(time());
             $year = $year > $dateTime->format('y') + 20 ? 1900 + $year : 2000 + $year;
         }
diff --git a/src/Symfony/Component/Intl/DateFormatter/DateFormat/MonthTransformer.php b/src/Symfony/Component/Intl/DateFormatter/DateFormat/MonthTransformer.php
index ed669398f0..b3c2862690 100644
--- a/src/Symfony/Component/Intl/DateFormatter/DateFormat/MonthTransformer.php
+++ b/src/Symfony/Component/Intl/DateFormatter/DateFormat/MonthTransformer.php
@@ -52,7 +52,7 @@ class MonthTransformer extends Transformer
 
     public function __construct()
     {
-        if (0 === count(self::$shortMonths)) {
+        if (0 === \count(self::$shortMonths)) {
             self::$shortMonths = array_map(function ($month) {
                 return substr($month, 0, 3);
             }, self::$months);
diff --git a/src/Symfony/Component/Intl/DateFormatter/DateFormat/TimezoneTransformer.php b/src/Symfony/Component/Intl/DateFormatter/DateFormat/TimezoneTransformer.php
index 77a6e86025..23734ed8fd 100644
--- a/src/Symfony/Component/Intl/DateFormatter/DateFormat/TimezoneTransformer.php
+++ b/src/Symfony/Component/Intl/DateFormatter/DateFormat/TimezoneTransformer.php
@@ -31,7 +31,7 @@ class TimezoneTransformer extends Transformer
     {
         $timeZone = substr($dateTime->getTimezone()->getName(), 0, 3);
 
-        if (!in_array($timeZone, array('Etc', 'UTC', 'GMT'))) {
+        if (!\in_array($timeZone, array('Etc', 'UTC', 'GMT'))) {
             throw new NotImplementedException('Time zone different than GMT or UTC is not supported as a formatting output.');
         }
 
@@ -41,7 +41,7 @@ class TimezoneTransformer extends Transformer
         }
 
         // From ICU >= 59.1 GMT and UTC are no longer unified
-        if (in_array($timeZone, array('UTC', 'UCT', 'Universal', 'Zulu'))) {
+        if (\in_array($timeZone, array('UTC', 'UCT', 'Universal', 'Zulu'))) {
             // offset is not supported with UTC
             return $length > 3 ? 'Coordinated Universal Time' : 'UTC';
         }
diff --git a/src/Symfony/Component/Intl/DateFormatter/IntlDateFormatter.php b/src/Symfony/Component/Intl/DateFormatter/IntlDateFormatter.php
index 90db708294..3b49368d95 100644
--- a/src/Symfony/Component/Intl/DateFormatter/IntlDateFormatter.php
+++ b/src/Symfony/Component/Intl/DateFormatter/IntlDateFormatter.php
@@ -187,7 +187,7 @@ class IntlDateFormatter
     public function format($timestamp)
     {
         // intl allows timestamps to be passed as arrays - we don't
-        if (is_array($timestamp)) {
+        if (\is_array($timestamp)) {
             $message = 'Only integer Unix timestamps and DateTime objects are supported';
 
             throw new MethodArgumentValueNotImplementedException(__METHOD__, 'timestamp', $timestamp, $message);
@@ -195,7 +195,7 @@ class IntlDateFormatter
 
         // behave like the intl extension
         $argumentError = null;
-        if (!is_int($timestamp) && !$timestamp instanceof \DateTime) {
+        if (!\is_int($timestamp) && !$timestamp instanceof \DateTime) {
             $argumentError = sprintf('datefmt_format: string \'%s\' is not numeric, which would be required for it to be a valid date', $timestamp);
         }
 
diff --git a/src/Symfony/Component/Intl/Exception/UnexpectedTypeException.php b/src/Symfony/Component/Intl/Exception/UnexpectedTypeException.php
index 739152346c..9ec42753e0 100644
--- a/src/Symfony/Component/Intl/Exception/UnexpectedTypeException.php
+++ b/src/Symfony/Component/Intl/Exception/UnexpectedTypeException.php
@@ -20,6 +20,6 @@ class UnexpectedTypeException extends InvalidArgumentException
 {
     public function __construct($value, string $expectedType)
     {
-        parent::__construct(sprintf('Expected argument of type "%s", "%s" given', $expectedType, is_object($value) ? get_class($value) : gettype($value)));
+        parent::__construct(sprintf('Expected argument of type "%s", "%s" given', $expectedType, \is_object($value) ? \get_class($value) : \gettype($value)));
     }
 }
diff --git a/src/Symfony/Component/Intl/Intl.php b/src/Symfony/Component/Intl/Intl.php
index b621d7e51d..55c4099035 100644
--- a/src/Symfony/Component/Intl/Intl.php
+++ b/src/Symfony/Component/Intl/Intl.php
@@ -194,7 +194,7 @@ final class Intl
         if (false === self::$icuVersion) {
             if (!self::isExtensionLoaded()) {
                 self::$icuVersion = self::getIcuStubVersion();
-            } elseif (defined('INTL_ICU_VERSION')) {
+            } elseif (\defined('INTL_ICU_VERSION')) {
                 self::$icuVersion = INTL_ICU_VERSION;
             } else {
                 try {
diff --git a/src/Symfony/Component/Intl/Locale.php b/src/Symfony/Component/Intl/Locale.php
index 9b74fa4da3..931400d4a4 100644
--- a/src/Symfony/Component/Intl/Locale.php
+++ b/src/Symfony/Component/Intl/Locale.php
@@ -67,16 +67,16 @@ final class Locale extends \Locale
      */
     public static function getFallback($locale): ?string
     {
-        if (function_exists('locale_parse')) {
+        if (\function_exists('locale_parse')) {
             $localeSubTags = locale_parse($locale);
-            if (1 === count($localeSubTags)) {
+            if (1 === \count($localeSubTags)) {
                 if (self::$defaultFallback === $localeSubTags['language']) {
                     return 'root';
                 }
 
                 // Don't return default fallback for "root", "meta" or others
                 // Normal locales have two or three letters
-                if (strlen($locale) < 4) {
+                if (\strlen($locale) < 4) {
                     return self::$defaultFallback;
                 }
 
@@ -102,7 +102,7 @@ final class Locale extends \Locale
 
         // Don't return default fallback for "root", "meta" or others
         // Normal locales have two or three letters
-        if (strlen($locale) < 4) {
+        if (\strlen($locale) < 4) {
             return self::$defaultFallback;
         }
 
diff --git a/src/Symfony/Component/Intl/NumberFormatter/NumberFormatter.php b/src/Symfony/Component/Intl/NumberFormatter/NumberFormatter.php
index 6503e09bfc..82f7342364 100644
--- a/src/Symfony/Component/Intl/NumberFormatter/NumberFormatter.php
+++ b/src/Symfony/Component/Intl/NumberFormatter/NumberFormatter.php
@@ -263,7 +263,7 @@ class NumberFormatter
             throw new MethodArgumentValueNotImplementedException(__METHOD__, 'locale', $locale, 'Only the locale "en" is supported');
         }
 
-        if (!in_array($style, self::$supportedStyles)) {
+        if (!\in_array($style, self::$supportedStyles)) {
             $message = sprintf('The available styles are: %s.', implode(', ', array_keys(self::$supportedStyles)));
             throw new MethodArgumentValueNotImplementedException(__METHOD__, 'style', $style, $message);
         }
@@ -521,9 +521,9 @@ class NumberFormatter
         // Any string before the numeric value causes error in the parsing
         if (preg_match("/^-?(?:\.\d++|([\d{$groupSep}]++)(?:\.\d++)?)/", $value, $matches)) {
             $value = $matches[0];
-            $position = strlen($value);
+            $position = \strlen($value);
             if ($error = $groupSep && isset($matches[1]) && !preg_match('/^\d{1,3}+(?:(?:,\d{3})++|\d*+)$/', $matches[1])) {
-                $position -= strlen(preg_replace('/^\d{1,3}+(?:(?:,\d++)++|\d*+)/', '', $matches[1]));
+                $position -= \strlen(preg_replace('/^\d{1,3}+(?:(?:,\d++)++|\d*+)/', '', $matches[1]));
             }
         } else {
             $error = 1;
@@ -564,7 +564,7 @@ class NumberFormatter
      */
     public function setAttribute($attr, $value)
     {
-        if (!in_array($attr, self::$supportedAttributes)) {
+        if (!\in_array($attr, self::$supportedAttributes)) {
             $message = sprintf(
                 'The available attributes are: %s',
                 implode(', ', array_keys(self::$supportedAttributes))
@@ -765,7 +765,7 @@ class NumberFormatter
         if (!$this->isInitializedAttribute(self::FRACTION_DIGITS)) {
             preg_match('/.*\.(.*)/', (string) $value, $digits);
             if (isset($digits[1])) {
-                $precision = strlen($digits[1]);
+                $precision = \strlen($digits[1]);
             }
         }
 
@@ -850,7 +850,7 @@ class NumberFormatter
      */
     private function isInvalidRoundingMode($value)
     {
-        if (in_array($value, self::$roundingModes, true)) {
+        if (\in_array($value, self::$roundingModes, true)) {
             return false;
         }
 
diff --git a/src/Symfony/Component/Intl/Tests/Data/Bundle/Reader/BundleEntryReaderTest.php b/src/Symfony/Component/Intl/Tests/Data/Bundle/Reader/BundleEntryReaderTest.php
index d76e2ab39a..3c483102c0 100644
--- a/src/Symfony/Component/Intl/Tests/Data/Bundle/Reader/BundleEntryReaderTest.php
+++ b/src/Symfony/Component/Intl/Tests/Data/Bundle/Reader/BundleEntryReaderTest.php
@@ -189,7 +189,7 @@ class BundleEntryReaderTest extends TestCase
      */
     public function testMergeDataWithFallbackData($childData, $parentData, $result)
     {
-        if (null === $childData || is_array($childData)) {
+        if (null === $childData || \is_array($childData)) {
             $this->readerImpl->expects($this->at(0))
                 ->method('read')
                 ->with(self::RES_DIR, 'en')
@@ -227,7 +227,7 @@ class BundleEntryReaderTest extends TestCase
      */
     public function testMergeExistingEntryWithExistingFallbackEntry($childData, $parentData, $result)
     {
-        if (null === $childData || is_array($childData)) {
+        if (null === $childData || \is_array($childData)) {
             $this->readerImpl->expects($this->at(0))
                 ->method('read')
                 ->with(self::RES_DIR, 'en')
@@ -270,7 +270,7 @@ class BundleEntryReaderTest extends TestCase
      */
     public function testMergeExistingEntryWithNonExistingFallbackEntry($childData, $parentData, $result)
     {
-        if (null === $childData || is_array($childData)) {
+        if (null === $childData || \is_array($childData)) {
             $this->readerImpl->expects($this->at(0))
                 ->method('read')
                 ->with(self::RES_DIR, 'en_GB')
@@ -313,8 +313,8 @@ class BundleEntryReaderTest extends TestCase
      */
     public function testMergeTraversables($childData, $parentData, $result)
     {
-        $parentData = is_array($parentData) ? new \ArrayObject($parentData) : $parentData;
-        $childData = is_array($childData) ? new \ArrayObject($childData) : $childData;
+        $parentData = \is_array($parentData) ? new \ArrayObject($parentData) : $parentData;
+        $childData = \is_array($childData) ? new \ArrayObject($childData) : $childData;
 
         if (null === $childData || $childData instanceof \ArrayObject) {
             $this->readerImpl->expects($this->at(0))
@@ -343,7 +343,7 @@ class BundleEntryReaderTest extends TestCase
     {
         $this->reader->setLocaleAliases(array('mo' => 'ro_MD'));
 
-        if (null === $childData || is_array($childData)) {
+        if (null === $childData || \is_array($childData)) {
             $this->readerImpl->expects($this->at(0))
                 ->method('read')
                 ->with(self::RES_DIR, 'ro_MD')
diff --git a/src/Symfony/Component/Intl/Tests/DateFormatter/AbstractIntlDateFormatterTest.php b/src/Symfony/Component/Intl/Tests/DateFormatter/AbstractIntlDateFormatterTest.php
index 7a4f01b66a..37342ae6e9 100644
--- a/src/Symfony/Component/Intl/Tests/DateFormatter/AbstractIntlDateFormatterTest.php
+++ b/src/Symfony/Component/Intl/Tests/DateFormatter/AbstractIntlDateFormatterTest.php
@@ -432,7 +432,7 @@ abstract class AbstractIntlDateFormatterTest extends TestCase
 
     public function testFormatWithIntlTimeZone()
     {
-        if (!extension_loaded('intl')) {
+        if (!\extension_loaded('intl')) {
             $this->markTestSkipped('Extension intl is required.');
         }
 
diff --git a/src/Symfony/Component/Intl/Tests/Locale/LocaleTest.php b/src/Symfony/Component/Intl/Tests/Locale/LocaleTest.php
index b0388620ba..63a943068c 100644
--- a/src/Symfony/Component/Intl/Tests/Locale/LocaleTest.php
+++ b/src/Symfony/Component/Intl/Tests/Locale/LocaleTest.php
@@ -170,8 +170,8 @@ class LocaleTest extends AbstractLocaleTest
 
     protected function call($methodName)
     {
-        $args = array_slice(func_get_args(), 1);
+        $args = \array_slice(\func_get_args(), 1);
 
-        return call_user_func_array(array('Symfony\Component\Intl\Locale\Locale', $methodName), $args);
+        return \call_user_func_array(array('Symfony\Component\Intl\Locale\Locale', $methodName), $args);
     }
 }
diff --git a/src/Symfony/Component/Intl/Tests/Locale/Verification/LocaleTest.php b/src/Symfony/Component/Intl/Tests/Locale/Verification/LocaleTest.php
index adfec280a7..cdcc0fdeb6 100644
--- a/src/Symfony/Component/Intl/Tests/Locale/Verification/LocaleTest.php
+++ b/src/Symfony/Component/Intl/Tests/Locale/Verification/LocaleTest.php
@@ -31,8 +31,8 @@ class LocaleTest extends AbstractLocaleTest
 
     protected function call($methodName)
     {
-        $args = array_slice(func_get_args(), 1);
+        $args = \array_slice(\func_get_args(), 1);
 
-        return call_user_func_array(array('Locale', $methodName), $args);
+        return \call_user_func_array(array('Locale', $methodName), $args);
     }
 }
diff --git a/src/Symfony/Component/Intl/Tests/LocaleTest.php b/src/Symfony/Component/Intl/Tests/LocaleTest.php
index e10df5575a..57059af9ae 100644
--- a/src/Symfony/Component/Intl/Tests/LocaleTest.php
+++ b/src/Symfony/Component/Intl/Tests/LocaleTest.php
@@ -28,7 +28,7 @@ class LocaleTest extends TestCase
             array(null, 'root'),
         );
 
-        if (function_exists('locale_parse')) {
+        if (\function_exists('locale_parse')) {
             $tests[] = array('sl_Latn_IT', 'sl-Latn-IT-nedis');
             $tests[] = array('sl_Latn', 'sl-Latn_IT');
         } else {
diff --git a/src/Symfony/Component/Intl/Util/IcuVersion.php b/src/Symfony/Component/Intl/Util/IcuVersion.php
index 1f141224a5..5242fae206 100644
--- a/src/Symfony/Component/Intl/Util/IcuVersion.php
+++ b/src/Symfony/Component/Intl/Util/IcuVersion.php
@@ -91,7 +91,7 @@ class IcuVersion
     {
         $version = preg_replace('/^(\d)\.(\d)/', '$1$2', $version);
 
-        if (1 === strlen($version)) {
+        if (1 === \strlen($version)) {
             $version .= '0';
         }
 
diff --git a/src/Symfony/Component/Ldap/Adapter/AbstractQuery.php b/src/Symfony/Component/Ldap/Adapter/AbstractQuery.php
index 660e52dcb7..4bba5c2ebe 100644
--- a/src/Symfony/Component/Ldap/Adapter/AbstractQuery.php
+++ b/src/Symfony/Component/Ldap/Adapter/AbstractQuery.php
@@ -40,7 +40,7 @@ abstract class AbstractQuery implements QueryInterface
         $resolver->setAllowedValues('scope', array(static::SCOPE_BASE, static::SCOPE_ONE, static::SCOPE_SUB));
 
         $resolver->setNormalizer('filter', function (Options $options, $value) {
-            return is_array($value) ? $value : array($value);
+            return \is_array($value) ? $value : array($value);
         });
 
         $this->connection = $connection;
diff --git a/src/Symfony/Component/Ldap/Adapter/ExtLdap/Adapter.php b/src/Symfony/Component/Ldap/Adapter/ExtLdap/Adapter.php
index 05fbce0b20..fbc41af36b 100644
--- a/src/Symfony/Component/Ldap/Adapter/ExtLdap/Adapter.php
+++ b/src/Symfony/Component/Ldap/Adapter/ExtLdap/Adapter.php
@@ -25,7 +25,7 @@ class Adapter implements AdapterInterface
 
     public function __construct(array $config = array())
     {
-        if (!extension_loaded('ldap')) {
+        if (!\extension_loaded('ldap')) {
             throw new LdapException('The LDAP PHP extension is not enabled.');
         }
 
@@ -76,7 +76,7 @@ class Adapter implements AdapterInterface
             if (!empty($value) && ' ' === $value[0]) {
                 $value = '\\20'.substr($value, 1);
             }
-            if (!empty($value) && ' ' === $value[strlen($value) - 1]) {
+            if (!empty($value) && ' ' === $value[\strlen($value) - 1]) {
                 $value = substr($value, 0, -1).'\\20';
             }
             $value = str_replace("\r", '\0d', $value);
diff --git a/src/Symfony/Component/Ldap/Adapter/ExtLdap/Connection.php b/src/Symfony/Component/Ldap/Adapter/ExtLdap/Connection.php
index 5308d48499..d2453f20d6 100644
--- a/src/Symfony/Component/Ldap/Adapter/ExtLdap/Connection.php
+++ b/src/Symfony/Component/Ldap/Adapter/ExtLdap/Connection.php
@@ -144,7 +144,7 @@ class Connection extends AbstractConnection
 
     private function disconnect()
     {
-        if ($this->connection && is_resource($this->connection)) {
+        if ($this->connection && \is_resource($this->connection)) {
             ldap_unbind($this->connection);
         }
 
diff --git a/src/Symfony/Component/Ldap/Adapter/ExtLdap/ConnectionOptions.php b/src/Symfony/Component/Ldap/Adapter/ExtLdap/ConnectionOptions.php
index 6d878aa699..c03171eb66 100644
--- a/src/Symfony/Component/Ldap/Adapter/ExtLdap/ConnectionOptions.php
+++ b/src/Symfony/Component/Ldap/Adapter/ExtLdap/ConnectionOptions.php
@@ -64,15 +64,15 @@ final class ConnectionOptions
         // Convert
         $constantName = self::getOptionName($name);
 
-        if (!defined($constantName)) {
+        if (!\defined($constantName)) {
             throw new LdapException(sprintf('Unknown option "%s".', $name));
         }
 
-        return constant($constantName);
+        return \constant($constantName);
     }
 
     public static function isOption($name)
     {
-        return defined(self::getOptionName($name));
+        return \defined(self::getOptionName($name));
     }
 }
diff --git a/src/Symfony/Component/Ldap/Adapter/ExtLdap/UpdateOperation.php b/src/Symfony/Component/Ldap/Adapter/ExtLdap/UpdateOperation.php
index bb5d146b9e..7bf3d32f37 100644
--- a/src/Symfony/Component/Ldap/Adapter/ExtLdap/UpdateOperation.php
+++ b/src/Symfony/Component/Ldap/Adapter/ExtLdap/UpdateOperation.php
@@ -34,11 +34,11 @@ class UpdateOperation
      */
     public function __construct(int $operationType, string $attribute, ?array $values)
     {
-        if (!in_array($operationType, $this->validOperationTypes, true)) {
+        if (!\in_array($operationType, $this->validOperationTypes, true)) {
             throw new UpdateOperationException(sprintf('"%s" is not a valid modification type.', $operationType));
         }
         if (LDAP_MODIFY_BATCH_REMOVE_ALL === $operationType && null !== $values) {
-            throw new UpdateOperationException(sprintf('$values must be null for LDAP_MODIFY_BATCH_REMOVE_ALL operation, "%s" given.', gettype($values)));
+            throw new UpdateOperationException(sprintf('$values must be null for LDAP_MODIFY_BATCH_REMOVE_ALL operation, "%s" given.', \gettype($values)));
         }
 
         $this->operationType = $operationType;
diff --git a/src/Symfony/Component/Lock/Store/CombinedStore.php b/src/Symfony/Component/Lock/Store/CombinedStore.php
index 50258fe694..ab8b30da87 100644
--- a/src/Symfony/Component/Lock/Store/CombinedStore.php
+++ b/src/Symfony/Component/Lock/Store/CombinedStore.php
@@ -46,7 +46,7 @@ class CombinedStore implements StoreInterface, LoggerAwareInterface
     {
         foreach ($stores as $store) {
             if (!$store instanceof StoreInterface) {
-                throw new InvalidArgumentException(sprintf('The store must implement "%s". Got "%s".', StoreInterface::class, get_class($store)));
+                throw new InvalidArgumentException(sprintf('The store must implement "%s". Got "%s".', StoreInterface::class, \get_class($store)));
             }
         }
 
@@ -62,7 +62,7 @@ class CombinedStore implements StoreInterface, LoggerAwareInterface
     {
         $successCount = 0;
         $failureCount = 0;
-        $storesCount = count($this->stores);
+        $storesCount = \count($this->stores);
 
         foreach ($this->stores as $store) {
             try {
@@ -92,7 +92,7 @@ class CombinedStore implements StoreInterface, LoggerAwareInterface
 
     public function waitAndSave(Key $key)
     {
-        throw new NotSupportedException(sprintf('The store "%s" does not supports blocking locks.', get_class($this)));
+        throw new NotSupportedException(sprintf('The store "%s" does not supports blocking locks.', \get_class($this)));
     }
 
     /**
@@ -102,7 +102,7 @@ class CombinedStore implements StoreInterface, LoggerAwareInterface
     {
         $successCount = 0;
         $failureCount = 0;
-        $storesCount = count($this->stores);
+        $storesCount = \count($this->stores);
         $expireAt = microtime(true) + $ttl;
 
         foreach ($this->stores as $store) {
@@ -164,7 +164,7 @@ class CombinedStore implements StoreInterface, LoggerAwareInterface
     {
         $successCount = 0;
         $failureCount = 0;
-        $storesCount = count($this->stores);
+        $storesCount = \count($this->stores);
 
         foreach ($this->stores as $store) {
             if ($store->exists($key)) {
diff --git a/src/Symfony/Component/Lock/Store/MemcachedStore.php b/src/Symfony/Component/Lock/Store/MemcachedStore.php
index f1c5c11208..fc504ca856 100644
--- a/src/Symfony/Component/Lock/Store/MemcachedStore.php
+++ b/src/Symfony/Component/Lock/Store/MemcachedStore.php
@@ -31,7 +31,7 @@ class MemcachedStore implements StoreInterface
 
     public static function isSupported()
     {
-        return extension_loaded('memcached');
+        return \extension_loaded('memcached');
     }
 
     /**
@@ -71,7 +71,7 @@ class MemcachedStore implements StoreInterface
 
     public function waitAndSave(Key $key)
     {
-        throw new InvalidArgumentException(sprintf('The store "%s" does not supports blocking locks.', get_class($this)));
+        throw new InvalidArgumentException(sprintf('The store "%s" does not supports blocking locks.', \get_class($this)));
     }
 
     /**
diff --git a/src/Symfony/Component/Lock/Store/RedisStore.php b/src/Symfony/Component/Lock/Store/RedisStore.php
index 291e0f5254..6d7958beef 100644
--- a/src/Symfony/Component/Lock/Store/RedisStore.php
+++ b/src/Symfony/Component/Lock/Store/RedisStore.php
@@ -35,7 +35,7 @@ class RedisStore implements StoreInterface
     public function __construct($redisClient, float $initialTtl = 300.0)
     {
         if (!$redisClient instanceof \Redis && !$redisClient instanceof \RedisArray && !$redisClient instanceof \RedisCluster && !$redisClient instanceof \Predis\Client && !$redisClient instanceof RedisProxy) {
-            throw new InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, is_object($redisClient) ? get_class($redisClient) : gettype($redisClient)));
+            throw new InvalidArgumentException(sprintf('%s() expects parameter 1 to be Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, \is_object($redisClient) ? \get_class($redisClient) : \gettype($redisClient)));
         }
 
         if ($initialTtl <= 0) {
@@ -71,7 +71,7 @@ class RedisStore implements StoreInterface
 
     public function waitAndSave(Key $key)
     {
-        throw new InvalidArgumentException(sprintf('The store "%s" does not supports blocking locks.', get_class($this)));
+        throw new InvalidArgumentException(sprintf('The store "%s" does not supports blocking locks.', \get_class($this)));
     }
 
     /**
@@ -137,10 +137,10 @@ class RedisStore implements StoreInterface
         }
 
         if ($this->redis instanceof \Predis\Client) {
-            return call_user_func_array(array($this->redis, 'eval'), array_merge(array($script, 1, $resource), $args));
+            return \call_user_func_array(array($this->redis, 'eval'), array_merge(array($script, 1, $resource), $args));
         }
 
-        throw new InvalidArgumentException(sprintf('%s() expects been initialized with a Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, is_object($this->redis) ? get_class($this->redis) : gettype($this->redis)));
+        throw new InvalidArgumentException(sprintf('%s() expects been initialized with a Redis, RedisArray, RedisCluster or Predis\Client, %s given', __METHOD__, \is_object($this->redis) ? \get_class($this->redis) : \gettype($this->redis)));
     }
 
     /**
diff --git a/src/Symfony/Component/Lock/Store/SemaphoreStore.php b/src/Symfony/Component/Lock/Store/SemaphoreStore.php
index 6a32a303f4..47f8616b0a 100644
--- a/src/Symfony/Component/Lock/Store/SemaphoreStore.php
+++ b/src/Symfony/Component/Lock/Store/SemaphoreStore.php
@@ -32,7 +32,7 @@ class SemaphoreStore implements StoreInterface
      */
     public static function isSupported()
     {
-        return extension_loaded('sysvsem');
+        return \extension_loaded('sysvsem');
     }
 
     public function __construct()
diff --git a/src/Symfony/Component/Lock/Store/StoreFactory.php b/src/Symfony/Component/Lock/Store/StoreFactory.php
index a768d19746..cbbcb685c3 100644
--- a/src/Symfony/Component/Lock/Store/StoreFactory.php
+++ b/src/Symfony/Component/Lock/Store/StoreFactory.php
@@ -35,6 +35,6 @@ class StoreFactory
             return new MemcachedStore($connection);
         }
 
-        throw new InvalidArgumentException(sprintf('Unsupported Connection: %s.', get_class($connection)));
+        throw new InvalidArgumentException(sprintf('Unsupported Connection: %s.', \get_class($connection)));
     }
 }
diff --git a/src/Symfony/Component/Messenger/DataCollector/MessengerDataCollector.php b/src/Symfony/Component/Messenger/DataCollector/MessengerDataCollector.php
index d71f16d544..539f774ff0 100644
--- a/src/Symfony/Component/Messenger/DataCollector/MessengerDataCollector.php
+++ b/src/Symfony/Component/Messenger/DataCollector/MessengerDataCollector.php
@@ -103,7 +103,7 @@ class MessengerDataCollector extends DataCollector implements LateDataCollectorI
         if (array_key_exists('result', $tracedMessage)) {
             $result = $tracedMessage['result'];
             $debugRepresentation['result'] = array(
-                'type' => \is_object($result) ? \get_class($result) : gettype($result),
+                'type' => \is_object($result) ? \get_class($result) : \gettype($result),
                 'value' => $result,
             );
         }
diff --git a/src/Symfony/Component/Messenger/Tests/Command/DebugCommandTest.php b/src/Symfony/Component/Messenger/Tests/Command/DebugCommandTest.php
index deb01cf474..fd52a5d039 100644
--- a/src/Symfony/Component/Messenger/Tests/Command/DebugCommandTest.php
+++ b/src/Symfony/Component/Messenger/Tests/Command/DebugCommandTest.php
@@ -28,7 +28,7 @@ class DebugCommandTest extends TestCase
 {
     protected function setUp()
     {
-        putenv('COLUMNS='.(119 + strlen(PHP_EOL)));
+        putenv('COLUMNS='.(119 + \strlen(PHP_EOL)));
     }
 
     protected function tearDown()
diff --git a/src/Symfony/Component/Messenger/Transport/AmqpExt/Connection.php b/src/Symfony/Component/Messenger/Transport/AmqpExt/Connection.php
index 03258d0286..6f50bd76d5 100644
--- a/src/Symfony/Component/Messenger/Transport/AmqpExt/Connection.php
+++ b/src/Symfony/Component/Messenger/Transport/AmqpExt/Connection.php
@@ -218,6 +218,6 @@ class Connection
 
     private function shouldSetup(): bool
     {
-        return !array_key_exists('auto-setup', $this->connectionCredentials) || !in_array($this->connectionCredentials['auto-setup'], array(false, 'false'), true);
+        return !array_key_exists('auto-setup', $this->connectionCredentials) || !\in_array($this->connectionCredentials['auto-setup'], array(false, 'false'), true);
     }
 }
diff --git a/src/Symfony/Component/OptionsResolver/Debug/OptionsResolverIntrospector.php b/src/Symfony/Component/OptionsResolver/Debug/OptionsResolverIntrospector.php
index 4d9699df4c..dca9cb496b 100644
--- a/src/Symfony/Component/OptionsResolver/Debug/OptionsResolverIntrospector.php
+++ b/src/Symfony/Component/OptionsResolver/Debug/OptionsResolverIntrospector.php
@@ -47,7 +47,7 @@ class OptionsResolverIntrospector
      */
     public function getDefault(string $option)
     {
-        return call_user_func($this->get, 'defaults', $option, sprintf('No default value was set for the "%s" option.', $option));
+        return \call_user_func($this->get, 'defaults', $option, sprintf('No default value was set for the "%s" option.', $option));
     }
 
     /**
@@ -57,7 +57,7 @@ class OptionsResolverIntrospector
      */
     public function getLazyClosures(string $option): array
     {
-        return call_user_func($this->get, 'lazy', $option, sprintf('No lazy closures were set for the "%s" option.', $option));
+        return \call_user_func($this->get, 'lazy', $option, sprintf('No lazy closures were set for the "%s" option.', $option));
     }
 
     /**
@@ -67,7 +67,7 @@ class OptionsResolverIntrospector
      */
     public function getAllowedTypes(string $option): array
     {
-        return call_user_func($this->get, 'allowedTypes', $option, sprintf('No allowed types were set for the "%s" option.', $option));
+        return \call_user_func($this->get, 'allowedTypes', $option, sprintf('No allowed types were set for the "%s" option.', $option));
     }
 
     /**
@@ -77,7 +77,7 @@ class OptionsResolverIntrospector
      */
     public function getAllowedValues(string $option): array
     {
-        return call_user_func($this->get, 'allowedValues', $option, sprintf('No allowed values were set for the "%s" option.', $option));
+        return \call_user_func($this->get, 'allowedValues', $option, sprintf('No allowed values were set for the "%s" option.', $option));
     }
 
     /**
@@ -85,6 +85,6 @@ class OptionsResolverIntrospector
      */
     public function getNormalizer(string $option): \Closure
     {
-        return call_user_func($this->get, 'normalizers', $option, sprintf('No normalizer was set for the "%s" option.', $option));
+        return \call_user_func($this->get, 'normalizers', $option, sprintf('No normalizer was set for the "%s" option.', $option));
     }
 }
diff --git a/src/Symfony/Component/OptionsResolver/OptionsResolver.php b/src/Symfony/Component/OptionsResolver/OptionsResolver.php
index ef8347a80b..ddaef9a73c 100644
--- a/src/Symfony/Component/OptionsResolver/OptionsResolver.php
+++ b/src/Symfony/Component/OptionsResolver/OptionsResolver.php
@@ -535,7 +535,7 @@ class OptionsResolver implements Options
             ));
         }
 
-        if (!is_array($allowedValues)) {
+        if (!\is_array($allowedValues)) {
             $allowedValues = array($allowedValues);
         }
 
@@ -718,12 +718,12 @@ class OptionsResolver implements Options
         // Make sure that no unknown options are passed
         $diff = array_diff_key($options, $clone->defined);
 
-        if (count($diff) > 0) {
+        if (\count($diff) > 0) {
             ksort($clone->defined);
             ksort($diff);
 
             throw new UndefinedOptionsException(sprintf(
-                (count($diff) > 1 ? 'The options "%s" do not exist.' : 'The option "%s" does not exist.').' Defined options are: "%s".',
+                (\count($diff) > 1 ? 'The options "%s" do not exist.' : 'The option "%s" does not exist.').' Defined options are: "%s".',
                 implode('", "', array_keys($diff)),
                 implode('", "', array_keys($clone->defined))
             ));
@@ -738,11 +738,11 @@ class OptionsResolver implements Options
         // Check whether any required option is missing
         $diff = array_diff_key($clone->required, $clone->defaults);
 
-        if (count($diff) > 0) {
+        if (\count($diff) > 0) {
             ksort($diff);
 
             throw new MissingOptionsException(sprintf(
-                count($diff) > 1 ? 'The required options "%s" are missing.' : 'The required option "%s" is missing.',
+                \count($diff) > 1 ? 'The required options "%s" are missing.' : 'The required option "%s" is missing.',
                 implode('", "', array_keys($diff))
             ));
         }
@@ -882,7 +882,7 @@ class OptionsResolver implements Options
                     $this->formatValue($value)
                 );
 
-                if (count($printableAllowedValues) > 0) {
+                if (\count($printableAllowedValues) > 0) {
                     $message .= sprintf(
                         ' Accepted values are: %s.',
                         $this->formatValues($printableAllowedValues)
@@ -1049,7 +1049,7 @@ class OptionsResolver implements Options
             throw new AccessException('Counting is only supported within closures of lazy options and normalizers.');
         }
 
-        return count($this->defaults);
+        return \count($this->defaults);
     }
 
     /**
@@ -1088,7 +1088,7 @@ class OptionsResolver implements Options
             }
         }
 
-        return (\is_object($value) ? get_class($value) : gettype($value)).$suffix;
+        return (\is_object($value) ? \get_class($value) : \gettype($value)).$suffix;
     }
 
     /**
@@ -1103,7 +1103,7 @@ class OptionsResolver implements Options
     private function formatValue($value): string
     {
         if (\is_object($value)) {
-            return get_class($value);
+            return \get_class($value);
         }
 
         if (\is_array($value)) {
@@ -1152,7 +1152,7 @@ class OptionsResolver implements Options
 
     private static function isValueValidType(string $type, $value): bool
     {
-        return (function_exists($isFunction = 'is_'.$type) && $isFunction($value)) || $value instanceof $type;
+        return (\function_exists($isFunction = 'is_'.$type) && $isFunction($value)) || $value instanceof $type;
     }
 
     private function getInvalidValues(array $arrayValues, string $type): array
diff --git a/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php b/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php
index 06eedb58f4..2ed6face53 100644
--- a/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php
+++ b/src/Symfony/Component/OptionsResolver/Tests/OptionsResolverTest.php
@@ -1765,7 +1765,7 @@ class OptionsResolverTest extends TestCase
         $this->resolver->setDefined('bar');
         $this->resolver->setDefault('lazy1', function () {});
 
-        count($this->resolver);
+        \count($this->resolver);
     }
 
     public function testNestedArrays()
diff --git a/src/Symfony/Component/Process/Pipes/AbstractPipes.php b/src/Symfony/Component/Process/Pipes/AbstractPipes.php
index 9a7d88be89..e5e26866af 100644
--- a/src/Symfony/Component/Process/Pipes/AbstractPipes.php
+++ b/src/Symfony/Component/Process/Pipes/AbstractPipes.php
@@ -32,9 +32,9 @@ abstract class AbstractPipes implements PipesInterface
      */
     public function __construct($input)
     {
-        if (is_resource($input) || $input instanceof \Iterator) {
+        if (\is_resource($input) || $input instanceof \Iterator) {
             $this->input = $input;
-        } elseif (is_string($input)) {
+        } elseif (\is_string($input)) {
             $this->inputBuffer = $input;
         } else {
             $this->inputBuffer = (string) $input;
@@ -78,7 +78,7 @@ abstract class AbstractPipes implements PipesInterface
         foreach ($this->pipes as $pipe) {
             stream_set_blocking($pipe, 0);
         }
-        if (is_resource($this->input)) {
+        if (\is_resource($this->input)) {
             stream_set_blocking($this->input, 0);
         }
 
@@ -100,12 +100,12 @@ abstract class AbstractPipes implements PipesInterface
         if ($input instanceof \Iterator) {
             if (!$input->valid()) {
                 $input = null;
-            } elseif (is_resource($input = $input->current())) {
+            } elseif (\is_resource($input = $input->current())) {
                 stream_set_blocking($input, 0);
             } elseif (!isset($this->inputBuffer[0])) {
-                if (!is_string($input)) {
+                if (!\is_string($input)) {
                     if (!is_scalar($input)) {
-                        throw new InvalidArgumentException(sprintf('%s yielded a value of type "%s", but only scalars and stream resources are supported', get_class($this->input), gettype($input)));
+                        throw new InvalidArgumentException(sprintf('%s yielded a value of type "%s", but only scalars and stream resources are supported', \get_class($this->input), \gettype($input)));
                     }
                     $input = (string) $input;
                 }
diff --git a/src/Symfony/Component/Process/Pipes/WindowsPipes.php b/src/Symfony/Component/Process/Pipes/WindowsPipes.php
index 845d2bf70e..0a1488f98c 100644
--- a/src/Symfony/Component/Process/Pipes/WindowsPipes.php
+++ b/src/Symfony/Component/Process/Pipes/WindowsPipes.php
@@ -141,7 +141,7 @@ class WindowsPipes extends AbstractPipes
             $data = stream_get_contents($fileHandle, -1, $this->readBytes[$type]);
 
             if (isset($data[0])) {
-                $this->readBytes[$type] += strlen($data);
+                $this->readBytes[$type] += \strlen($data);
                 $read[$type] = $data;
             }
             if ($close) {
diff --git a/src/Symfony/Component/Process/Process.php b/src/Symfony/Component/Process/Process.php
index d65c6ac92c..d8e783ec7b 100644
--- a/src/Symfony/Component/Process/Process.php
+++ b/src/Symfony/Component/Process/Process.php
@@ -139,7 +139,7 @@ class Process implements \IteratorAggregate
      */
     public function __construct($command, string $cwd = null, array $env = null, $input = null, ?float $timeout = 60)
     {
-        if (!function_exists('proc_open')) {
+        if (!\function_exists('proc_open')) {
             throw new RuntimeException('The Process class relies on proc_open, which is not available on your PHP installation.');
         }
 
@@ -154,7 +154,7 @@ class Process implements \IteratorAggregate
         // on Gnu/Linux, PHP builds with --enable-maintainer-zts are also affected
         // @see : https://bugs.php.net/bug.php?id=51800
         // @see : https://bugs.php.net/bug.php?id=50524
-        if (null === $this->cwd && (defined('ZEND_THREAD_SAFE') || '\\' === DIRECTORY_SEPARATOR)) {
+        if (null === $this->cwd && (\defined('ZEND_THREAD_SAFE') || '\\' === DIRECTORY_SEPARATOR)) {
             $this->cwd = getcwd();
         }
         if (null !== $env) {
@@ -291,7 +291,7 @@ class Process implements \IteratorAggregate
         $this->hasCallback = null !== $callback;
         $descriptors = $this->getDescriptors();
 
-        if (is_array($commandline = $this->commandline)) {
+        if (\is_array($commandline = $this->commandline)) {
             $commandline = implode(' ', array_map(array($this, 'escapeArgument'), $commandline));
 
             if ('\\' !== DIRECTORY_SEPARATOR) {
@@ -336,7 +336,7 @@ class Process implements \IteratorAggregate
 
         $this->process = proc_open($commandline, $descriptors, $this->processPipes->pipes, $this->cwd, $envPairs, $options);
 
-        if (!is_resource($this->process)) {
+        if (!\is_resource($this->process)) {
             throw new RuntimeException('Unable to launch a new process.');
         }
         $this->status = self::STATUS_STARTED;
@@ -916,7 +916,7 @@ class Process implements \IteratorAggregate
      */
     public function getCommandLine()
     {
-        return is_array($this->commandline) ? implode(' ', array_map(array($this, 'escapeArgument'), $this->commandline)) : $this->commandline;
+        return \is_array($this->commandline) ? implode(' ', array_map(array($this, 'escapeArgument'), $this->commandline)) : $this->commandline;
     }
 
     /**
@@ -1115,7 +1115,7 @@ class Process implements \IteratorAggregate
     {
         // Process can not handle env values that are arrays
         $env = array_filter($env, function ($value) {
-            return !is_array($value);
+            return !\is_array($value);
         });
 
         $this->env = $env;
@@ -1264,7 +1264,7 @@ class Process implements \IteratorAggregate
         if ($this->outputDisabled) {
             return function ($type, $data) use ($callback) {
                 if (null !== $callback) {
-                    call_user_func($callback, $type, $data);
+                    \call_user_func($callback, $type, $data);
                 }
             };
         }
@@ -1279,7 +1279,7 @@ class Process implements \IteratorAggregate
             }
 
             if (null !== $callback) {
-                call_user_func($callback, $type, $data);
+                \call_user_func($callback, $type, $data);
             }
         };
     }
@@ -1320,7 +1320,7 @@ class Process implements \IteratorAggregate
             return self::$sigchild;
         }
 
-        if (!function_exists('phpinfo')) {
+        if (!\function_exists('phpinfo')) {
             return self::$sigchild = false;
         }
 
@@ -1395,7 +1395,7 @@ class Process implements \IteratorAggregate
     private function close(): int
     {
         $this->processPipes->close();
-        if (is_resource($this->process)) {
+        if (\is_resource($this->process)) {
             proc_close($this->process);
         }
         $this->exitcode = $this->processInformation['exitcode'];
@@ -1472,7 +1472,7 @@ class Process implements \IteratorAggregate
         } else {
             if (!$this->isSigchildEnabled()) {
                 $ok = @proc_terminate($this->process, $signal);
-            } elseif (function_exists('posix_kill')) {
+            } elseif (\function_exists('posix_kill')) {
                 $ok = @posix_kill($pid, $signal);
             } elseif ($ok = proc_open(sprintf('kill -%d %d', $signal, $pid), array(2 => array('pipe', 'w')), $pipes)) {
                 $ok = false === fgets($pipes[2]);
@@ -1591,13 +1591,13 @@ class Process implements \IteratorAggregate
         $env = array();
 
         foreach ($_SERVER as $k => $v) {
-            if (is_string($v) && false !== $v = getenv($k)) {
+            if (\is_string($v) && false !== $v = getenv($k)) {
                 $env[$k] = $v;
             }
         }
 
         foreach ($_ENV as $k => $v) {
-            if (is_string($v)) {
+            if (\is_string($v)) {
                 $env[$k] = $v;
             }
         }
diff --git a/src/Symfony/Component/Process/ProcessUtils.php b/src/Symfony/Component/Process/ProcessUtils.php
index e0d9c08ab4..2f9c4be4de 100644
--- a/src/Symfony/Component/Process/ProcessUtils.php
+++ b/src/Symfony/Component/Process/ProcessUtils.php
@@ -42,10 +42,10 @@ class ProcessUtils
     public static function validateInput($caller, $input)
     {
         if (null !== $input) {
-            if (is_resource($input)) {
+            if (\is_resource($input)) {
                 return $input;
             }
-            if (is_string($input)) {
+            if (\is_string($input)) {
                 return $input;
             }
             if (is_scalar($input)) {
diff --git a/src/Symfony/Component/Process/Tests/ExecutableFinderTest.php b/src/Symfony/Component/Process/Tests/ExecutableFinderTest.php
index 3b2500b7fc..9b1890ff58 100644
--- a/src/Symfony/Component/Process/Tests/ExecutableFinderTest.php
+++ b/src/Symfony/Component/Process/Tests/ExecutableFinderTest.php
@@ -41,7 +41,7 @@ class ExecutableFinderTest extends TestCase
             $this->markTestSkipped('Cannot test when open_basedir is set');
         }
 
-        $this->setPath(dirname(PHP_BINARY));
+        $this->setPath(\dirname(PHP_BINARY));
 
         $finder = new ExecutableFinder();
         $result = $finder->find($this->getPhpBinaryName());
@@ -73,7 +73,7 @@ class ExecutableFinderTest extends TestCase
 
         $this->setPath('');
 
-        $extraDirs = array(dirname(PHP_BINARY));
+        $extraDirs = array(\dirname(PHP_BINARY));
 
         $finder = new ExecutableFinder();
         $result = $finder->find($this->getPhpBinaryName(), null, $extraDirs);
@@ -91,7 +91,7 @@ class ExecutableFinderTest extends TestCase
             $this->markTestSkipped('Cannot test when open_basedir is set');
         }
 
-        $this->iniSet('open_basedir', dirname(PHP_BINARY).PATH_SEPARATOR.'/');
+        $this->iniSet('open_basedir', \dirname(PHP_BINARY).PATH_SEPARATOR.'/');
 
         $finder = new ExecutableFinder();
         $result = $finder->find($this->getPhpBinaryName());
diff --git a/src/Symfony/Component/Process/Tests/PipeStdinInStdoutStdErrStreamSelect.php b/src/Symfony/Component/Process/Tests/PipeStdinInStdoutStdErrStreamSelect.php
index bbd7ddfeb2..1ea0e127f7 100644
--- a/src/Symfony/Component/Process/Tests/PipeStdinInStdoutStdErrStreamSelect.php
+++ b/src/Symfony/Component/Process/Tests/PipeStdinInStdoutStdErrStreamSelect.php
@@ -35,22 +35,22 @@ while ($read || $write) {
     }
 
     if (in_array(STDOUT, $w) && strlen($out) > 0) {
-        $written = fwrite(STDOUT, (binary) $out, 32768);
+        $written = fwrite(STDOUT, (string) $out, 32768);
         if (false === $written) {
             die(ERR_WRITE_FAILED);
         }
-        $out = (binary) substr($out, $written);
+        $out = (string) substr($out, $written);
     }
     if (null === $read && '' === $out) {
         $write = array_diff($write, array(STDOUT));
     }
 
     if (in_array(STDERR, $w) && strlen($err) > 0) {
-        $written = fwrite(STDERR, (binary) $err, 32768);
+        $written = fwrite(STDERR, (string) $err, 32768);
         if (false === $written) {
             die(ERR_WRITE_FAILED);
         }
-        $err = (binary) substr($err, $written);
+        $err = (string) substr($err, $written);
     }
     if (null === $read && '' === $err) {
         $write = array_diff($write, array(STDERR));
diff --git a/src/Symfony/Component/Process/Tests/ProcessTest.php b/src/Symfony/Component/Process/Tests/ProcessTest.php
index 2492ceb88d..3b1dc232bf 100644
--- a/src/Symfony/Component/Process/Tests/ProcessTest.php
+++ b/src/Symfony/Component/Process/Tests/ProcessTest.php
@@ -162,7 +162,7 @@ class ProcessTest extends TestCase
 
         $o = $p->getOutput();
 
-        $this->assertEquals($expectedOutputSize, strlen($o));
+        $this->assertEquals($expectedOutputSize, \strlen($o));
     }
 
     public function testCallbacksAreExecutedWithStart()
@@ -204,8 +204,8 @@ class ProcessTest extends TestCase
         $p->setInput($expected);
         $p->run();
 
-        $this->assertEquals($expectedLength, strlen($p->getOutput()));
-        $this->assertEquals($expectedLength, strlen($p->getErrorOutput()));
+        $this->assertEquals($expectedLength, \strlen($p->getOutput()));
+        $this->assertEquals($expectedLength, \strlen($p->getErrorOutput()));
     }
 
     /**
@@ -226,8 +226,8 @@ class ProcessTest extends TestCase
 
         fclose($stream);
 
-        $this->assertEquals($expectedLength, strlen($p->getOutput()));
-        $this->assertEquals($expectedLength, strlen($p->getErrorOutput()));
+        $this->assertEquals($expectedLength, \strlen($p->getOutput()));
+        $this->assertEquals($expectedLength, \strlen($p->getErrorOutput()));
     }
 
     public function testLiveStreamAsInput()
@@ -567,7 +567,7 @@ class ProcessTest extends TestCase
     {
         $process = $this->getProcess('echo foo');
         $process->run();
-        $this->assertGreaterThan(0, strlen($process->getOutput()));
+        $this->assertGreaterThan(0, \strlen($process->getOutput()));
     }
 
     public function testGetExitCodeIsNullOnStart()
@@ -693,7 +693,7 @@ class ProcessTest extends TestCase
      */
     public function testProcessThrowsExceptionWhenExternallySignaled()
     {
-        if (!function_exists('posix_kill')) {
+        if (!\function_exists('posix_kill')) {
             $this->markTestSkipped('Function posix_kill is required.');
         }
 
diff --git a/src/Symfony/Component/PropertyAccess/Exception/UnexpectedTypeException.php b/src/Symfony/Component/PropertyAccess/Exception/UnexpectedTypeException.php
index c2b0492130..a7311329a8 100644
--- a/src/Symfony/Component/PropertyAccess/Exception/UnexpectedTypeException.php
+++ b/src/Symfony/Component/PropertyAccess/Exception/UnexpectedTypeException.php
@@ -30,7 +30,7 @@ class UnexpectedTypeException extends RuntimeException
         $message = sprintf(
             'PropertyAccessor requires a graph of objects or arrays to operate on, '.
             'but it found type "%s" while trying to traverse path "%s" at property "%s".',
-            gettype($value),
+            \gettype($value),
             (string) $path,
             $path->getElement($pathIndex)
         );
diff --git a/src/Symfony/Component/PropertyAccess/PropertyAccessor.php b/src/Symfony/Component/PropertyAccess/PropertyAccessor.php
index bb959223c4..01a66e05bc 100644
--- a/src/Symfony/Component/PropertyAccess/PropertyAccessor.php
+++ b/src/Symfony/Component/PropertyAccess/PropertyAccessor.php
@@ -89,7 +89,7 @@ class PropertyAccessor implements PropertyAccessorInterface
         );
         $propertyValues = $this->readPropertiesUntil($zval, $propertyPath, $propertyPath->getLength(), $this->ignoreInvalidIndices);
 
-        return $propertyValues[count($propertyValues) - 1][self::VALUE];
+        return $propertyValues[\count($propertyValues) - 1][self::VALUE];
     }
 
     /**
@@ -107,7 +107,7 @@ class PropertyAccessor implements PropertyAccessorInterface
         $overwrite = true;
 
         try {
-            for ($i = count($propertyValues) - 1; 0 <= $i; --$i) {
+            for ($i = \count($propertyValues) - 1; 0 <= $i; --$i) {
                 $zval = $propertyValues[$i];
                 unset($propertyValues[$i]);
 
@@ -143,7 +143,7 @@ class PropertyAccessor implements PropertyAccessorInterface
                     // if current element's reference chain is not broken - current element
                     // as well as all its ancients in the property path are all passed by reference,
                     // then there is no need to continue the value setting process
-                    if (is_object($zval[self::VALUE]) || isset($zval[self::IS_REF_CHAINED])) {
+                    if (\is_object($zval[self::VALUE]) || isset($zval[self::IS_REF_CHAINED])) {
                         break;
                     }
                 }
@@ -162,9 +162,9 @@ class PropertyAccessor implements PropertyAccessorInterface
     {
         if (isset($trace[$i]['file']) && __FILE__ === $trace[$i]['file'] && isset($trace[$i]['args'][0])) {
             $pos = strpos($message, $delim = 'must be of the type ') ?: (strpos($message, $delim = 'must be an instance of ') ?: strpos($message, $delim = 'must implement interface '));
-            $pos += strlen($delim);
+            $pos += \strlen($delim);
             $type = $trace[$i]['args'][0];
-            $type = is_object($type) ? get_class($type) : gettype($type);
+            $type = \is_object($type) ? \get_class($type) : \gettype($type);
 
             throw new InvalidArgumentException(sprintf('Expected argument of type "%s", "%s" given at property path "%s".', substr($message, $pos, strpos($message, ',', $pos) - $pos), $type, $propertyPath));
         }
@@ -206,12 +206,12 @@ class PropertyAccessor implements PropertyAccessorInterface
             );
             $propertyValues = $this->readPropertiesUntil($zval, $propertyPath, $propertyPath->getLength() - 1);
 
-            for ($i = count($propertyValues) - 1; 0 <= $i; --$i) {
+            for ($i = \count($propertyValues) - 1; 0 <= $i; --$i) {
                 $zval = $propertyValues[$i];
                 unset($propertyValues[$i]);
 
                 if ($propertyPath->isIndex($i)) {
-                    if (!$zval[self::VALUE] instanceof \ArrayAccess && !is_array($zval[self::VALUE])) {
+                    if (!$zval[self::VALUE] instanceof \ArrayAccess && !\is_array($zval[self::VALUE])) {
                         return false;
                     }
                 } else {
@@ -220,7 +220,7 @@ class PropertyAccessor implements PropertyAccessorInterface
                     }
                 }
 
-                if (is_object($zval[self::VALUE])) {
+                if (\is_object($zval[self::VALUE])) {
                     return true;
                 }
             }
@@ -248,7 +248,7 @@ class PropertyAccessor implements PropertyAccessorInterface
      */
     private function readPropertiesUntil($zval, PropertyPathInterface $propertyPath, $lastIndex, $ignoreInvalidIndices = true)
     {
-        if (!is_object($zval[self::VALUE]) && !is_array($zval[self::VALUE])) {
+        if (!\is_object($zval[self::VALUE]) && !\is_array($zval[self::VALUE])) {
             throw new UnexpectedTypeException($zval[self::VALUE], $propertyPath, 0);
         }
 
@@ -262,10 +262,10 @@ class PropertyAccessor implements PropertyAccessorInterface
             if ($isIndex) {
                 // Create missing nested arrays on demand
                 if (($zval[self::VALUE] instanceof \ArrayAccess && !$zval[self::VALUE]->offsetExists($property)) ||
-                    (is_array($zval[self::VALUE]) && !isset($zval[self::VALUE][$property]) && !array_key_exists($property, $zval[self::VALUE]))
+                    (\is_array($zval[self::VALUE]) && !isset($zval[self::VALUE][$property]) && !array_key_exists($property, $zval[self::VALUE]))
                 ) {
                     if (!$ignoreInvalidIndices) {
-                        if (!is_array($zval[self::VALUE])) {
+                        if (!\is_array($zval[self::VALUE])) {
                             if (!$zval[self::VALUE] instanceof \Traversable) {
                                 throw new NoSuchIndexException(sprintf(
                                     'Cannot read index "%s" while trying to traverse path "%s".',
@@ -301,7 +301,7 @@ class PropertyAccessor implements PropertyAccessorInterface
             }
 
             // the final value of the path must not be validated
-            if ($i + 1 < $propertyPath->getLength() && !is_object($zval[self::VALUE]) && !is_array($zval[self::VALUE])) {
+            if ($i + 1 < $propertyPath->getLength() && !\is_object($zval[self::VALUE]) && !\is_array($zval[self::VALUE])) {
                 throw new UnexpectedTypeException($zval[self::VALUE], $propertyPath, $i + 1);
             }
 
@@ -332,8 +332,8 @@ class PropertyAccessor implements PropertyAccessorInterface
      */
     private function readIndex($zval, $index)
     {
-        if (!$zval[self::VALUE] instanceof \ArrayAccess && !is_array($zval[self::VALUE])) {
-            throw new NoSuchIndexException(sprintf('Cannot read index "%s" from object of type "%s" because it doesn\'t implement \ArrayAccess.', $index, get_class($zval[self::VALUE])));
+        if (!$zval[self::VALUE] instanceof \ArrayAccess && !\is_array($zval[self::VALUE])) {
+            throw new NoSuchIndexException(sprintf('Cannot read index "%s" from object of type "%s" because it doesn\'t implement \ArrayAccess.', $index, \get_class($zval[self::VALUE])));
         }
 
         $result = self::$resultProto;
@@ -343,9 +343,9 @@ class PropertyAccessor implements PropertyAccessorInterface
 
             if (!isset($zval[self::REF])) {
                 // Save creating references when doing read-only lookups
-            } elseif (is_array($zval[self::VALUE])) {
+            } elseif (\is_array($zval[self::VALUE])) {
                 $result[self::REF] = &$zval[self::REF][$index];
-            } elseif (is_object($result[self::VALUE])) {
+            } elseif (\is_object($result[self::VALUE])) {
                 $result[self::REF] = $result[self::VALUE];
             }
         }
@@ -365,13 +365,13 @@ class PropertyAccessor implements PropertyAccessorInterface
      */
     private function readProperty($zval, $property)
     {
-        if (!is_object($zval[self::VALUE])) {
+        if (!\is_object($zval[self::VALUE])) {
             throw new NoSuchPropertyException(sprintf('Cannot read property "%s" from an array. Maybe you intended to write the property path as "[%1$s]" instead.', $property));
         }
 
         $result = self::$resultProto;
         $object = $zval[self::VALUE];
-        $access = $this->getReadAccessInfo(get_class($object), $property);
+        $access = $this->getReadAccessInfo(\get_class($object), $property);
 
         if (self::ACCESS_TYPE_METHOD === $access[self::ACCESS_TYPE]) {
             $result[self::VALUE] = $object->{$access[self::ACCESS_NAME]}();
@@ -400,7 +400,7 @@ class PropertyAccessor implements PropertyAccessorInterface
         }
 
         // Objects are always passed around by reference
-        if (isset($zval[self::REF]) && is_object($result[self::VALUE])) {
+        if (isset($zval[self::REF]) && \is_object($result[self::VALUE])) {
             $result[self::REF] = $result[self::VALUE];
         }
 
@@ -498,8 +498,8 @@ class PropertyAccessor implements PropertyAccessorInterface
      */
     private function writeIndex($zval, $index, $value)
     {
-        if (!$zval[self::VALUE] instanceof \ArrayAccess && !is_array($zval[self::VALUE])) {
-            throw new NoSuchIndexException(sprintf('Cannot modify index "%s" in object of type "%s" because it doesn\'t implement \ArrayAccess.', $index, get_class($zval[self::VALUE])));
+        if (!$zval[self::VALUE] instanceof \ArrayAccess && !\is_array($zval[self::VALUE])) {
+            throw new NoSuchIndexException(sprintf('Cannot modify index "%s" in object of type "%s" because it doesn\'t implement \ArrayAccess.', $index, \get_class($zval[self::VALUE])));
         }
 
         $zval[self::REF][$index] = $value;
@@ -516,12 +516,12 @@ class PropertyAccessor implements PropertyAccessorInterface
      */
     private function writeProperty($zval, $property, $value)
     {
-        if (!is_object($zval[self::VALUE])) {
+        if (!\is_object($zval[self::VALUE])) {
             throw new NoSuchPropertyException(sprintf('Cannot write property "%s" to an array. Maybe you should write the property path as "[%1$s]" instead?', $property));
         }
 
         $object = $zval[self::VALUE];
-        $access = $this->getWriteAccessInfo(get_class($object), $property, $value);
+        $access = $this->getWriteAccessInfo(\get_class($object), $property, $value);
 
         if (self::ACCESS_TYPE_METHOD === $access[self::ACCESS_TYPE]) {
             $object->{$access[self::ACCESS_NAME]}($value);
@@ -540,7 +540,7 @@ class PropertyAccessor implements PropertyAccessorInterface
         } elseif (self::ACCESS_TYPE_MAGIC === $access[self::ACCESS_TYPE]) {
             $object->{$access[self::ACCESS_NAME]}($value);
         } elseif (self::ACCESS_TYPE_NOT_FOUND === $access[self::ACCESS_TYPE]) {
-            throw new NoSuchPropertyException(sprintf('Could not determine access type for property "%s" in class "%s"%s.', $property, get_class($object), isset($access[self::ACCESS_NAME]) ? ': '.$access[self::ACCESS_NAME] : ''));
+            throw new NoSuchPropertyException(sprintf('Could not determine access type for property "%s" in class "%s"%s.', $property, \get_class($object), isset($access[self::ACCESS_NAME]) ? ': '.$access[self::ACCESS_NAME] : ''));
         } else {
             throw new NoSuchPropertyException($access[self::ACCESS_NAME]);
         }
@@ -564,12 +564,12 @@ class PropertyAccessor implements PropertyAccessorInterface
         if ($previousValue instanceof \Traversable) {
             $previousValue = iterator_to_array($previousValue);
         }
-        if ($previousValue && is_array($previousValue)) {
-            if (is_object($collection)) {
+        if ($previousValue && \is_array($previousValue)) {
+            if (\is_object($collection)) {
                 $collection = iterator_to_array($collection);
             }
             foreach ($previousValue as $key => $item) {
-                if (!in_array($item, $collection, true)) {
+                if (!\in_array($item, $collection, true)) {
                     unset($previousValue[$key]);
                     $zval[self::VALUE]->{$removeMethod}($item);
                 }
@@ -579,7 +579,7 @@ class PropertyAccessor implements PropertyAccessorInterface
         }
 
         foreach ($collection as $item) {
-            if (!$previousValue || !in_array($item, $previousValue, true)) {
+            if (!$previousValue || !\in_array($item, $previousValue, true)) {
                 $zval[self::VALUE]->{$addMethod}($item);
             }
         }
@@ -612,7 +612,7 @@ class PropertyAccessor implements PropertyAccessorInterface
         $camelized = $this->camelize($property);
         $singulars = (array) Inflector::singularize($camelized);
 
-        if (is_array($value) || $value instanceof \Traversable) {
+        if (\is_array($value) || $value instanceof \Traversable) {
             $methods = $this->findAdderAndRemover($reflClass, $singulars);
 
             if (null !== $methods) {
@@ -651,7 +651,7 @@ class PropertyAccessor implements PropertyAccessorInterface
                     $property,
                     $reflClass->name,
                     implode('()", "', $methods),
-                    is_object($value) ? get_class($value) : gettype($value)
+                    \is_object($value) ? \get_class($value) : \gettype($value)
                 );
             } else {
                 $access[self::ACCESS_TYPE] = self::ACCESS_TYPE_NOT_FOUND;
@@ -683,11 +683,11 @@ class PropertyAccessor implements PropertyAccessorInterface
      */
     private function isPropertyWritable($object, string $property): bool
     {
-        if (!is_object($object)) {
+        if (!\is_object($object)) {
             return false;
         }
 
-        $access = $this->getWriteAccessInfo(get_class($object), $property, array());
+        $access = $this->getWriteAccessInfo(\get_class($object), $property, array());
 
         return self::ACCESS_TYPE_METHOD === $access[self::ACCESS_TYPE]
             || self::ACCESS_TYPE_PROPERTY === $access[self::ACCESS_TYPE]
diff --git a/src/Symfony/Component/PropertyAccess/PropertyPath.php b/src/Symfony/Component/PropertyAccess/PropertyPath.php
index 51b6599bf3..890b8ffce6 100644
--- a/src/Symfony/Component/PropertyAccess/PropertyPath.php
+++ b/src/Symfony/Component/PropertyAccess/PropertyPath.php
@@ -76,12 +76,12 @@ class PropertyPath implements \IteratorAggregate, PropertyPathInterface
 
             return;
         }
-        if (!is_string($propertyPath)) {
+        if (!\is_string($propertyPath)) {
             throw new InvalidArgumentException(sprintf(
                 'The property path constructor needs a string or an instance of '.
                 '"Symfony\Component\PropertyAccess\PropertyPath". '.
                 'Got: "%s"',
-                is_object($propertyPath) ? get_class($propertyPath) : gettype($propertyPath)
+                \is_object($propertyPath) ? \get_class($propertyPath) : \gettype($propertyPath)
             ));
         }
 
@@ -107,7 +107,7 @@ class PropertyPath implements \IteratorAggregate, PropertyPathInterface
 
             $this->elements[] = $element;
 
-            $position += strlen($matches[1]);
+            $position += \strlen($matches[1]);
             $remaining = $matches[4];
             $pattern = '/^(\.([^\.|\[]++)|\[([^\]]++)\])(.*)/';
         }
@@ -121,7 +121,7 @@ class PropertyPath implements \IteratorAggregate, PropertyPathInterface
             ));
         }
 
-        $this->length = count($this->elements);
+        $this->length = \count($this->elements);
     }
 
     /**
diff --git a/src/Symfony/Component/PropertyAccess/PropertyPathBuilder.php b/src/Symfony/Component/PropertyAccess/PropertyPathBuilder.php
index cecf67300f..12e6f5e524 100644
--- a/src/Symfony/Component/PropertyAccess/PropertyPathBuilder.php
+++ b/src/Symfony/Component/PropertyAccess/PropertyPathBuilder.php
@@ -45,7 +45,7 @@ class PropertyPathBuilder
      */
     public function append($path, $offset = 0, $length = 0)
     {
-        if (is_string($path)) {
+        if (\is_string($path)) {
             $path = new PropertyPath($path);
         }
 
@@ -115,7 +115,7 @@ class PropertyPathBuilder
      */
     public function replace($offset, $length, $path, $pathOffset = 0, $pathLength = 0)
     {
-        if (is_string($path)) {
+        if (\is_string($path)) {
             $path = new PropertyPath($path);
         }
 
@@ -187,7 +187,7 @@ class PropertyPathBuilder
      */
     public function getLength()
     {
-        return count($this->elements);
+        return \count($this->elements);
     }
 
     /**
@@ -240,7 +240,7 @@ class PropertyPathBuilder
             return;
         }
 
-        $length = count($this->elements);
+        $length = \count($this->elements);
 
         if ($cutLength > $insertionLength) {
             // More elements should be removed than inserted
diff --git a/src/Symfony/Component/PropertyAccess/Tests/Fixtures/NonTraversableArrayObject.php b/src/Symfony/Component/PropertyAccess/Tests/Fixtures/NonTraversableArrayObject.php
index fd00a730b8..d2ff935851 100644
--- a/src/Symfony/Component/PropertyAccess/Tests/Fixtures/NonTraversableArrayObject.php
+++ b/src/Symfony/Component/PropertyAccess/Tests/Fixtures/NonTraversableArrayObject.php
@@ -50,7 +50,7 @@ class NonTraversableArrayObject implements \ArrayAccess, \Countable, \Serializab
 
     public function count()
     {
-        return count($this->array);
+        return \count($this->array);
     }
 
     public function serialize()
diff --git a/src/Symfony/Component/PropertyAccess/Tests/Fixtures/TraversableArrayObject.php b/src/Symfony/Component/PropertyAccess/Tests/Fixtures/TraversableArrayObject.php
index 3bd9795e6b..6758f18fbc 100644
--- a/src/Symfony/Component/PropertyAccess/Tests/Fixtures/TraversableArrayObject.php
+++ b/src/Symfony/Component/PropertyAccess/Tests/Fixtures/TraversableArrayObject.php
@@ -55,7 +55,7 @@ class TraversableArrayObject implements \ArrayAccess, \IteratorAggregate, \Count
 
     public function count()
     {
-        return count($this->array);
+        return \count($this->array);
     }
 
     public function serialize()
diff --git a/src/Symfony/Component/PropertyAccess/Tests/PropertyAccessorCollectionTest.php b/src/Symfony/Component/PropertyAccess/Tests/PropertyAccessorCollectionTest.php
index 1f10262305..8a7ab1042b 100644
--- a/src/Symfony/Component/PropertyAccess/Tests/PropertyAccessorCollectionTest.php
+++ b/src/Symfony/Component/PropertyAccess/Tests/PropertyAccessorCollectionTest.php
@@ -105,7 +105,7 @@ abstract class PropertyAccessorCollectionTest extends PropertyAccessorArrayAcces
         $axesBefore = $this->getContainer(array(1 => 'second', 3 => 'fourth', 4 => 'fifth'));
         $axesMerged = $this->getContainer(array(1 => 'first', 2 => 'second', 3 => 'third'));
         $axesAfter = $this->getContainer(array(1 => 'second', 5 => 'first', 6 => 'third'));
-        $axesMergedCopy = is_object($axesMerged) ? clone $axesMerged : $axesMerged;
+        $axesMergedCopy = \is_object($axesMerged) ? clone $axesMerged : $axesMerged;
 
         // Don't use a mock in order to test whether the collections are
         // modified while iterating them
diff --git a/src/Symfony/Component/PropertyInfo/Extractor/ReflectionExtractor.php b/src/Symfony/Component/PropertyInfo/Extractor/ReflectionExtractor.php
index ff6f7cdce1..da106645c3 100644
--- a/src/Symfony/Component/PropertyInfo/Extractor/ReflectionExtractor.php
+++ b/src/Symfony/Component/PropertyInfo/Extractor/ReflectionExtractor.php
@@ -311,7 +311,7 @@ class ReflectionExtractor implements PropertyListExtractorInterface, PropertyTyp
 
         foreach ($this->mutatorPrefixes as $prefix) {
             $names = array($ucProperty);
-            if (in_array($prefix, $this->arrayMutatorPrefixes)) {
+            if (\in_array($prefix, $this->arrayMutatorPrefixes)) {
                 $names = array_merge($names, $ucSingulars);
             }
 
@@ -340,7 +340,7 @@ class ReflectionExtractor implements PropertyListExtractorInterface, PropertyTyp
         $pattern = implode('|', array_merge($this->accessorPrefixes, $this->mutatorPrefixes));
 
         if ('' !== $pattern && preg_match('/^('.$pattern.')(.+)$/i', $methodName, $matches)) {
-            if (!in_array($matches[1], $this->arrayMutatorPrefixes)) {
+            if (!\in_array($matches[1], $this->arrayMutatorPrefixes)) {
                 return $matches[2];
             }
 
diff --git a/src/Symfony/Component/PropertyInfo/Extractor/SerializerExtractor.php b/src/Symfony/Component/PropertyInfo/Extractor/SerializerExtractor.php
index 6afbb542e1..7a311e6b08 100644
--- a/src/Symfony/Component/PropertyInfo/Extractor/SerializerExtractor.php
+++ b/src/Symfony/Component/PropertyInfo/Extractor/SerializerExtractor.php
@@ -35,7 +35,7 @@ class SerializerExtractor implements PropertyListExtractorInterface
      */
     public function getProperties($class, array $context = array())
     {
-        if (!isset($context['serializer_groups']) || !is_array($context['serializer_groups'])) {
+        if (!isset($context['serializer_groups']) || !\is_array($context['serializer_groups'])) {
             return;
         }
 
diff --git a/src/Symfony/Component/PropertyInfo/PropertyInfoCacheExtractor.php b/src/Symfony/Component/PropertyInfo/PropertyInfoCacheExtractor.php
index ecb6adde2a..90fd8a0fb8 100644
--- a/src/Symfony/Component/PropertyInfo/PropertyInfoCacheExtractor.php
+++ b/src/Symfony/Component/PropertyInfo/PropertyInfoCacheExtractor.php
@@ -91,7 +91,7 @@ class PropertyInfoCacheExtractor implements PropertyInfoExtractorInterface
             $serializedArguments = serialize($arguments);
         } catch (\Exception $exception) {
             // If arguments are not serializable, skip the cache
-            return call_user_func_array(array($this->propertyInfoExtractor, $method), $arguments);
+            return \call_user_func_array(array($this->propertyInfoExtractor, $method), $arguments);
         }
 
         // Calling rawurlencode escapes special characters not allowed in PSR-6's keys
@@ -107,7 +107,7 @@ class PropertyInfoCacheExtractor implements PropertyInfoExtractorInterface
             return $this->arrayCache[$key] = $item->get();
         }
 
-        $value = call_user_func_array(array($this->propertyInfoExtractor, $method), $arguments);
+        $value = \call_user_func_array(array($this->propertyInfoExtractor, $method), $arguments);
         $item->set($value);
         $this->cacheItemPool->save($item);
 
diff --git a/src/Symfony/Component/PropertyInfo/Tests/Fixtures/NullExtractor.php b/src/Symfony/Component/PropertyInfo/Tests/Fixtures/NullExtractor.php
index 4c2af41120..1f263bfc3c 100644
--- a/src/Symfony/Component/PropertyInfo/Tests/Fixtures/NullExtractor.php
+++ b/src/Symfony/Component/PropertyInfo/Tests/Fixtures/NullExtractor.php
@@ -78,8 +78,8 @@ class NullExtractor implements PropertyListExtractorInterface, PropertyDescripti
 
     private function assertIsString($string)
     {
-        if (!is_string($string)) {
-            throw new \InvalidArgumentException(sprintf('"%s" expects strings, given "%s".', __CLASS__, gettype($string)));
+        if (!\is_string($string)) {
+            throw new \InvalidArgumentException(sprintf('"%s" expects strings, given "%s".', __CLASS__, \gettype($string)));
         }
     }
 }
diff --git a/src/Symfony/Component/PropertyInfo/Type.php b/src/Symfony/Component/PropertyInfo/Type.php
index 461495ed51..1a33e29abd 100644
--- a/src/Symfony/Component/PropertyInfo/Type.php
+++ b/src/Symfony/Component/PropertyInfo/Type.php
@@ -61,7 +61,7 @@ class Type
      */
     public function __construct(string $builtinType, bool $nullable = false, string $class = null, bool $collection = false, self $collectionKeyType = null, self $collectionValueType = null)
     {
-        if (!in_array($builtinType, self::$builtinTypes)) {
+        if (!\in_array($builtinType, self::$builtinTypes)) {
             throw new \InvalidArgumentException(sprintf('"%s" is not a valid PHP type.', $builtinType));
         }
 
diff --git a/src/Symfony/Component/PropertyInfo/Util/PhpDocTypeHelper.php b/src/Symfony/Component/PropertyInfo/Util/PhpDocTypeHelper.php
index d8435471d7..048bd0f9dc 100644
--- a/src/Symfony/Component/PropertyInfo/Util/PhpDocTypeHelper.php
+++ b/src/Symfony/Component/PropertyInfo/Util/PhpDocTypeHelper.php
@@ -153,7 +153,7 @@ final class PhpDocTypeHelper
 
     private function getPhpTypeAndClass(string $docType): array
     {
-        if (in_array($docType, Type::$builtinTypes)) {
+        if (\in_array($docType, Type::$builtinTypes)) {
             return array($docType, null);
         }
 
diff --git a/src/Symfony/Component/Routing/Annotation/Route.php b/src/Symfony/Component/Routing/Annotation/Route.php
index 7924aa3458..62ad8c8b86 100644
--- a/src/Symfony/Component/Routing/Annotation/Route.php
+++ b/src/Symfony/Component/Routing/Annotation/Route.php
@@ -40,15 +40,15 @@ class Route
     public function __construct(array $data)
     {
         if (isset($data['localized_paths'])) {
-            throw new \BadMethodCallException(sprintf('Unknown property "localized_paths" on annotation "%s".', get_class($this)));
+            throw new \BadMethodCallException(sprintf('Unknown property "localized_paths" on annotation "%s".', \get_class($this)));
         }
 
         if (isset($data['value'])) {
-            $data[is_array($data['value']) ? 'localized_paths' : 'path'] = $data['value'];
+            $data[\is_array($data['value']) ? 'localized_paths' : 'path'] = $data['value'];
             unset($data['value']);
         }
 
-        if (isset($data['path']) && is_array($data['path'])) {
+        if (isset($data['path']) && \is_array($data['path'])) {
             $data['localized_paths'] = $data['path'];
             unset($data['path']);
         }
@@ -56,7 +56,7 @@ class Route
         foreach ($data as $key => $value) {
             $method = 'set'.str_replace('_', '', $key);
             if (!method_exists($this, $method)) {
-                throw new \BadMethodCallException(sprintf('Unknown property "%s" on annotation "%s".', $key, get_class($this)));
+                throw new \BadMethodCallException(sprintf('Unknown property "%s" on annotation "%s".', $key, \get_class($this)));
             }
             $this->$method($value);
         }
@@ -134,7 +134,7 @@ class Route
 
     public function setSchemes($schemes)
     {
-        $this->schemes = is_array($schemes) ? $schemes : array($schemes);
+        $this->schemes = \is_array($schemes) ? $schemes : array($schemes);
     }
 
     public function getSchemes()
@@ -144,7 +144,7 @@ class Route
 
     public function setMethods($methods)
     {
-        $this->methods = is_array($methods) ? $methods : array($methods);
+        $this->methods = \is_array($methods) ? $methods : array($methods);
     }
 
     public function getMethods()
diff --git a/src/Symfony/Component/Routing/Generator/UrlGenerator.php b/src/Symfony/Component/Routing/Generator/UrlGenerator.php
index 6bb8222266..b52bffe841 100644
--- a/src/Symfony/Component/Routing/Generator/UrlGenerator.php
+++ b/src/Symfony/Component/Routing/Generator/UrlGenerator.php
@@ -194,7 +194,7 @@ class UrlGenerator implements UrlGeneratorInterface, ConfigurableRequirementsInt
         $scheme = $this->context->getScheme();
 
         if ($requiredSchemes) {
-            if (!in_array($scheme, $requiredSchemes, true)) {
+            if (!\in_array($scheme, $requiredSchemes, true)) {
                 $referenceType = self::ABSOLUTE_URL;
                 $scheme = current($requiredSchemes);
             }
@@ -317,7 +317,7 @@ class UrlGenerator implements UrlGeneratorInterface, ConfigurableRequirementsInt
         }
 
         $targetDirs[] = $targetFile;
-        $path = str_repeat('../', count($sourceDirs)).implode('/', $targetDirs);
+        $path = str_repeat('../', \count($sourceDirs)).implode('/', $targetDirs);
 
         // A reference to the same base directory or an empty subdirectory must be prefixed with "./".
         // This also applies to a segment with a colon character (e.g., "file:colon") that cannot be used
diff --git a/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php b/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php
index 227f40ef42..2469c2da20 100644
--- a/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php
+++ b/src/Symfony/Component/Routing/Loader/AnnotationClassLoader.php
@@ -145,7 +145,7 @@ abstract class AnnotationClassLoader implements LoaderInterface
         $requirements = $annot->getRequirements();
 
         foreach ($requirements as $placeholder => $requirement) {
-            if (is_int($placeholder)) {
+            if (\is_int($placeholder)) {
                 @trigger_error(sprintf('A placeholder name must be a string (%d given). Did you forget to specify the placeholder key for the requirement "%s" of route "%s" in "%s::%s()"?', $placeholder, $requirement, $name, $class->getName(), $method->getName()), E_USER_DEPRECATED);
             }
         }
@@ -224,7 +224,7 @@ abstract class AnnotationClassLoader implements LoaderInterface
      */
     public function supports($resource, $type = null)
     {
-        return is_string($resource) && preg_match('/^(?:\\\\?[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)+$/', $resource) && (!$type || 'annotation' === $type);
+        return \is_string($resource) && preg_match('/^(?:\\\\?[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*)+$/', $resource) && (!$type || 'annotation' === $type);
     }
 
     /**
@@ -315,7 +315,7 @@ abstract class AnnotationClassLoader implements LoaderInterface
             }
 
             foreach ($globals['requirements'] as $placeholder => $requirement) {
-                if (is_int($placeholder)) {
+                if (\is_int($placeholder)) {
                     @trigger_error(sprintf('A placeholder name must be a string (%d given). Did you forget to specify the placeholder key for the requirement "%s" in "%s"?', $placeholder, $requirement, $class->getName()), E_USER_DEPRECATED);
                 }
             }
diff --git a/src/Symfony/Component/Routing/Loader/AnnotationDirectoryLoader.php b/src/Symfony/Component/Routing/Loader/AnnotationDirectoryLoader.php
index 4574a0201c..fd446435d4 100644
--- a/src/Symfony/Component/Routing/Loader/AnnotationDirectoryLoader.php
+++ b/src/Symfony/Component/Routing/Loader/AnnotationDirectoryLoader.php
@@ -80,7 +80,7 @@ class AnnotationDirectoryLoader extends AnnotationFileLoader
             return true;
         }
 
-        if ($type || !is_string($resource)) {
+        if ($type || !\is_string($resource)) {
             return false;
         }
 
diff --git a/src/Symfony/Component/Routing/Loader/AnnotationFileLoader.php b/src/Symfony/Component/Routing/Loader/AnnotationFileLoader.php
index b1cb104b58..4d51db2e3d 100644
--- a/src/Symfony/Component/Routing/Loader/AnnotationFileLoader.php
+++ b/src/Symfony/Component/Routing/Loader/AnnotationFileLoader.php
@@ -31,7 +31,7 @@ class AnnotationFileLoader extends FileLoader
      */
     public function __construct(FileLocatorInterface $locator, AnnotationClassLoader $loader)
     {
-        if (!function_exists('token_get_all')) {
+        if (!\function_exists('token_get_all')) {
             throw new \RuntimeException('The Tokenizer extension is required for the routing annotation loaders.');
         }
 
@@ -71,7 +71,7 @@ class AnnotationFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        return is_string($resource) && 'php' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'annotation' === $type);
+        return \is_string($resource) && 'php' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'annotation' === $type);
     }
 
     /**
@@ -87,7 +87,7 @@ class AnnotationFileLoader extends FileLoader
         $namespace = false;
         $tokens = token_get_all(file_get_contents($file));
 
-        if (1 === count($tokens) && T_INLINE_HTML === $tokens[0][0]) {
+        if (1 === \count($tokens) && T_INLINE_HTML === $tokens[0][0]) {
             throw new \InvalidArgumentException(sprintf('The file "%s" does not contain PHP code. Did you forgot to add the "<?php" start tag at the beginning of the file?', $file));
         }
 
@@ -104,7 +104,7 @@ class AnnotationFileLoader extends FileLoader
 
             if (true === $namespace && T_STRING === $token[0]) {
                 $namespace = $token[1];
-                while (isset($tokens[++$i][1]) && in_array($tokens[$i][0], array(T_NS_SEPARATOR, T_STRING))) {
+                while (isset($tokens[++$i][1]) && \in_array($tokens[$i][0], array(T_NS_SEPARATOR, T_STRING))) {
                     $namespace .= $tokens[$i][1];
                 }
                 $token = $tokens[$i];
@@ -121,7 +121,7 @@ class AnnotationFileLoader extends FileLoader
                     if (T_DOUBLE_COLON === $tokens[$j][0] || T_NEW === $tokens[$j][0]) {
                         $skipClassToken = true;
                         break;
-                    } elseif (!in_array($tokens[$j][0], array(T_WHITESPACE, T_DOC_COMMENT, T_COMMENT))) {
+                    } elseif (!\in_array($tokens[$j][0], array(T_WHITESPACE, T_DOC_COMMENT, T_COMMENT))) {
                         break;
                     }
                 }
diff --git a/src/Symfony/Component/Routing/Loader/Configurator/RoutingConfigurator.php b/src/Symfony/Component/Routing/Loader/Configurator/RoutingConfigurator.php
index 172fc9eef2..a315cfb4ad 100644
--- a/src/Symfony/Component/Routing/Loader/Configurator/RoutingConfigurator.php
+++ b/src/Symfony/Component/Routing/Loader/Configurator/RoutingConfigurator.php
@@ -38,9 +38,9 @@ class RoutingConfigurator
      */
     final public function import($resource, $type = null, $ignoreErrors = false)
     {
-        $this->loader->setCurrentDir(dirname($this->path));
+        $this->loader->setCurrentDir(\dirname($this->path));
         $imported = $this->loader->import($resource, $type, $ignoreErrors, $this->file);
-        if (!is_array($imported)) {
+        if (!\is_array($imported)) {
             return new ImportConfigurator($this->collection, $imported);
         }
 
diff --git a/src/Symfony/Component/Routing/Loader/ObjectRouteLoader.php b/src/Symfony/Component/Routing/Loader/ObjectRouteLoader.php
index 24925447df..dd14487ce0 100644
--- a/src/Symfony/Component/Routing/Loader/ObjectRouteLoader.php
+++ b/src/Symfony/Component/Routing/Loader/ObjectRouteLoader.php
@@ -50,7 +50,7 @@ abstract class ObjectRouteLoader extends Loader
         }
 
         $parts = explode('::', $resource);
-        if (2 != count($parts)) {
+        if (2 != \count($parts)) {
             throw new \InvalidArgumentException(sprintf('Invalid resource "%s" passed to the "service" route loader: use the format "service::method"', $resource));
         }
 
@@ -59,20 +59,20 @@ abstract class ObjectRouteLoader extends Loader
 
         $loaderObject = $this->getServiceObject($serviceString);
 
-        if (!is_object($loaderObject)) {
-            throw new \LogicException(sprintf('%s:getServiceObject() must return an object: %s returned', get_class($this), gettype($loaderObject)));
+        if (!\is_object($loaderObject)) {
+            throw new \LogicException(sprintf('%s:getServiceObject() must return an object: %s returned', \get_class($this), \gettype($loaderObject)));
         }
 
-        if (!is_callable(array($loaderObject, $method))) {
-            throw new \BadMethodCallException(sprintf('Method "%s" not found on "%s" when importing routing resource "%s"', $method, get_class($loaderObject), $resource));
+        if (!\is_callable(array($loaderObject, $method))) {
+            throw new \BadMethodCallException(sprintf('Method "%s" not found on "%s" when importing routing resource "%s"', $method, \get_class($loaderObject), $resource));
         }
 
-        $routeCollection = call_user_func(array($loaderObject, $method), $this);
+        $routeCollection = \call_user_func(array($loaderObject, $method), $this);
 
         if (!$routeCollection instanceof RouteCollection) {
-            $type = is_object($routeCollection) ? get_class($routeCollection) : gettype($routeCollection);
+            $type = \is_object($routeCollection) ? \get_class($routeCollection) : \gettype($routeCollection);
 
-            throw new \LogicException(sprintf('The %s::%s method must return a RouteCollection: %s returned', get_class($loaderObject), $method, $type));
+            throw new \LogicException(sprintf('The %s::%s method must return a RouteCollection: %s returned', \get_class($loaderObject), $method, $type));
         }
 
         // make the service file tracked so that if it changes, the cache rebuilds
diff --git a/src/Symfony/Component/Routing/Loader/PhpFileLoader.php b/src/Symfony/Component/Routing/Loader/PhpFileLoader.php
index 106ef5f62c..8d7b0cb3a3 100644
--- a/src/Symfony/Component/Routing/Loader/PhpFileLoader.php
+++ b/src/Symfony/Component/Routing/Loader/PhpFileLoader.php
@@ -36,7 +36,7 @@ class PhpFileLoader extends FileLoader
     public function load($file, $type = null)
     {
         $path = $this->locator->locate($file);
-        $this->setCurrentDir(dirname($path));
+        $this->setCurrentDir(\dirname($path));
 
         // the closure forbids access to the private scope in the included file
         $loader = $this;
@@ -63,7 +63,7 @@ class PhpFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        return is_string($resource) && 'php' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'php' === $type);
+        return \is_string($resource) && 'php' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'php' === $type);
     }
 }
 
diff --git a/src/Symfony/Component/Routing/Loader/XmlFileLoader.php b/src/Symfony/Component/Routing/Loader/XmlFileLoader.php
index f32c5ba23d..d1cad23bd3 100644
--- a/src/Symfony/Component/Routing/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/Routing/Loader/XmlFileLoader.php
@@ -93,7 +93,7 @@ class XmlFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        return is_string($resource) && 'xml' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'xml' === $type);
+        return \is_string($resource) && 'xml' === pathinfo($resource, PATHINFO_EXTENSION) && (!$type || 'xml' === $type);
     }
 
     /**
@@ -166,11 +166,11 @@ class XmlFileLoader extends FileLoader
             throw new \InvalidArgumentException(sprintf('The <route> element in file "%s" must not have both a "prefix" attribute and <prefix> child nodes.', $path));
         }
 
-        $this->setCurrentDir(dirname($path));
+        $this->setCurrentDir(\dirname($path));
 
         $imported = $this->import($resource, ('' !== $type ? $type : null), false, $file);
 
-        if (!is_array($imported)) {
+        if (!\is_array($imported)) {
             $imported = array($imported);
         }
 
diff --git a/src/Symfony/Component/Routing/Loader/YamlFileLoader.php b/src/Symfony/Component/Routing/Loader/YamlFileLoader.php
index 62b463b9b7..e47392ff9a 100644
--- a/src/Symfony/Component/Routing/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/Routing/Loader/YamlFileLoader.php
@@ -73,7 +73,7 @@ class YamlFileLoader extends FileLoader
         }
 
         // not an array
-        if (!is_array($parsedConfig)) {
+        if (!\is_array($parsedConfig)) {
             throw new \InvalidArgumentException(sprintf('The file "%s" must contain a YAML array.', $path));
         }
 
@@ -95,7 +95,7 @@ class YamlFileLoader extends FileLoader
      */
     public function supports($resource, $type = null)
     {
-        return is_string($resource) && in_array(pathinfo($resource, PATHINFO_EXTENSION), array('yml', 'yaml'), true) && (!$type || 'yaml' === $type);
+        return \is_string($resource) && \in_array(pathinfo($resource, PATHINFO_EXTENSION), array('yml', 'yaml'), true) && (!$type || 'yaml' === $type);
     }
 
     /**
@@ -117,7 +117,7 @@ class YamlFileLoader extends FileLoader
         $condition = isset($config['condition']) ? $config['condition'] : null;
 
         foreach ($requirements as $placeholder => $requirement) {
-            if (is_int($placeholder)) {
+            if (\is_int($placeholder)) {
                 @trigger_error(sprintf('A placeholder name must be a string (%d given). Did you forget to specify the placeholder key for the requirement "%s" of route "%s" in "%s"?', $placeholder, $requirement, $name, $path), E_USER_DEPRECATED);
             }
         }
@@ -126,7 +126,7 @@ class YamlFileLoader extends FileLoader
             $defaults['_controller'] = $config['controller'];
         }
 
-        if (is_array($config['path'])) {
+        if (\is_array($config['path'])) {
             $route = new Route('', $defaults, $requirements, $options, $host, $schemes, $methods, $condition);
 
             foreach ($config['path'] as $locale => $path) {
@@ -167,11 +167,11 @@ class YamlFileLoader extends FileLoader
             $defaults['_controller'] = $config['controller'];
         }
 
-        $this->setCurrentDir(dirname($path));
+        $this->setCurrentDir(\dirname($path));
 
         $imported = $this->import($config['resource'], $type, false, $file);
 
-        if (!is_array($imported)) {
+        if (!\is_array($imported)) {
             $imported = array($imported);
         }
 
@@ -246,7 +246,7 @@ class YamlFileLoader extends FileLoader
      */
     protected function validate($config, $name, $path)
     {
-        if (!is_array($config)) {
+        if (!\is_array($config)) {
             throw new \InvalidArgumentException(sprintf('The definition of "%s" in "%s" must be a YAML array.', $name, $path));
         }
         if ($extraKeys = array_diff(array_keys($config), self::$availableKeys)) {
diff --git a/src/Symfony/Component/Routing/Matcher/Dumper/PhpMatcherDumper.php b/src/Symfony/Component/Routing/Matcher/Dumper/PhpMatcherDumper.php
index c5af8c52a3..5cd1e6149e 100644
--- a/src/Symfony/Component/Routing/Matcher/Dumper/PhpMatcherDumper.php
+++ b/src/Symfony/Component/Routing/Matcher/Dumper/PhpMatcherDumper.php
@@ -177,7 +177,7 @@ EOF
         list($staticRoutes, $dynamicRoutes) = $this->groupStaticRoutes($routes);
 
         $code = $this->compileStaticRoutes($staticRoutes, $matchHost);
-        $chunkLimit = count($dynamicRoutes);
+        $chunkLimit = \count($dynamicRoutes);
 
         while (true) {
             try {
@@ -250,7 +250,7 @@ EOF
         $code = $default = '';
 
         foreach ($staticRoutes as $url => $routes) {
-            if (1 === count($routes)) {
+            if (1 === \count($routes)) {
                 foreach ($routes as $name => $route) {
                 }
 
@@ -368,7 +368,7 @@ EOF;
             $prev = false;
             $rx = '{^(?';
             $code .= "\n            {$state->mark} => ".self::export($rx);
-            $state->mark += strlen($rx);
+            $state->mark += \strlen($rx);
             $state->regex = $rx;
 
             foreach ($perHost as list($hostRegex, $routes)) {
@@ -382,7 +382,7 @@ EOF;
                         $hostRegex = '(?:(?:[^./]*+\.)++)';
                         $state->hostVars = array();
                     }
-                    $state->mark += strlen($rx = ($prev ? ')' : '')."|{$hostRegex}(?");
+                    $state->mark += \strlen($rx = ($prev ? ')' : '')."|{$hostRegex}(?");
                     $code .= "\n                .".self::export($rx);
                     $state->regex .= $rx;
                     $prev = true;
@@ -468,10 +468,10 @@ EOF;
             if ($route instanceof StaticPrefixCollection) {
                 $prevRegex = null;
                 $prefix = substr($route->getPrefix(), $prefixLen);
-                $state->mark += strlen($rx = "|{$prefix}(?");
+                $state->mark += \strlen($rx = "|{$prefix}(?");
                 $code .= "\n                    .".self::export($rx);
                 $state->regex .= $rx;
-                $code .= $this->indent($this->compileStaticPrefixCollection($route, $state, $prefixLen + strlen($prefix)));
+                $code .= $this->indent($this->compileStaticPrefixCollection($route, $state, $prefixLen + \strlen($prefix)));
                 $code .= "\n                    .')'";
                 $state->regex .= ')';
                 ++$state->markTail;
@@ -486,14 +486,14 @@ EOF;
                 continue;
             }
 
-            $state->mark += 3 + $state->markTail + strlen($regex) - $prefixLen;
-            $state->markTail = 2 + strlen($state->mark);
+            $state->mark += 3 + $state->markTail + \strlen($regex) - $prefixLen;
+            $state->markTail = 2 + \strlen($state->mark);
             $rx = sprintf('|%s(*:%s)', substr($regex, $prefixLen), $state->mark);
             $code .= "\n                    .".self::export($rx);
             $state->regex .= $rx;
             $vars = array_merge($state->hostVars, $vars);
 
-            if (!$route->getCondition() && (!is_array($next = $routes[1 + $i] ?? null) || $regex !== $next[1])) {
+            if (!$route->getCondition() && (!\is_array($next = $routes[1 + $i] ?? null) || $regex !== $next[1])) {
                 $prevRegex = null;
                 $defaults = $route->getDefaults();
                 if (isset($defaults['_canonical_route'])) {
@@ -628,7 +628,7 @@ EOF;
         $gotoname = 'not_'.preg_replace('/[^A-Za-z0-9_]/', '', $name);
 
         // the offset where the return value is appended below, with indendation
-        $retOffset = 12 + strlen($code);
+        $retOffset = 12 + \strlen($code);
         $defaults = $route->getDefaults();
         if (isset($defaults['_canonical_route'])) {
             $name = $defaults['_canonical_route'];
diff --git a/src/Symfony/Component/Routing/Matcher/TraceableUrlMatcher.php b/src/Symfony/Component/Routing/Matcher/TraceableUrlMatcher.php
index 9085be0424..61cad8e692 100644
--- a/src/Symfony/Component/Routing/Matcher/TraceableUrlMatcher.php
+++ b/src/Symfony/Component/Routing/Matcher/TraceableUrlMatcher.php
@@ -69,7 +69,7 @@ class TraceableUrlMatcher extends UrlMatcher
                     $r = new Route($route->getPath(), $route->getDefaults(), array($n => $regex), $route->getOptions());
                     $cr = $r->compile();
 
-                    if (in_array($n, $cr->getVariables()) && !preg_match($cr->getRegex(), $pathinfo)) {
+                    if (\in_array($n, $cr->getVariables()) && !preg_match($cr->getRegex(), $pathinfo)) {
                         $this->addTrace(sprintf('Requirement for "%s" does not match (%s)', $n, $regex), self::ROUTE_ALMOST_MATCHES, $name, $route);
 
                         continue 2;
@@ -94,7 +94,7 @@ class TraceableUrlMatcher extends UrlMatcher
                     $method = 'GET';
                 }
 
-                if (!in_array($method, $requiredMethods)) {
+                if (!\in_array($method, $requiredMethods)) {
                     $this->allow = array_merge($this->allow, $requiredMethods);
 
                     $this->addTrace(sprintf('Method "%s" does not match any of the required methods (%s)', $this->context->getMethod(), implode(', ', $requiredMethods)), self::ROUTE_ALMOST_MATCHES, $name, $route);
diff --git a/src/Symfony/Component/Routing/Matcher/UrlMatcher.php b/src/Symfony/Component/Routing/Matcher/UrlMatcher.php
index 95e2f19664..1909164e47 100644
--- a/src/Symfony/Component/Routing/Matcher/UrlMatcher.php
+++ b/src/Symfony/Component/Routing/Matcher/UrlMatcher.php
@@ -92,7 +92,7 @@ class UrlMatcher implements UrlMatcherInterface, RequestMatcherInterface
             throw new NoConfigurationException();
         }
 
-        throw 0 < count($this->allow)
+        throw 0 < \count($this->allow)
             ? new MethodNotAllowedException(array_unique($this->allow))
             : new ResourceNotFoundException(sprintf('No routes found for "%s".', $pathinfo));
     }
@@ -160,7 +160,7 @@ class UrlMatcher implements UrlMatcherInterface, RequestMatcherInterface
                     $method = 'GET';
                 }
 
-                if (!in_array($method, $requiredMethods)) {
+                if (!\in_array($method, $requiredMethods)) {
                     if ($hasRequiredScheme) {
                         $this->allow = array_merge($this->allow, $requiredMethods);
                     }
diff --git a/src/Symfony/Component/Routing/Route.php b/src/Symfony/Component/Routing/Route.php
index 09ac13de09..1b060a869d 100644
--- a/src/Symfony/Component/Routing/Route.php
+++ b/src/Symfony/Component/Routing/Route.php
@@ -209,7 +209,7 @@ class Route implements \Serializable
      */
     public function hasScheme($scheme)
     {
-        return in_array(strtolower($scheme), $this->schemes, true);
+        return \in_array(strtolower($scheme), $this->schemes, true);
     }
 
     /**
@@ -550,7 +550,7 @@ class Route implements \Serializable
 
     private function sanitizeRequirement($key, $regex)
     {
-        if (!is_string($regex)) {
+        if (!\is_string($regex)) {
             throw new \InvalidArgumentException(sprintf('Routing requirement for "%s" must be a string.', $key));
         }
 
diff --git a/src/Symfony/Component/Routing/RouteCollection.php b/src/Symfony/Component/Routing/RouteCollection.php
index 4d14ca96db..4525404d6d 100644
--- a/src/Symfony/Component/Routing/RouteCollection.php
+++ b/src/Symfony/Component/Routing/RouteCollection.php
@@ -63,7 +63,7 @@ class RouteCollection implements \IteratorAggregate, \Countable
      */
     public function count()
     {
-        return count($this->routes);
+        return \count($this->routes);
     }
 
     /**
diff --git a/src/Symfony/Component/Routing/RouteCollectionBuilder.php b/src/Symfony/Component/Routing/RouteCollectionBuilder.php
index c98d642a06..d5ff578c5d 100644
--- a/src/Symfony/Component/Routing/RouteCollectionBuilder.php
+++ b/src/Symfony/Component/Routing/RouteCollectionBuilder.php
@@ -358,7 +358,7 @@ class RouteCollectionBuilder
         if ($this->loader->supports($resource, $type)) {
             $collections = $this->loader->load($resource, $type);
 
-            return is_array($collections) ? $collections : array($collections);
+            return \is_array($collections) ? $collections : array($collections);
         }
 
         if (null === $resolver = $this->loader->getResolver()) {
@@ -371,6 +371,6 @@ class RouteCollectionBuilder
 
         $collections = $loader->load($resource, $type);
 
-        return is_array($collections) ? $collections : array($collections);
+        return \is_array($collections) ? $collections : array($collections);
     }
 }
diff --git a/src/Symfony/Component/Routing/RouteCompiler.php b/src/Symfony/Component/Routing/RouteCompiler.php
index 91b4a297cc..66b291b831 100644
--- a/src/Symfony/Component/Routing/RouteCompiler.php
+++ b/src/Symfony/Component/Routing/RouteCompiler.php
@@ -116,9 +116,9 @@ class RouteCompiler implements RouteCompilerInterface
             $varName = substr($match[0][0], 1, -1);
             // get all static text preceding the current variable
             $precedingText = substr($pattern, $pos, $match[0][1] - $pos);
-            $pos = $match[0][1] + strlen($match[0][0]);
+            $pos = $match[0][1] + \strlen($match[0][0]);
 
-            if (!strlen($precedingText)) {
+            if (!\strlen($precedingText)) {
                 $precedingChar = '';
             } elseif ($useUtf8) {
                 preg_match('/.$/u', $precedingText, $precedingChar);
@@ -133,17 +133,17 @@ class RouteCompiler implements RouteCompilerInterface
             if (preg_match('/^\d/', $varName)) {
                 throw new \DomainException(sprintf('Variable name "%s" cannot start with a digit in route pattern "%s". Please use a different name.', $varName, $pattern));
             }
-            if (in_array($varName, $variables)) {
+            if (\in_array($varName, $variables)) {
                 throw new \LogicException(sprintf('Route pattern "%s" cannot reference variable name "%s" more than once.', $pattern, $varName));
             }
 
-            if (strlen($varName) > self::VARIABLE_MAXIMUM_LENGTH) {
+            if (\strlen($varName) > self::VARIABLE_MAXIMUM_LENGTH) {
                 throw new \DomainException(sprintf('Variable name "%s" cannot be longer than %s characters in route pattern "%s". Please use a shorter name.', $varName, self::VARIABLE_MAXIMUM_LENGTH, $pattern));
             }
 
             if ($isSeparator && $precedingText !== $precedingChar) {
-                $tokens[] = array('text', substr($precedingText, 0, -strlen($precedingChar)));
-            } elseif (!$isSeparator && strlen($precedingText) > 0) {
+                $tokens[] = array('text', substr($precedingText, 0, -\strlen($precedingChar)));
+            } elseif (!$isSeparator && \strlen($precedingText) > 0) {
                 $tokens[] = array('text', $precedingText);
             }
 
@@ -187,14 +187,14 @@ class RouteCompiler implements RouteCompilerInterface
             $variables[] = $varName;
         }
 
-        if ($pos < strlen($pattern)) {
+        if ($pos < \strlen($pattern)) {
             $tokens[] = array('text', substr($pattern, $pos));
         }
 
         // find the first optional token
         $firstOptional = PHP_INT_MAX;
         if (!$isHost) {
-            for ($i = count($tokens) - 1; $i >= 0; --$i) {
+            for ($i = \count($tokens) - 1; $i >= 0; --$i) {
                 $token = $tokens[$i];
                 if ('variable' === $token[0] && $route->hasDefault($token[3])) {
                     $firstOptional = $i;
@@ -206,7 +206,7 @@ class RouteCompiler implements RouteCompilerInterface
 
         // compute the matching regexp
         $regexp = '';
-        for ($i = 0, $nbToken = count($tokens); $i < $nbToken; ++$i) {
+        for ($i = 0, $nbToken = \count($tokens); $i < $nbToken; ++$i) {
             $regexp .= self::computeRegexp($tokens, $i, $firstOptional);
         }
         $regexp = self::REGEX_DELIMITER.'^'.$regexp.'$'.self::REGEX_DELIMITER.'sD'.($isHost ? 'i' : '');
@@ -214,7 +214,7 @@ class RouteCompiler implements RouteCompilerInterface
         // enable Utf8 matching if really required
         if ($needsUtf8) {
             $regexp .= 'u';
-            for ($i = 0, $nbToken = count($tokens); $i < $nbToken; ++$i) {
+            for ($i = 0, $nbToken = \count($tokens); $i < $nbToken; ++$i) {
                 if ('variable' === $tokens[$i][0]) {
                     $tokens[$i][] = true;
                 }
@@ -294,7 +294,7 @@ class RouteCompiler implements RouteCompilerInterface
                     // "?:" means it is non-capturing, i.e. the portion of the subject string that
                     // matched the optional subpattern is not passed back.
                     $regexp = "(?:$regexp";
-                    $nbTokens = count($tokens);
+                    $nbTokens = \count($tokens);
                     if ($nbTokens - 1 == $index) {
                         // Close the optional subpatterns
                         $regexp .= str_repeat(')?', $nbTokens - $firstOptional - (0 === $firstOptional ? 1 : 0));
diff --git a/src/Symfony/Component/Routing/Tests/Loader/AnnotationDirectoryLoaderTest.php b/src/Symfony/Component/Routing/Tests/Loader/AnnotationDirectoryLoaderTest.php
index 8a6668e0c2..e85755ca7b 100644
--- a/src/Symfony/Component/Routing/Tests/Loader/AnnotationDirectoryLoaderTest.php
+++ b/src/Symfony/Component/Routing/Tests/Loader/AnnotationDirectoryLoaderTest.php
@@ -100,10 +100,10 @@ class AnnotationDirectoryLoaderTest extends AbstractAnnotationLoaderTest
 
     private function expectAnnotationsToBeReadFrom(array $classes)
     {
-        $this->reader->expects($this->exactly(count($classes)))
+        $this->reader->expects($this->exactly(\count($classes)))
             ->method('getClassAnnotation')
             ->with($this->callback(function (\ReflectionClass $class) use ($classes) {
-                return in_array($class->getName(), $classes);
+                return \in_array($class->getName(), $classes);
             }));
     }
 }
diff --git a/src/Symfony/Component/Security/Core/Authentication/AuthenticationProviderManager.php b/src/Symfony/Component/Security/Core/Authentication/AuthenticationProviderManager.php
index 3a86aecd09..7097fbf426 100644
--- a/src/Symfony/Component/Security/Core/Authentication/AuthenticationProviderManager.php
+++ b/src/Symfony/Component/Security/Core/Authentication/AuthenticationProviderManager.php
@@ -65,7 +65,7 @@ class AuthenticationProviderManager implements AuthenticationManagerInterface
 
         foreach ($this->providers as $provider) {
             if (!$provider instanceof AuthenticationProviderInterface) {
-                throw new \InvalidArgumentException(sprintf('Provider "%s" must implement the AuthenticationProviderInterface.', get_class($provider)));
+                throw new \InvalidArgumentException(sprintf('Provider "%s" must implement the AuthenticationProviderInterface.', \get_class($provider)));
             }
 
             if (!$provider->supports($token)) {
@@ -100,7 +100,7 @@ class AuthenticationProviderManager implements AuthenticationManagerInterface
         }
 
         if (null === $lastException) {
-            $lastException = new ProviderNotFoundException(sprintf('No Authentication Provider found for token of class "%s".', get_class($token)));
+            $lastException = new ProviderNotFoundException(sprintf('No Authentication Provider found for token of class "%s".', \get_class($token)));
         }
 
         if (null !== $this->eventDispatcher) {
diff --git a/src/Symfony/Component/Security/Core/Authentication/Token/AbstractToken.php b/src/Symfony/Component/Security/Core/Authentication/Token/AbstractToken.php
index 491c62bcc4..0f8f903fb7 100644
--- a/src/Symfony/Component/Security/Core/Authentication/Token/AbstractToken.php
+++ b/src/Symfony/Component/Security/Core/Authentication/Token/AbstractToken.php
@@ -37,10 +37,10 @@ abstract class AbstractToken implements TokenInterface
     public function __construct(array $roles = array())
     {
         foreach ($roles as $role) {
-            if (is_string($role)) {
+            if (\is_string($role)) {
                 $role = new Role($role);
             } elseif (!$role instanceof Role) {
-                throw new \InvalidArgumentException(sprintf('$roles must be an array of strings, or Role instances, but got %s.', gettype($role)));
+                throw new \InvalidArgumentException(sprintf('$roles must be an array of strings, or Role instances, but got %s.', \gettype($role)));
             }
 
             $this->roles[] = $role;
@@ -80,7 +80,7 @@ abstract class AbstractToken implements TokenInterface
      */
     public function setUser($user)
     {
-        if (!($user instanceof UserInterface || (is_object($user) && method_exists($user, '__toString')) || is_string($user))) {
+        if (!($user instanceof UserInterface || (\is_object($user) && method_exists($user, '__toString')) || \is_string($user))) {
             throw new \InvalidArgumentException('$user must be an instanceof UserInterface, an object implementing a __toString method, or a primitive string.');
         }
 
@@ -138,7 +138,7 @@ abstract class AbstractToken implements TokenInterface
     {
         return serialize(
             array(
-                is_object($this->user) ? clone $this->user : $this->user,
+                \is_object($this->user) ? clone $this->user : $this->user,
                 $this->authenticated,
                 array_map(function ($role) { return clone $role; }, $this->roles),
                 $this->attributes,
@@ -220,7 +220,7 @@ abstract class AbstractToken implements TokenInterface
      */
     public function __toString()
     {
-        $class = get_class($this);
+        $class = \get_class($this);
         $class = substr($class, strrpos($class, '\\') + 1);
 
         $roles = array();
diff --git a/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php b/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php
index 1959a1bdf9..fb1cdf8002 100644
--- a/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php
+++ b/src/Symfony/Component/Security/Core/Authentication/Token/UsernamePasswordToken.php
@@ -43,7 +43,7 @@ class UsernamePasswordToken extends AbstractToken
         $this->credentials = $credentials;
         $this->providerKey = $providerKey;
 
-        parent::setAuthenticated(count($roles) > 0);
+        parent::setAuthenticated(\count($roles) > 0);
     }
 
     /**
diff --git a/src/Symfony/Component/Security/Core/Authorization/AccessDecisionManager.php b/src/Symfony/Component/Security/Core/Authorization/AccessDecisionManager.php
index 3259bdd916..2f01807d0a 100644
--- a/src/Symfony/Component/Security/Core/Authorization/AccessDecisionManager.php
+++ b/src/Symfony/Component/Security/Core/Authorization/AccessDecisionManager.php
@@ -42,7 +42,7 @@ class AccessDecisionManager implements AccessDecisionManagerInterface
     public function __construct(iterable $voters = array(), string $strategy = self::STRATEGY_AFFIRMATIVE, bool $allowIfAllAbstainDecisions = false, bool $allowIfEqualGrantedDeniedDecisions = true)
     {
         $strategyMethod = 'decide'.ucfirst($strategy);
-        if (!is_callable(array($this, $strategyMethod))) {
+        if (!\is_callable(array($this, $strategyMethod))) {
             throw new \InvalidArgumentException(sprintf('The strategy "%s" is not supported.', $strategy));
         }
 
diff --git a/src/Symfony/Component/Security/Core/Authorization/AuthorizationChecker.php b/src/Symfony/Component/Security/Core/Authorization/AuthorizationChecker.php
index 67d5f833af..67c6de34b9 100644
--- a/src/Symfony/Component/Security/Core/Authorization/AuthorizationChecker.php
+++ b/src/Symfony/Component/Security/Core/Authorization/AuthorizationChecker.php
@@ -53,7 +53,7 @@ class AuthorizationChecker implements AuthorizationCheckerInterface
             $this->tokenStorage->setToken($token = $this->authenticationManager->authenticate($token));
         }
 
-        if (!is_array($attributes)) {
+        if (!\is_array($attributes)) {
             $attributes = array($attributes);
         }
 
diff --git a/src/Symfony/Component/Security/Core/Authorization/ExpressionLanguageProvider.php b/src/Symfony/Component/Security/Core/Authorization/ExpressionLanguageProvider.php
index 9e55111583..986c23e2ab 100644
--- a/src/Symfony/Component/Security/Core/Authorization/ExpressionLanguageProvider.php
+++ b/src/Symfony/Component/Security/Core/Authorization/ExpressionLanguageProvider.php
@@ -61,7 +61,7 @@ class ExpressionLanguageProvider implements ExpressionFunctionProviderInterface
             }, function (array $variables, $role) {
                 @trigger_error('Using the "has_role()" function in security expressions is deprecated since Symfony 4.2, use "is_granted()" instead.', E_USER_DEPRECATED);
 
-                return in_array($role, $variables['roles']);
+                return \in_array($role, $variables['roles']);
             }),
         );
     }
diff --git a/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php b/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php
index 63302c06bb..7eb9a61fe0 100644
--- a/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php
+++ b/src/Symfony/Component/Security/Core/Authorization/Voter/ExpressionVoter.php
@@ -44,7 +44,7 @@ class ExpressionVoter implements VoterInterface
         } elseif (null === $authChecker) {
             @trigger_error(sprintf('Argument 3 passed to "%s()" should be an instance of AuthorizationCheckerInterface, not passing it is deprecated since Symfony 4.2.', __METHOD__), E_USER_DEPRECATED);
         } elseif (!$authChecker instanceof AuthorizationCheckerInterface) {
-            throw new \InvalidArgumentException(sprintf('Argument 3 passed to %s() must be an instance of %s or null, %s given.', __METHOD__, AuthorizationCheckerInterface::class, is_object($authChecker) ? get_class($authChecker) : gettype($authChecker)));
+            throw new \InvalidArgumentException(sprintf('Argument 3 passed to %s() must be an instance of %s or null, %s given.', __METHOD__, AuthorizationCheckerInterface::class, \is_object($authChecker) ? \get_class($authChecker) : \gettype($authChecker)));
         }
 
         $this->expressionLanguage = $expressionLanguage;
diff --git a/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php b/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php
index 3742b9912f..fc2e6883e4 100644
--- a/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php
+++ b/src/Symfony/Component/Security/Core/Authorization/Voter/RoleVoter.php
@@ -41,7 +41,7 @@ class RoleVoter implements VoterInterface
                 $attribute = $attribute->getRole();
             }
 
-            if (!is_string($attribute) || 0 !== strpos($attribute, $this->prefix)) {
+            if (!\is_string($attribute) || 0 !== strpos($attribute, $this->prefix)) {
                 continue;
             }
 
diff --git a/src/Symfony/Component/Security/Core/Encoder/BasePasswordEncoder.php b/src/Symfony/Component/Security/Core/Encoder/BasePasswordEncoder.php
index 57daa66557..75c4db896f 100644
--- a/src/Symfony/Component/Security/Core/Encoder/BasePasswordEncoder.php
+++ b/src/Symfony/Component/Security/Core/Encoder/BasePasswordEncoder.php
@@ -37,7 +37,7 @@ abstract class BasePasswordEncoder implements PasswordEncoderInterface
         $salt = '';
         $saltBegins = strrpos($mergedPasswordSalt, '{');
 
-        if (false !== $saltBegins && $saltBegins + 1 < strlen($mergedPasswordSalt)) {
+        if (false !== $saltBegins && $saltBegins + 1 < \strlen($mergedPasswordSalt)) {
             $salt = substr($mergedPasswordSalt, $saltBegins + 1, -1);
             $password = substr($mergedPasswordSalt, 0, $saltBegins);
         }
@@ -93,6 +93,6 @@ abstract class BasePasswordEncoder implements PasswordEncoderInterface
      */
     protected function isPasswordTooLong($password)
     {
-        return strlen($password) > static::MAX_PASSWORD_LENGTH;
+        return \strlen($password) > static::MAX_PASSWORD_LENGTH;
     }
 }
diff --git a/src/Symfony/Component/Security/Core/Encoder/EncoderFactory.php b/src/Symfony/Component/Security/Core/Encoder/EncoderFactory.php
index e65c30feaa..4885b792ba 100644
--- a/src/Symfony/Component/Security/Core/Encoder/EncoderFactory.php
+++ b/src/Symfony/Component/Security/Core/Encoder/EncoderFactory.php
@@ -40,7 +40,7 @@ class EncoderFactory implements EncoderFactoryInterface
             $encoderKey = $encoderName;
         } else {
             foreach ($this->encoders as $class => $encoder) {
-                if ((is_object($user) && $user instanceof $class) || (!is_object($user) && (is_subclass_of($user, $class) || $user == $class))) {
+                if ((\is_object($user) && $user instanceof $class) || (!\is_object($user) && (is_subclass_of($user, $class) || $user == $class))) {
                     $encoderKey = $class;
                     break;
                 }
@@ -48,7 +48,7 @@ class EncoderFactory implements EncoderFactoryInterface
         }
 
         if (null === $encoderKey) {
-            throw new \RuntimeException(sprintf('No encoder has been configured for account "%s".', is_object($user) ? get_class($user) : $user));
+            throw new \RuntimeException(sprintf('No encoder has been configured for account "%s".', \is_object($user) ? \get_class($user) : $user));
         }
 
         if (!$this->encoders[$encoderKey] instanceof PasswordEncoderInterface) {
diff --git a/src/Symfony/Component/Security/Core/Encoder/MessageDigestPasswordEncoder.php b/src/Symfony/Component/Security/Core/Encoder/MessageDigestPasswordEncoder.php
index b960580f20..dba0c30d5a 100644
--- a/src/Symfony/Component/Security/Core/Encoder/MessageDigestPasswordEncoder.php
+++ b/src/Symfony/Component/Security/Core/Encoder/MessageDigestPasswordEncoder.php
@@ -45,7 +45,7 @@ class MessageDigestPasswordEncoder extends BasePasswordEncoder
             throw new BadCredentialsException('Invalid password.');
         }
 
-        if (!in_array($this->algorithm, hash_algos(), true)) {
+        if (!\in_array($this->algorithm, hash_algos(), true)) {
             throw new \LogicException(sprintf('The algorithm "%s" is not supported.', $this->algorithm));
         }
 
diff --git a/src/Symfony/Component/Security/Core/Encoder/Pbkdf2PasswordEncoder.php b/src/Symfony/Component/Security/Core/Encoder/Pbkdf2PasswordEncoder.php
index 186ee698bf..4c4eee75d8 100644
--- a/src/Symfony/Component/Security/Core/Encoder/Pbkdf2PasswordEncoder.php
+++ b/src/Symfony/Component/Security/Core/Encoder/Pbkdf2PasswordEncoder.php
@@ -58,7 +58,7 @@ class Pbkdf2PasswordEncoder extends BasePasswordEncoder
             throw new BadCredentialsException('Invalid password.');
         }
 
-        if (!in_array($this->algorithm, hash_algos(), true)) {
+        if (!\in_array($this->algorithm, hash_algos(), true)) {
             throw new \LogicException(sprintf('The algorithm "%s" is not supported.', $this->algorithm));
         }
 
diff --git a/src/Symfony/Component/Security/Core/Security.php b/src/Symfony/Component/Security/Core/Security.php
index 1cb3056d1e..eac0e958a9 100644
--- a/src/Symfony/Component/Security/Core/Security.php
+++ b/src/Symfony/Component/Security/Core/Security.php
@@ -42,12 +42,12 @@ final class Security
         }
 
         $user = $token->getUser();
-        if (!is_object($user)) {
+        if (!\is_object($user)) {
             return null;
         }
 
         if (!$user instanceof UserInterface) {
-            @trigger_error(sprintf('Accessing the user object "%s" that is not an instance of "%s" from "%s()" is deprecated since Symfony 4.2, use "getToken()->getUser()" instead.', get_class($user), UserInterface::class, __METHOD__), E_USER_DEPRECATED);
+            @trigger_error(sprintf('Accessing the user object "%s" that is not an instance of "%s" from "%s()" is deprecated since Symfony 4.2, use "getToken()->getUser()" instead.', \get_class($user), UserInterface::class, __METHOD__), E_USER_DEPRECATED);
             //return null; // 5.0 behavior
         }
 
diff --git a/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/VoterTest.php b/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/VoterTest.php
index 70e3226ece..f0e10cde1a 100644
--- a/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/VoterTest.php
+++ b/src/Symfony/Component/Security/Core/Tests/Authorization/Voter/VoterTest.php
@@ -66,6 +66,6 @@ class VoterTest_Voter extends Voter
 
     protected function supports($attribute, $object)
     {
-        return $object instanceof \stdClass && in_array($attribute, array('EDIT', 'CREATE'));
+        return $object instanceof \stdClass && \in_array($attribute, array('EDIT', 'CREATE'));
     }
 }
diff --git a/src/Symfony/Component/Security/Core/Tests/Encoder/BCryptPasswordEncoderTest.php b/src/Symfony/Component/Security/Core/Tests/Encoder/BCryptPasswordEncoderTest.php
index 0977d73507..55590ffc3d 100644
--- a/src/Symfony/Component/Security/Core/Tests/Encoder/BCryptPasswordEncoderTest.php
+++ b/src/Symfony/Component/Security/Core/Tests/Encoder/BCryptPasswordEncoderTest.php
@@ -58,7 +58,7 @@ class BCryptPasswordEncoderTest extends TestCase
     {
         $encoder = new BCryptPasswordEncoder(self::VALID_COST);
         $result = $encoder->encodePassword(self::PASSWORD, null);
-        $this->assertEquals(60, strlen($result));
+        $this->assertEquals(60, \strlen($result));
     }
 
     public function testValidation()
diff --git a/src/Symfony/Component/Security/Core/Tests/Resources/TranslationFilesTest.php b/src/Symfony/Component/Security/Core/Tests/Resources/TranslationFilesTest.php
index 07c5e304b4..f4e0d9e6e8 100644
--- a/src/Symfony/Component/Security/Core/Tests/Resources/TranslationFilesTest.php
+++ b/src/Symfony/Component/Security/Core/Tests/Resources/TranslationFilesTest.php
@@ -33,15 +33,15 @@ class TranslationFilesTest extends TestCase
     {
         return array_map(
             function ($filePath) { return (array) $filePath; },
-            glob(dirname(dirname(__DIR__)).'/Resources/translations/*.xlf')
+            glob(\dirname(\dirname(__DIR__)).'/Resources/translations/*.xlf')
         );
     }
 
     public function testNorwegianAlias()
     {
         $this->assertFileEquals(
-            dirname(dirname(__DIR__)).'/Resources/translations/security.nb.xlf',
-            dirname(dirname(__DIR__)).'/Resources/translations/security.no.xlf',
+            \dirname(\dirname(__DIR__)).'/Resources/translations/security.nb.xlf',
+            \dirname(\dirname(__DIR__)).'/Resources/translations/security.no.xlf',
             'The NO locale should be an alias for the NB variant of the Norwegian language.'
         );
     }
diff --git a/src/Symfony/Component/Security/Core/User/ChainUserProvider.php b/src/Symfony/Component/Security/Core/User/ChainUserProvider.php
index 1faa723990..4106ad190a 100644
--- a/src/Symfony/Component/Security/Core/User/ChainUserProvider.php
+++ b/src/Symfony/Component/Security/Core/User/ChainUserProvider.php
@@ -87,7 +87,7 @@ class ChainUserProvider implements UserProviderInterface
             $e->setUsername($user->getUsername());
             throw $e;
         } else {
-            throw new UnsupportedUserException(sprintf('The account "%s" is not supported.', get_class($user)));
+            throw new UnsupportedUserException(sprintf('The account "%s" is not supported.', \get_class($user)));
         }
     }
 
diff --git a/src/Symfony/Component/Security/Core/User/InMemoryUserProvider.php b/src/Symfony/Component/Security/Core/User/InMemoryUserProvider.php
index 0af14e6a46..7c2c3d415e 100644
--- a/src/Symfony/Component/Security/Core/User/InMemoryUserProvider.php
+++ b/src/Symfony/Component/Security/Core/User/InMemoryUserProvider.php
@@ -74,7 +74,7 @@ class InMemoryUserProvider implements UserProviderInterface
     public function refreshUser(UserInterface $user)
     {
         if (!$user instanceof User) {
-            throw new UnsupportedUserException(sprintf('Instances of "%s" are not supported.', get_class($user)));
+            throw new UnsupportedUserException(sprintf('Instances of "%s" are not supported.', \get_class($user)));
         }
 
         $storedUser = $this->getUser($user->getUsername());
diff --git a/src/Symfony/Component/Security/Core/User/LdapUserProvider.php b/src/Symfony/Component/Security/Core/User/LdapUserProvider.php
index 7dd9b71b9e..8ef874260c 100644
--- a/src/Symfony/Component/Security/Core/User/LdapUserProvider.php
+++ b/src/Symfony/Component/Security/Core/User/LdapUserProvider.php
@@ -70,7 +70,7 @@ class LdapUserProvider implements UserProviderInterface
         }
 
         $entries = $search->execute();
-        $count = count($entries);
+        $count = \count($entries);
 
         if (!$count) {
             throw new UsernameNotFoundException(sprintf('User "%s" not found.', $username));
@@ -98,7 +98,7 @@ class LdapUserProvider implements UserProviderInterface
     public function refreshUser(UserInterface $user)
     {
         if (!$user instanceof User) {
-            throw new UnsupportedUserException(sprintf('Instances of "%s" are not supported.', get_class($user)));
+            throw new UnsupportedUserException(sprintf('Instances of "%s" are not supported.', \get_class($user)));
         }
 
         return new User($user->getUsername(), null, $user->getRoles());
@@ -145,7 +145,7 @@ class LdapUserProvider implements UserProviderInterface
 
         $values = $entry->getAttribute($attribute);
 
-        if (1 !== count($values)) {
+        if (1 !== \count($values)) {
             throw new InvalidArgumentException(sprintf('Attribute "%s" has multiple values.', $attribute));
         }
 
diff --git a/src/Symfony/Component/Security/Csrf/CsrfTokenManager.php b/src/Symfony/Component/Security/Csrf/CsrfTokenManager.php
index 332880fda5..c19126eaf6 100644
--- a/src/Symfony/Component/Security/Csrf/CsrfTokenManager.php
+++ b/src/Symfony/Component/Security/Csrf/CsrfTokenManager.php
@@ -56,10 +56,10 @@ class CsrfTokenManager implements CsrfTokenManagerInterface
 
                 return $superGlobalNamespaceGenerator();
             };
-        } elseif (is_callable($namespace) || is_string($namespace)) {
+        } elseif (\is_callable($namespace) || \is_string($namespace)) {
             $this->namespace = $namespace;
         } else {
-            throw new InvalidArgumentException(sprintf('$namespace must be a string, a callable returning a string, null or an instance of "RequestStack". "%s" given.', gettype($namespace)));
+            throw new InvalidArgumentException(sprintf('$namespace must be a string, a callable returning a string, null or an instance of "RequestStack". "%s" given.', \gettype($namespace)));
         }
     }
 
@@ -116,6 +116,6 @@ class CsrfTokenManager implements CsrfTokenManagerInterface
 
     private function getNamespace()
     {
-        return is_callable($ns = $this->namespace) ? $ns() : $ns;
+        return \is_callable($ns = $this->namespace) ? $ns() : $ns;
     }
 }
diff --git a/src/Symfony/Component/Security/Guard/Firewall/GuardAuthenticationListener.php b/src/Symfony/Component/Security/Guard/Firewall/GuardAuthenticationListener.php
index 67861de34b..b677da5b7a 100644
--- a/src/Symfony/Component/Security/Guard/Firewall/GuardAuthenticationListener.php
+++ b/src/Symfony/Component/Security/Guard/Firewall/GuardAuthenticationListener.php
@@ -67,8 +67,8 @@ class GuardAuthenticationListener implements ListenerInterface
         if (null !== $this->logger) {
             $context = array('firewall_key' => $this->providerKey);
 
-            if ($this->guardAuthenticators instanceof \Countable || is_array($this->guardAuthenticators)) {
-                $context['authenticators'] = count($this->guardAuthenticators);
+            if ($this->guardAuthenticators instanceof \Countable || \is_array($this->guardAuthenticators)) {
+                $context['authenticators'] = \count($this->guardAuthenticators);
             }
 
             $this->logger->debug('Checking for guard authentication credentials.', $context);
@@ -83,7 +83,7 @@ class GuardAuthenticationListener implements ListenerInterface
 
             if ($event->hasResponse()) {
                 if (null !== $this->logger) {
-                    $this->logger->debug('The "{authenticator}" authenticator set the response. Any later authenticator will not be called', array('authenticator' => get_class($guardAuthenticator)));
+                    $this->logger->debug('The "{authenticator}" authenticator set the response. Any later authenticator will not be called', array('authenticator' => \get_class($guardAuthenticator)));
                 }
 
                 break;
@@ -96,7 +96,7 @@ class GuardAuthenticationListener implements ListenerInterface
         $request = $event->getRequest();
         try {
             if (null !== $this->logger) {
-                $this->logger->debug('Calling getCredentials() on guard configurator.', array('firewall_key' => $this->providerKey, 'authenticator' => get_class($guardAuthenticator)));
+                $this->logger->debug('Calling getCredentials() on guard configurator.', array('firewall_key' => $this->providerKey, 'authenticator' => \get_class($guardAuthenticator)));
             }
 
             // abort the execution of the authenticator if it doesn't support the request
@@ -108,21 +108,21 @@ class GuardAuthenticationListener implements ListenerInterface
             $credentials = $guardAuthenticator->getCredentials($request);
 
             if (null === $credentials) {
-                throw new \UnexpectedValueException(sprintf('The return value of "%1$s::getCredentials()" must not be null. Return false from "%1$s::supports()" instead.', get_class($guardAuthenticator)));
+                throw new \UnexpectedValueException(sprintf('The return value of "%1$s::getCredentials()" must not be null. Return false from "%1$s::supports()" instead.', \get_class($guardAuthenticator)));
             }
 
             // create a token with the unique key, so that the provider knows which authenticator to use
             $token = new PreAuthenticationGuardToken($credentials, $uniqueGuardKey);
 
             if (null !== $this->logger) {
-                $this->logger->debug('Passing guard token information to the GuardAuthenticationProvider', array('firewall_key' => $this->providerKey, 'authenticator' => get_class($guardAuthenticator)));
+                $this->logger->debug('Passing guard token information to the GuardAuthenticationProvider', array('firewall_key' => $this->providerKey, 'authenticator' => \get_class($guardAuthenticator)));
             }
             // pass the token into the AuthenticationManager system
             // this indirectly calls GuardAuthenticationProvider::authenticate()
             $token = $this->authenticationManager->authenticate($token);
 
             if (null !== $this->logger) {
-                $this->logger->info('Guard authentication successful!', array('token' => $token, 'authenticator' => get_class($guardAuthenticator)));
+                $this->logger->info('Guard authentication successful!', array('token' => $token, 'authenticator' => \get_class($guardAuthenticator)));
             }
 
             // sets the token on the token storage, etc
@@ -131,7 +131,7 @@ class GuardAuthenticationListener implements ListenerInterface
             // oh no! Authentication failed!
 
             if (null !== $this->logger) {
-                $this->logger->info('Guard authentication failed.', array('exception' => $e, 'authenticator' => get_class($guardAuthenticator)));
+                $this->logger->info('Guard authentication failed.', array('exception' => $e, 'authenticator' => \get_class($guardAuthenticator)));
             }
 
             $response = $this->guardHandler->handleAuthenticationFailure($e, $request, $guardAuthenticator, $this->providerKey);
@@ -147,13 +147,13 @@ class GuardAuthenticationListener implements ListenerInterface
         $response = $this->guardHandler->handleAuthenticationSuccess($token, $request, $guardAuthenticator, $this->providerKey);
         if ($response instanceof Response) {
             if (null !== $this->logger) {
-                $this->logger->debug('Guard authenticator set success response.', array('response' => $response, 'authenticator' => get_class($guardAuthenticator)));
+                $this->logger->debug('Guard authenticator set success response.', array('response' => $response, 'authenticator' => \get_class($guardAuthenticator)));
             }
 
             $event->setResponse($response);
         } else {
             if (null !== $this->logger) {
-                $this->logger->debug('Guard authenticator set no success response: request continues.', array('authenticator' => get_class($guardAuthenticator)));
+                $this->logger->debug('Guard authenticator set no success response: request continues.', array('authenticator' => \get_class($guardAuthenticator)));
             }
         }
 
@@ -177,7 +177,7 @@ class GuardAuthenticationListener implements ListenerInterface
     {
         if (null === $this->rememberMeServices) {
             if (null !== $this->logger) {
-                $this->logger->debug('Remember me skipped: it is not configured for the firewall.', array('authenticator' => get_class($guardAuthenticator)));
+                $this->logger->debug('Remember me skipped: it is not configured for the firewall.', array('authenticator' => \get_class($guardAuthenticator)));
             }
 
             return;
@@ -185,7 +185,7 @@ class GuardAuthenticationListener implements ListenerInterface
 
         if (!$guardAuthenticator->supportsRememberMe()) {
             if (null !== $this->logger) {
-                $this->logger->debug('Remember me skipped: your authenticator does not support it.', array('authenticator' => get_class($guardAuthenticator)));
+                $this->logger->debug('Remember me skipped: your authenticator does not support it.', array('authenticator' => \get_class($guardAuthenticator)));
             }
 
             return;
@@ -194,7 +194,7 @@ class GuardAuthenticationListener implements ListenerInterface
         if (!$response instanceof Response) {
             throw new \LogicException(sprintf(
                 '%s::onAuthenticationSuccess *must* return a Response if you want to use the remember me functionality. Return a Response, or set remember_me to false under the guard configuration.',
-                get_class($guardAuthenticator)
+                \get_class($guardAuthenticator)
             ));
         }
 
diff --git a/src/Symfony/Component/Security/Guard/GuardAuthenticatorHandler.php b/src/Symfony/Component/Security/Guard/GuardAuthenticatorHandler.php
index 8084419207..aedbb65597 100644
--- a/src/Symfony/Component/Security/Guard/GuardAuthenticatorHandler.php
+++ b/src/Symfony/Component/Security/Guard/GuardAuthenticatorHandler.php
@@ -81,8 +81,8 @@ class GuardAuthenticatorHandler
 
         throw new \UnexpectedValueException(sprintf(
             'The %s::onAuthenticationSuccess method must return null or a Response object. You returned %s.',
-            get_class($guardAuthenticator),
-            is_object($response) ? get_class($response) : gettype($response)
+            \get_class($guardAuthenticator),
+            \is_object($response) ? \get_class($response) : \gettype($response)
         ));
     }
 
@@ -115,8 +115,8 @@ class GuardAuthenticatorHandler
 
         throw new \UnexpectedValueException(sprintf(
             'The %s::onAuthenticationFailure method must return null or a Response object. You returned %s.',
-            get_class($guardAuthenticator),
-            is_object($response) ? get_class($response) : gettype($response)
+            \get_class($guardAuthenticator),
+            \is_object($response) ? \get_class($response) : \gettype($response)
         ));
     }
 
diff --git a/src/Symfony/Component/Security/Guard/Provider/GuardAuthenticationProvider.php b/src/Symfony/Component/Security/Guard/Provider/GuardAuthenticationProvider.php
index 62af83f23d..a2dfd2b860 100644
--- a/src/Symfony/Component/Security/Guard/Provider/GuardAuthenticationProvider.php
+++ b/src/Symfony/Component/Security/Guard/Provider/GuardAuthenticationProvider.php
@@ -102,23 +102,23 @@ class GuardAuthenticationProvider implements AuthenticationProviderInterface
         $user = $guardAuthenticator->getUser($token->getCredentials(), $this->userProvider);
 
         if (null === $user) {
-            throw new UsernameNotFoundException(sprintf('Null returned from %s::getUser()', get_class($guardAuthenticator)));
+            throw new UsernameNotFoundException(sprintf('Null returned from %s::getUser()', \get_class($guardAuthenticator)));
         }
 
         if (!$user instanceof UserInterface) {
-            throw new \UnexpectedValueException(sprintf('The %s::getUser() method must return a UserInterface. You returned %s.', get_class($guardAuthenticator), is_object($user) ? get_class($user) : gettype($user)));
+            throw new \UnexpectedValueException(sprintf('The %s::getUser() method must return a UserInterface. You returned %s.', \get_class($guardAuthenticator), \is_object($user) ? \get_class($user) : \gettype($user)));
         }
 
         $this->userChecker->checkPreAuth($user);
         if (true !== $guardAuthenticator->checkCredentials($token->getCredentials(), $user)) {
-            throw new BadCredentialsException(sprintf('Authentication failed because %s::checkCredentials() did not return true.', get_class($guardAuthenticator)));
+            throw new BadCredentialsException(sprintf('Authentication failed because %s::checkCredentials() did not return true.', \get_class($guardAuthenticator)));
         }
         $this->userChecker->checkPostAuth($user);
 
         // turn the UserInterface into a TokenInterface
         $authenticatedToken = $guardAuthenticator->createAuthenticatedToken($user, $this->providerKey);
         if (!$authenticatedToken instanceof TokenInterface) {
-            throw new \UnexpectedValueException(sprintf('The %s::createAuthenticatedToken() method must return a TokenInterface. You returned %s.', get_class($guardAuthenticator), is_object($authenticatedToken) ? get_class($authenticatedToken) : gettype($authenticatedToken)));
+            throw new \UnexpectedValueException(sprintf('The %s::createAuthenticatedToken() method must return a TokenInterface. You returned %s.', \get_class($guardAuthenticator), \is_object($authenticatedToken) ? \get_class($authenticatedToken) : \gettype($authenticatedToken)));
         }
 
         return $authenticatedToken;
diff --git a/src/Symfony/Component/Security/Http/Authentication/SimpleAuthenticationHandler.php b/src/Symfony/Component/Security/Http/Authentication/SimpleAuthenticationHandler.php
index 669dc13489..cca44c26f0 100644
--- a/src/Symfony/Component/Security/Http/Authentication/SimpleAuthenticationHandler.php
+++ b/src/Symfony/Component/Security/Http/Authentication/SimpleAuthenticationHandler.php
@@ -55,7 +55,7 @@ class SimpleAuthenticationHandler implements AuthenticationFailureHandlerInterfa
     {
         if ($this->simpleAuthenticator instanceof AuthenticationSuccessHandlerInterface) {
             if ($this->logger) {
-                $this->logger->debug('Selected an authentication success handler.', array('handler' => get_class($this->simpleAuthenticator)));
+                $this->logger->debug('Selected an authentication success handler.', array('handler' => \get_class($this->simpleAuthenticator)));
             }
 
             $response = $this->simpleAuthenticator->onAuthenticationSuccess($request, $token);
@@ -64,7 +64,7 @@ class SimpleAuthenticationHandler implements AuthenticationFailureHandlerInterfa
             }
 
             if (null !== $response) {
-                throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationSuccess method must return null to use the default success handler, or a Response object', get_class($this->simpleAuthenticator)));
+                throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationSuccess method must return null to use the default success handler, or a Response object', \get_class($this->simpleAuthenticator)));
             }
         }
 
@@ -82,7 +82,7 @@ class SimpleAuthenticationHandler implements AuthenticationFailureHandlerInterfa
     {
         if ($this->simpleAuthenticator instanceof AuthenticationFailureHandlerInterface) {
             if ($this->logger) {
-                $this->logger->debug('Selected an authentication failure handler.', array('handler' => get_class($this->simpleAuthenticator)));
+                $this->logger->debug('Selected an authentication failure handler.', array('handler' => \get_class($this->simpleAuthenticator)));
             }
 
             $response = $this->simpleAuthenticator->onAuthenticationFailure($request, $exception);
@@ -91,7 +91,7 @@ class SimpleAuthenticationHandler implements AuthenticationFailureHandlerInterfa
             }
 
             if (null !== $response) {
-                throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationFailure method must return null to use the default failure handler, or a Response object', get_class($this->simpleAuthenticator)));
+                throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationFailure method must return null to use the default failure handler, or a Response object', \get_class($this->simpleAuthenticator)));
             }
         }
 
diff --git a/src/Symfony/Component/Security/Http/Firewall/ContextListener.php b/src/Symfony/Component/Security/Http/Firewall/ContextListener.php
index a64261eedc..8f1e24f8b8 100644
--- a/src/Symfony/Component/Security/Http/Firewall/ContextListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/ContextListener.php
@@ -97,7 +97,7 @@ class ContextListener implements ListenerInterface
         if (null !== $this->logger) {
             $this->logger->debug('Read existing security token from the session.', array(
                 'key' => $this->sessionKey,
-                'token_class' => is_object($token) ? get_class($token) : null,
+                'token_class' => \is_object($token) ? \get_class($token) : null,
             ));
         }
 
@@ -164,7 +164,7 @@ class ContextListener implements ListenerInterface
 
         foreach ($this->userProviders as $provider) {
             if (!$provider instanceof UserProviderInterface) {
-                throw new \InvalidArgumentException(sprintf('User provider "%s" must implement "%s".', get_class($provider), UserProviderInterface::class));
+                throw new \InvalidArgumentException(sprintf('User provider "%s" must implement "%s".', \get_class($provider), UserProviderInterface::class));
             }
 
             try {
@@ -174,14 +174,14 @@ class ContextListener implements ListenerInterface
                 // tokens can be deauthenticated if the user has been changed.
                 if (!$token->isAuthenticated()) {
                     if (null !== $this->logger) {
-                        $this->logger->debug('Token was deauthenticated after trying to refresh it.', array('username' => $refreshedUser->getUsername(), 'provider' => get_class($provider)));
+                        $this->logger->debug('Token was deauthenticated after trying to refresh it.', array('username' => $refreshedUser->getUsername(), 'provider' => \get_class($provider)));
                     }
 
                     return null;
                 }
 
                 if (null !== $this->logger) {
-                    $context = array('provider' => get_class($provider), 'username' => $refreshedUser->getUsername());
+                    $context = array('provider' => \get_class($provider), 'username' => $refreshedUser->getUsername());
 
                     foreach ($token->getRoles() as $role) {
                         if ($role instanceof SwitchUserRole) {
@@ -198,7 +198,7 @@ class ContextListener implements ListenerInterface
                 // let's try the next user provider
             } catch (UsernameNotFoundException $e) {
                 if (null !== $this->logger) {
-                    $this->logger->warning('Username could not be found in the selected user provider.', array('username' => $e->getUsername(), 'provider' => get_class($provider)));
+                    $this->logger->warning('Username could not be found in the selected user provider.', array('username' => $e->getUsername(), 'provider' => \get_class($provider)));
                 }
 
                 $userNotFoundByProvider = true;
@@ -209,7 +209,7 @@ class ContextListener implements ListenerInterface
             return null;
         }
 
-        throw new \RuntimeException(sprintf('There is no user provider for user "%s".', get_class($user)));
+        throw new \RuntimeException(sprintf('There is no user provider for user "%s".', \get_class($user)));
     }
 
     private function safelyUnserialize($serializedToken)
diff --git a/src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php b/src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php
index 76ae56bd68..8e95ff3fdc 100644
--- a/src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/ExceptionListener.php
@@ -194,9 +194,9 @@ class ExceptionListener
         $response = $this->authenticationEntryPoint->start($request, $authException);
 
         if (!$response instanceof Response) {
-            $given = is_object($response) ? get_class($response) : gettype($response);
+            $given = \is_object($response) ? \get_class($response) : \gettype($response);
 
-            throw new \LogicException(sprintf('The %s::start() method must return a Response object (%s returned)', get_class($this->authenticationEntryPoint), $given));
+            throw new \LogicException(sprintf('The %s::start() method must return a Response object (%s returned)', \get_class($this->authenticationEntryPoint), $given));
         }
 
         return $response;
diff --git a/src/Symfony/Component/Security/Http/Firewall/SimplePreAuthenticationListener.php b/src/Symfony/Component/Security/Http/Firewall/SimplePreAuthenticationListener.php
index d3e2b0d1c2..911a4fd185 100644
--- a/src/Symfony/Component/Security/Http/Firewall/SimplePreAuthenticationListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/SimplePreAuthenticationListener.php
@@ -80,7 +80,7 @@ class SimplePreAuthenticationListener implements ListenerInterface
         $request = $event->getRequest();
 
         if (null !== $this->logger) {
-            $this->logger->info('Attempting SimplePreAuthentication.', array('key' => $this->providerKey, 'authenticator' => get_class($this->simpleAuthenticator)));
+            $this->logger->info('Attempting SimplePreAuthentication.', array('key' => $this->providerKey, 'authenticator' => \get_class($this->simpleAuthenticator)));
         }
 
         if ((null !== $token = $this->tokenStorage->getToken()) && !$this->trustResolver->isAnonymous($token)) {
@@ -109,7 +109,7 @@ class SimplePreAuthenticationListener implements ListenerInterface
             $this->tokenStorage->setToken(null);
 
             if (null !== $this->logger) {
-                $this->logger->info('SimplePreAuthentication request failed.', array('exception' => $e, 'authenticator' => get_class($this->simpleAuthenticator)));
+                $this->logger->info('SimplePreAuthentication request failed.', array('exception' => $e, 'authenticator' => \get_class($this->simpleAuthenticator)));
             }
 
             if ($this->simpleAuthenticator instanceof AuthenticationFailureHandlerInterface) {
@@ -117,7 +117,7 @@ class SimplePreAuthenticationListener implements ListenerInterface
                 if ($response instanceof Response) {
                     $event->setResponse($response);
                 } elseif (null !== $response) {
-                    throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationFailure method must return null or a Response object', get_class($this->simpleAuthenticator)));
+                    throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationFailure method must return null or a Response object', \get_class($this->simpleAuthenticator)));
                 }
             }
 
@@ -129,7 +129,7 @@ class SimplePreAuthenticationListener implements ListenerInterface
             if ($response instanceof Response) {
                 $event->setResponse($response);
             } elseif (null !== $response) {
-                throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationSuccess method must return null or a Response object', get_class($this->simpleAuthenticator)));
+                throw new \UnexpectedValueException(sprintf('The %s::onAuthenticationSuccess method must return null or a Response object', \get_class($this->simpleAuthenticator)));
             }
         }
     }
diff --git a/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordFormAuthenticationListener.php b/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordFormAuthenticationListener.php
index c4ee1bffaf..7c60633beb 100644
--- a/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordFormAuthenticationListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordFormAuthenticationListener.php
@@ -91,7 +91,7 @@ class UsernamePasswordFormAuthenticationListener extends AbstractAuthenticationL
 
         $username = trim($username);
 
-        if (strlen($username) > Security::MAX_USERNAME_LENGTH) {
+        if (\strlen($username) > Security::MAX_USERNAME_LENGTH) {
             throw new BadCredentialsException('Invalid username.');
         }
 
diff --git a/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordJsonAuthenticationListener.php b/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordJsonAuthenticationListener.php
index 2db39a4e9a..f0f1e42d7a 100644
--- a/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordJsonAuthenticationListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/UsernamePasswordJsonAuthenticationListener.php
@@ -104,15 +104,15 @@ class UsernamePasswordJsonAuthenticationListener implements ListenerInterface
                 throw new BadRequestHttpException(sprintf('The key "%s" must be provided.', $this->options['password_path']), $e);
             }
 
-            if (!is_string($username)) {
+            if (!\is_string($username)) {
                 throw new BadRequestHttpException(sprintf('The key "%s" must be a string.', $this->options['username_path']));
             }
 
-            if (strlen($username) > Security::MAX_USERNAME_LENGTH) {
+            if (\strlen($username) > Security::MAX_USERNAME_LENGTH) {
                 throw new BadCredentialsException('Invalid username.');
             }
 
-            if (!is_string($password)) {
+            if (!\is_string($password)) {
                 throw new BadRequestHttpException(sprintf('The key "%s" must be a string.', $this->options['password_path']));
             }
 
diff --git a/src/Symfony/Component/Security/Http/RememberMe/AbstractRememberMeServices.php b/src/Symfony/Component/Security/Http/RememberMe/AbstractRememberMeServices.php
index bc28709853..96c3e7dcfa 100644
--- a/src/Symfony/Component/Security/Http/RememberMe/AbstractRememberMeServices.php
+++ b/src/Symfony/Component/Security/Http/RememberMe/AbstractRememberMeServices.php
@@ -54,7 +54,7 @@ abstract class AbstractRememberMeServices implements RememberMeServicesInterface
         if (empty($providerKey)) {
             throw new \InvalidArgumentException('$providerKey must not be empty.');
         }
-        if (0 === count($userProviders)) {
+        if (0 === \count($userProviders)) {
             throw new \InvalidArgumentException('You must provide at least one user provider.');
         }
 
diff --git a/src/Symfony/Component/Security/Http/RememberMe/PersistentTokenBasedRememberMeServices.php b/src/Symfony/Component/Security/Http/RememberMe/PersistentTokenBasedRememberMeServices.php
index ff6305f454..518e13263d 100644
--- a/src/Symfony/Component/Security/Http/RememberMe/PersistentTokenBasedRememberMeServices.php
+++ b/src/Symfony/Component/Security/Http/RememberMe/PersistentTokenBasedRememberMeServices.php
@@ -47,7 +47,7 @@ class PersistentTokenBasedRememberMeServices extends AbstractRememberMeServices
 
         // Delete cookie from the tokenProvider
         if (null !== ($cookie = $request->cookies->get($this->options['name']))
-            && 2 === count($parts = $this->decodeCookie($cookie))
+            && 2 === \count($parts = $this->decodeCookie($cookie))
         ) {
             list($series) = $parts;
             $this->tokenProvider->deleteTokenBySeries($series);
@@ -59,7 +59,7 @@ class PersistentTokenBasedRememberMeServices extends AbstractRememberMeServices
      */
     protected function processAutoLoginCookie(array $cookieParts, Request $request)
     {
-        if (2 !== count($cookieParts)) {
+        if (2 !== \count($cookieParts)) {
             throw new AuthenticationException('The cookie is invalid.');
         }
 
@@ -103,7 +103,7 @@ class PersistentTokenBasedRememberMeServices extends AbstractRememberMeServices
 
         $this->tokenProvider->createNewToken(
             new PersistentToken(
-                get_class($user = $token->getUser()),
+                \get_class($user = $token->getUser()),
                 $user->getUsername(),
                 $series,
                 $tokenValue,
diff --git a/src/Symfony/Component/Security/Http/RememberMe/TokenBasedRememberMeServices.php b/src/Symfony/Component/Security/Http/RememberMe/TokenBasedRememberMeServices.php
index ab5aba9444..55eee415a4 100644
--- a/src/Symfony/Component/Security/Http/RememberMe/TokenBasedRememberMeServices.php
+++ b/src/Symfony/Component/Security/Http/RememberMe/TokenBasedRememberMeServices.php
@@ -31,7 +31,7 @@ class TokenBasedRememberMeServices extends AbstractRememberMeServices
      */
     protected function processAutoLoginCookie(array $cookieParts, Request $request)
     {
-        if (4 !== count($cookieParts)) {
+        if (4 !== \count($cookieParts)) {
             throw new AuthenticationException('The cookie is invalid.');
         }
 
@@ -50,7 +50,7 @@ class TokenBasedRememberMeServices extends AbstractRememberMeServices
         }
 
         if (!$user instanceof UserInterface) {
-            throw new \RuntimeException(sprintf('The UserProviderInterface implementation must return an instance of UserInterface, but returned "%s".', get_class($user)));
+            throw new \RuntimeException(sprintf('The UserProviderInterface implementation must return an instance of UserInterface, but returned "%s".', \get_class($user)));
         }
 
         if (true !== hash_equals($this->generateCookieHash($class, $username, $expires, $user->getPassword()), $hash)) {
@@ -71,7 +71,7 @@ class TokenBasedRememberMeServices extends AbstractRememberMeServices
     {
         $user = $token->getUser();
         $expires = time() + $this->options['lifetime'];
-        $value = $this->generateCookieValue(get_class($user), $user->getUsername(), $expires, $user->getPassword());
+        $value = $this->generateCookieValue(\get_class($user), $user->getUsername(), $expires, $user->getPassword());
 
         $response->headers->setCookie(
             new Cookie(
diff --git a/src/Symfony/Component/Security/Http/Tests/Controller/UserValueResolverTest.php b/src/Symfony/Component/Security/Http/Tests/Controller/UserValueResolverTest.php
index 62f4c12621..264272b125 100644
--- a/src/Symfony/Component/Security/Http/Tests/Controller/UserValueResolverTest.php
+++ b/src/Symfony/Component/Security/Http/Tests/Controller/UserValueResolverTest.php
@@ -40,7 +40,7 @@ class UserValueResolverTest extends TestCase
         $tokenStorage->setToken($token);
 
         $resolver = new UserValueResolver($tokenStorage);
-        $metadata = new ArgumentMetadata('foo', get_class($mock), false, false, null);
+        $metadata = new ArgumentMetadata('foo', \get_class($mock), false, false, null);
 
         $this->assertFalse($resolver->supports(Request::create('/'), $metadata));
     }
diff --git a/src/Symfony/Component/Security/Http/Tests/RememberMe/AbstractRememberMeServicesTest.php b/src/Symfony/Component/Security/Http/Tests/RememberMe/AbstractRememberMeServicesTest.php
index 886743c1d3..a60fda707d 100644
--- a/src/Symfony/Component/Security/Http/Tests/RememberMe/AbstractRememberMeServicesTest.php
+++ b/src/Symfony/Component/Security/Http/Tests/RememberMe/AbstractRememberMeServicesTest.php
@@ -304,7 +304,7 @@ class AbstractRememberMeServicesTest extends TestCase
 
     private function callProtected($object, $method, array $args)
     {
-        $reflection = new \ReflectionClass(get_class($object));
+        $reflection = new \ReflectionClass(\get_class($object));
         $reflectionMethod = $reflection->getMethod($method);
         $reflectionMethod->setAccessible(true);
 
diff --git a/src/Symfony/Component/Serializer/Annotation/DiscriminatorMap.php b/src/Symfony/Component/Serializer/Annotation/DiscriminatorMap.php
index 61b952610c..847ec7c74a 100644
--- a/src/Symfony/Component/Serializer/Annotation/DiscriminatorMap.php
+++ b/src/Symfony/Component/Serializer/Annotation/DiscriminatorMap.php
@@ -41,11 +41,11 @@ class DiscriminatorMap
     public function __construct(array $data)
     {
         if (empty($data['typeProperty'])) {
-            throw new InvalidArgumentException(sprintf('Parameter "typeProperty" of annotation "%s" cannot be empty.', get_class($this)));
+            throw new InvalidArgumentException(sprintf('Parameter "typeProperty" of annotation "%s" cannot be empty.', \get_class($this)));
         }
 
         if (empty($data['mapping'])) {
-            throw new InvalidArgumentException(sprintf('Parameter "mapping" of annotation "%s" cannot be empty.', get_class($this)));
+            throw new InvalidArgumentException(sprintf('Parameter "mapping" of annotation "%s" cannot be empty.', \get_class($this)));
         }
 
         $this->typeProperty = $data['typeProperty'];
diff --git a/src/Symfony/Component/Serializer/Annotation/MaxDepth.php b/src/Symfony/Component/Serializer/Annotation/MaxDepth.php
index 1f41948d6d..a274c20d85 100644
--- a/src/Symfony/Component/Serializer/Annotation/MaxDepth.php
+++ b/src/Symfony/Component/Serializer/Annotation/MaxDepth.php
@@ -31,11 +31,11 @@ class MaxDepth
     public function __construct(array $data)
     {
         if (!isset($data['value'])) {
-            throw new InvalidArgumentException(sprintf('Parameter of annotation "%s" should be set.', get_class($this)));
+            throw new InvalidArgumentException(sprintf('Parameter of annotation "%s" should be set.', \get_class($this)));
         }
 
-        if (!is_int($data['value']) || $data['value'] <= 0) {
-            throw new InvalidArgumentException(sprintf('Parameter of annotation "%s" must be a positive integer.', get_class($this)));
+        if (!\is_int($data['value']) || $data['value'] <= 0) {
+            throw new InvalidArgumentException(sprintf('Parameter of annotation "%s" must be a positive integer.', \get_class($this)));
         }
 
         $this->maxDepth = $data['value'];
diff --git a/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php b/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php
index b73b55cc10..ba1a62526c 100644
--- a/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php
+++ b/src/Symfony/Component/Serializer/Encoder/CsvEncoder.php
@@ -53,7 +53,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
     {
         $handle = fopen('php://temp,', 'w+');
 
-        if (!is_array($data)) {
+        if (!\is_array($data)) {
             $data = array(array($data));
         } elseif (empty($data)) {
             $data = array(array());
@@ -61,7 +61,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
             // Sequential arrays of arrays are considered as collections
             $i = 0;
             foreach ($data as $key => $value) {
-                if ($i !== $key || !is_array($value)) {
+                if ($i !== $key || !\is_array($value)) {
                     $data = array($data);
                     break;
                 }
@@ -120,7 +120,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
         list($delimiter, $enclosure, $escapeChar, $keySeparator) = $this->getCsvOptions($context);
 
         while (false !== ($cols = fgetcsv($handle, 0, $delimiter, $enclosure, $escapeChar))) {
-            $nbCols = count($cols);
+            $nbCols = \count($cols);
 
             if (null === $headers) {
                 $nbHeaders = $nbCols;
@@ -128,7 +128,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
                 foreach ($cols as $col) {
                     $header = explode($keySeparator, $col);
                     $headers[] = $header;
-                    $headerCount[] = count($header);
+                    $headerCount[] = \count($header);
                 }
 
                 continue;
@@ -188,7 +188,7 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
     private function flatten(array $array, array &$result, string $keySeparator, string $parentKey = '', bool $escapeFormulas = false)
     {
         foreach ($array as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $this->flatten($value, $result, $keySeparator, $parentKey.$key.$keySeparator, $escapeFormulas);
             } else {
                 if ($escapeFormulas && \in_array(substr($value, 0, 1), $this->formulasStartCharacters, true)) {
@@ -209,8 +209,8 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
         $headers = isset($context[self::HEADERS_KEY]) ? $context[self::HEADERS_KEY] : array();
         $escapeFormulas = isset($context[self::ESCAPE_FORMULAS_KEY]) ? $context[self::ESCAPE_FORMULAS_KEY] : $this->escapeFormulas;
 
-        if (!is_array($headers)) {
-            throw new InvalidArgumentException(sprintf('The "%s" context variable must be an array or null, given "%s".', self::HEADERS_KEY, gettype($headers)));
+        if (!\is_array($headers)) {
+            throw new InvalidArgumentException(sprintf('The "%s" context variable must be an array or null, given "%s".', self::HEADERS_KEY, \gettype($headers)));
         }
 
         return array($delimiter, $enclosure, $escapeChar, $keySeparator, $headers, $escapeFormulas);
@@ -234,11 +234,11 @@ class CsvEncoder implements EncoderInterface, DecoderInterface
                 }
 
                 if (null === $previousHeader) {
-                    $n = count($headers);
+                    $n = \count($headers);
                 } else {
                     $n = $flippedHeaders[$previousHeader] + 1;
 
-                    for ($j = count($headers); $j > $n; --$j) {
+                    for ($j = \count($headers); $j > $n; --$j) {
                         ++$flippedHeaders[$headers[$j] = $headers[$j - 1]];
                     }
                 }
diff --git a/src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorFromClassMetadata.php b/src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorFromClassMetadata.php
index 7196651624..6ed1bb8ebe 100644
--- a/src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorFromClassMetadata.php
+++ b/src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorFromClassMetadata.php
@@ -54,7 +54,7 @@ class ClassDiscriminatorFromClassMetadata implements ClassDiscriminatorResolverI
             }
         }
 
-        $cacheKey = is_object($object) ? get_class($object) : $object;
+        $cacheKey = \is_object($object) ? \get_class($object) : $object;
         if (!array_key_exists($cacheKey, $this->mappingForMappedObjectCache)) {
             $this->mappingForMappedObjectCache[$cacheKey] = $this->resolveMappingForMappedObject($object);
         }
diff --git a/src/Symfony/Component/Serializer/Mapping/Factory/ClassResolverTrait.php b/src/Symfony/Component/Serializer/Mapping/Factory/ClassResolverTrait.php
index e93277a6be..6bb647ebee 100644
--- a/src/Symfony/Component/Serializer/Mapping/Factory/ClassResolverTrait.php
+++ b/src/Symfony/Component/Serializer/Mapping/Factory/ClassResolverTrait.php
@@ -33,7 +33,7 @@ trait ClassResolverTrait
      */
     private function getClass($value)
     {
-        if (is_string($value)) {
+        if (\is_string($value)) {
             if (!class_exists($value) && !interface_exists($value)) {
                 throw new InvalidArgumentException(sprintf('The class or interface "%s" does not exist.', $value));
             }
@@ -41,10 +41,10 @@ trait ClassResolverTrait
             return ltrim($value, '\\');
         }
 
-        if (!is_object($value)) {
-            throw new InvalidArgumentException(sprintf('Cannot create metadata for non-objects. Got: "%s"', gettype($value)));
+        if (!\is_object($value)) {
+            throw new InvalidArgumentException(sprintf('Cannot create metadata for non-objects. Got: "%s"', \gettype($value)));
         }
 
-        return get_class($value);
+        return \get_class($value);
     }
 }
diff --git a/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php b/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php
index a1639b5209..10345afc05 100644
--- a/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/Serializer/Mapping/Loader/YamlFileLoader.php
@@ -79,7 +79,7 @@ class YamlFileLoader extends FileLoader
                 }
 
                 if (isset($data['max_depth'])) {
-                    if (!is_int($data['max_depth'])) {
+                    if (!\is_int($data['max_depth'])) {
                         throw new MappingException(sprintf('The "max_depth" value must be an integer in "%s" for the attribute "%s" of the class "%s".', $this->file, $attribute, $classMetadata->getName()));
                     }
 
diff --git a/src/Symfony/Component/Serializer/Normalizer/AbstractNormalizer.php b/src/Symfony/Component/Serializer/Normalizer/AbstractNormalizer.php
index f8344cca52..57a63d25d9 100644
--- a/src/Symfony/Component/Serializer/Normalizer/AbstractNormalizer.php
+++ b/src/Symfony/Component/Serializer/Normalizer/AbstractNormalizer.php
@@ -267,7 +267,7 @@ abstract class AbstractNormalizer implements NormalizerInterface, DenormalizerIn
      */
     protected function isAllowedAttribute($classOrObject, $attribute, $format = null, array $context = array())
     {
-        if (in_array($attribute, $this->ignoredAttributes)) {
+        if (\in_array($attribute, $this->ignoredAttributes)) {
             return false;
         }
 
@@ -276,8 +276,8 @@ abstract class AbstractNormalizer implements NormalizerInterface, DenormalizerIn
             return true;
         }
 
-        if (isset($context[self::ATTRIBUTES]) && is_array($context[self::ATTRIBUTES])) {
-            return in_array($attribute, $context[self::ATTRIBUTES], true);
+        if (isset($context[self::ATTRIBUTES]) && \is_array($context[self::ATTRIBUTES])) {
+            return \in_array($attribute, $context[self::ATTRIBUTES], true);
         }
 
         return true;
diff --git a/src/Symfony/Component/Serializer/Normalizer/AbstractObjectNormalizer.php b/src/Symfony/Component/Serializer/Normalizer/AbstractObjectNormalizer.php
index af0c45609c..c88f061003 100644
--- a/src/Symfony/Component/Serializer/Normalizer/AbstractObjectNormalizer.php
+++ b/src/Symfony/Component/Serializer/Normalizer/AbstractObjectNormalizer.php
@@ -310,7 +310,7 @@ abstract class AbstractObjectNormalizer extends AbstractNormalizer
 
                 // Fix a collection that contains the only one element
                 // This is special to xml format only
-                if ('xml' === $format && !is_int(key($data))) {
+                if ('xml' === $format && !\is_int(key($data))) {
                     $data = array($data);
                 }
 
@@ -341,7 +341,7 @@ abstract class AbstractObjectNormalizer extends AbstractNormalizer
             // PHP's json_decode automatically converts Numbers without a decimal part to integers.
             // To circumvent this behavior, integers are converted to floats when denormalizing JSON based formats and when
             // a float is expected.
-            if (Type::BUILTIN_TYPE_FLOAT === $builtinType && is_int($data) && false !== strpos($format, JsonEncoder::FORMAT)) {
+            if (Type::BUILTIN_TYPE_FLOAT === $builtinType && \is_int($data) && false !== strpos($format, JsonEncoder::FORMAT)) {
                 return (float) $data;
             }
 
@@ -354,7 +354,7 @@ abstract class AbstractObjectNormalizer extends AbstractNormalizer
             return $data;
         }
 
-        throw new NotNormalizableValueException(sprintf('The type of the "%s" attribute for class "%s" must be one of "%s" ("%s" given).', $attribute, $currentClass, implode('", "', array_keys($expectedTypes)), gettype($data)));
+        throw new NotNormalizableValueException(sprintf('The type of the "%s" attribute for class "%s" must be one of "%s" ("%s" given).', $attribute, $currentClass, implode('", "', array_keys($expectedTypes)), \gettype($data)));
     }
 
     /**
diff --git a/src/Symfony/Component/Serializer/Normalizer/ArrayDenormalizer.php b/src/Symfony/Component/Serializer/Normalizer/ArrayDenormalizer.php
index a52b24c31e..81e11dcd25 100644
--- a/src/Symfony/Component/Serializer/Normalizer/ArrayDenormalizer.php
+++ b/src/Symfony/Component/Serializer/Normalizer/ArrayDenormalizer.php
@@ -41,8 +41,8 @@ class ArrayDenormalizer implements ContextAwareDenormalizerInterface, Serializer
         if (null === $this->serializer) {
             throw new BadMethodCallException('Please set a serializer before calling denormalize()!');
         }
-        if (!is_array($data)) {
-            throw new InvalidArgumentException('Data expected to be an array, '.gettype($data).' given.');
+        if (!\is_array($data)) {
+            throw new InvalidArgumentException('Data expected to be an array, '.\gettype($data).' given.');
         }
         if ('[]' !== substr($class, -2)) {
             throw new InvalidArgumentException('Unsupported class: '.$class);
@@ -53,8 +53,8 @@ class ArrayDenormalizer implements ContextAwareDenormalizerInterface, Serializer
 
         $builtinType = isset($context['key_type']) ? $context['key_type']->getBuiltinType() : null;
         foreach ($data as $key => $value) {
-            if (null !== $builtinType && !call_user_func('is_'.$builtinType, $key)) {
-                throw new NotNormalizableValueException(sprintf('The type of the key "%s" must be "%s" ("%s" given).', $key, $builtinType, gettype($key)));
+            if (null !== $builtinType && !\call_user_func('is_'.$builtinType, $key)) {
+                throw new NotNormalizableValueException(sprintf('The type of the key "%s" must be "%s" ("%s" given).', $key, $builtinType, \gettype($key)));
             }
 
             $data[$key] = $serializer->denormalize($value, $class, $format, $context);
diff --git a/src/Symfony/Component/Serializer/Normalizer/DateIntervalNormalizer.php b/src/Symfony/Component/Serializer/Normalizer/DateIntervalNormalizer.php
index 6fdf8b4a8a..2dce4d5b54 100644
--- a/src/Symfony/Component/Serializer/Normalizer/DateIntervalNormalizer.php
+++ b/src/Symfony/Component/Serializer/Normalizer/DateIntervalNormalizer.php
@@ -71,8 +71,8 @@ class DateIntervalNormalizer implements NormalizerInterface, DenormalizerInterfa
      */
     public function denormalize($data, $class, $format = null, array $context = array())
     {
-        if (!is_string($data)) {
-            throw new InvalidArgumentException(sprintf('Data expected to be a string, %s given.', gettype($data)));
+        if (!\is_string($data)) {
+            throw new InvalidArgumentException(sprintf('Data expected to be a string, %s given.', \gettype($data)));
         }
 
         if (!$this->isISO8601($data)) {
diff --git a/src/Symfony/Component/Serializer/Normalizer/ObjectToPopulateTrait.php b/src/Symfony/Component/Serializer/Normalizer/ObjectToPopulateTrait.php
index ac64788916..7150a6e6ee 100644
--- a/src/Symfony/Component/Serializer/Normalizer/ObjectToPopulateTrait.php
+++ b/src/Symfony/Component/Serializer/Normalizer/ObjectToPopulateTrait.php
@@ -28,7 +28,7 @@ trait ObjectToPopulateTrait
     {
         $key = $key ?: 'object_to_populate';
 
-        if (isset($context[$key]) && is_object($context[$key]) && $context[$key] instanceof $class) {
+        if (isset($context[$key]) && \is_object($context[$key]) && $context[$key] instanceof $class) {
             return $context[$key];
         }
 
diff --git a/src/Symfony/Component/Serializer/Tests/Normalizer/AbstractObjectNormalizerTest.php b/src/Symfony/Component/Serializer/Tests/Normalizer/AbstractObjectNormalizerTest.php
index 7aa6a76a7d..a7f8dd8af9 100644
--- a/src/Symfony/Component/Serializer/Tests/Normalizer/AbstractObjectNormalizerTest.php
+++ b/src/Symfony/Component/Serializer/Tests/Normalizer/AbstractObjectNormalizerTest.php
@@ -180,7 +180,7 @@ class AbstractObjectNormalizerDummy extends AbstractObjectNormalizer
 
     protected function isAllowedAttribute($classOrObject, $attribute, $format = null, array $context = array())
     {
-        return in_array($attribute, array('foo', 'baz'));
+        return \in_array($attribute, array('foo', 'baz'));
     }
 
     public function instantiateObject(array &$data, $class, array &$context, \ReflectionClass $reflectionClass, $allowedAttributes, string $format = null)
diff --git a/src/Symfony/Component/Serializer/Tests/Normalizer/CustomNormalizerTest.php b/src/Symfony/Component/Serializer/Tests/Normalizer/CustomNormalizerTest.php
index e5d0d44570..fe2c302ebe 100644
--- a/src/Symfony/Component/Serializer/Tests/Normalizer/CustomNormalizerTest.php
+++ b/src/Symfony/Component/Serializer/Tests/Normalizer/CustomNormalizerTest.php
@@ -47,11 +47,11 @@ class CustomNormalizerTest extends TestCase
 
     public function testDeserialize()
     {
-        $obj = $this->normalizer->denormalize('foo', get_class(new ScalarDummy()), 'xml');
+        $obj = $this->normalizer->denormalize('foo', \get_class(new ScalarDummy()), 'xml');
         $this->assertEquals('foo', $obj->xmlFoo);
         $this->assertNull($obj->foo);
 
-        $obj = $this->normalizer->denormalize('foo', get_class(new ScalarDummy()), 'json');
+        $obj = $this->normalizer->denormalize('foo', \get_class(new ScalarDummy()), 'json');
         $this->assertEquals('foo', $obj->foo);
         $this->assertNull($obj->xmlFoo);
     }
diff --git a/src/Symfony/Component/Serializer/Tests/Normalizer/GetSetMethodNormalizerTest.php b/src/Symfony/Component/Serializer/Tests/Normalizer/GetSetMethodNormalizerTest.php
index 16b04fb5d6..ca76cd1009 100644
--- a/src/Symfony/Component/Serializer/Tests/Normalizer/GetSetMethodNormalizerTest.php
+++ b/src/Symfony/Component/Serializer/Tests/Normalizer/GetSetMethodNormalizerTest.php
@@ -373,7 +373,7 @@ class GetSetMethodNormalizerTest extends TestCase
             array(
                 array(
                     'bar' => function ($bars) {
-                        return count($bars);
+                        return \count($bars);
                     },
                 ),
                 array(new GetConstructorDummy('baz', '', false), new GetConstructorDummy('quux', '', false)),
@@ -433,7 +433,7 @@ class GetSetMethodNormalizerTest extends TestCase
         $serializer = new Serializer(array($this->normalizer));
         $this->normalizer->setSerializer($serializer);
         $this->normalizer->setCircularReferenceHandler(function ($obj) {
-            return get_class($obj);
+            return \get_class($obj);
         });
 
         $obj = new CircularReferenceDummy();
diff --git a/src/Symfony/Component/Serializer/Tests/Normalizer/ObjectNormalizerTest.php b/src/Symfony/Component/Serializer/Tests/Normalizer/ObjectNormalizerTest.php
index 7619392543..8a0b69c5e9 100644
--- a/src/Symfony/Component/Serializer/Tests/Normalizer/ObjectNormalizerTest.php
+++ b/src/Symfony/Component/Serializer/Tests/Normalizer/ObjectNormalizerTest.php
@@ -477,7 +477,7 @@ class ObjectNormalizerTest extends TestCase
             array(
                 array(
                     'bar' => function ($bars) {
-                        return count($bars);
+                        return \count($bars);
                     },
                 ),
                 array(new ObjectConstructorDummy('baz', '', false), new ObjectConstructorDummy('quux', '', false)),
@@ -537,7 +537,7 @@ class ObjectNormalizerTest extends TestCase
         $serializer = new Serializer(array($this->normalizer));
         $this->normalizer->setSerializer($serializer);
         $this->normalizer->setCircularReferenceHandler(function ($obj) {
-            return get_class($obj);
+            return \get_class($obj);
         });
 
         $obj = new CircularReferenceDummy();
@@ -1082,11 +1082,11 @@ class FormatAndContextAwareNormalizer extends ObjectNormalizer
 {
     protected function isAllowedAttribute($classOrObject, $attribute, $format = null, array $context = array())
     {
-        if (in_array($attribute, array('foo', 'bar')) && 'foo_and_bar_included' === $format) {
+        if (\in_array($attribute, array('foo', 'bar')) && 'foo_and_bar_included' === $format) {
             return true;
         }
 
-        if (in_array($attribute, array('foo', 'bar')) && isset($context['include_foo_and_bar']) && true === $context['include_foo_and_bar']) {
+        if (\in_array($attribute, array('foo', 'bar')) && isset($context['include_foo_and_bar']) && true === $context['include_foo_and_bar']) {
             return true;
         }
 
diff --git a/src/Symfony/Component/Serializer/Tests/Normalizer/PropertyNormalizerTest.php b/src/Symfony/Component/Serializer/Tests/Normalizer/PropertyNormalizerTest.php
index ffcbacd063..f5b0e6a53b 100644
--- a/src/Symfony/Component/Serializer/Tests/Normalizer/PropertyNormalizerTest.php
+++ b/src/Symfony/Component/Serializer/Tests/Normalizer/PropertyNormalizerTest.php
@@ -310,7 +310,7 @@ class PropertyNormalizerTest extends TestCase
             array(
                 array(
                     'bar' => function ($bars) {
-                        return count($bars);
+                        return \count($bars);
                     },
                 ),
                 array(new PropertyConstructorDummy('baz', ''), new PropertyConstructorDummy('quux', '')),
@@ -354,7 +354,7 @@ class PropertyNormalizerTest extends TestCase
         $serializer = new Serializer(array($this->normalizer));
         $this->normalizer->setSerializer($serializer);
         $this->normalizer->setCircularReferenceHandler(function ($obj) {
-            return get_class($obj);
+            return \get_class($obj);
         });
 
         $obj = new PropertyCircularReferenceDummy();
diff --git a/src/Symfony/Component/Stopwatch/Stopwatch.php b/src/Symfony/Component/Stopwatch/Stopwatch.php
index c203258e01..4c871969ad 100644
--- a/src/Symfony/Component/Stopwatch/Stopwatch.php
+++ b/src/Symfony/Component/Stopwatch/Stopwatch.php
@@ -87,7 +87,7 @@ class Stopwatch implements ResetInterface
     {
         $this->stop('__section__');
 
-        if (1 == count($this->activeSections)) {
+        if (1 == \count($this->activeSections)) {
             throw new \LogicException('There is no started section to stop.');
         }
 
diff --git a/src/Symfony/Component/Stopwatch/StopwatchEvent.php b/src/Symfony/Component/Stopwatch/StopwatchEvent.php
index de1259a9f1..99ed6de282 100644
--- a/src/Symfony/Component/Stopwatch/StopwatchEvent.php
+++ b/src/Symfony/Component/Stopwatch/StopwatchEvent.php
@@ -53,7 +53,7 @@ class StopwatchEvent
     public function __construct(float $origin, string $category = null, bool $morePrecision = false)
     {
         $this->origin = $this->formatTime($origin);
-        $this->category = is_string($category) ? $category : 'default';
+        $this->category = \is_string($category) ? $category : 'default';
         $this->morePrecision = $morePrecision;
     }
 
@@ -98,7 +98,7 @@ class StopwatchEvent
      */
     public function stop()
     {
-        if (!count($this->started)) {
+        if (!\count($this->started)) {
             throw new \LogicException('stop() called but start() has not been called before.');
         }
 
@@ -132,7 +132,7 @@ class StopwatchEvent
      */
     public function ensureStopped()
     {
-        while (count($this->started)) {
+        while (\count($this->started)) {
             $this->stop();
         }
     }
@@ -164,7 +164,7 @@ class StopwatchEvent
      */
     public function getEndTime()
     {
-        $count = count($this->periods);
+        $count = \count($this->periods);
 
         return $count ? $this->periods[$count - 1]->getEndTime() : 0;
     }
@@ -177,8 +177,8 @@ class StopwatchEvent
     public function getDuration()
     {
         $periods = $this->periods;
-        $stopped = count($periods);
-        $left = count($this->started) - $stopped;
+        $stopped = \count($periods);
+        $left = \count($this->started) - $stopped;
 
         for ($i = 0; $i < $left; ++$i) {
             $index = $stopped + $i;
diff --git a/src/Symfony/Component/Templating/Helper/SlotsHelper.php b/src/Symfony/Component/Templating/Helper/SlotsHelper.php
index 8fa5ff5ff2..e5faf7fe88 100644
--- a/src/Symfony/Component/Templating/Helper/SlotsHelper.php
+++ b/src/Symfony/Component/Templating/Helper/SlotsHelper.php
@@ -33,7 +33,7 @@ class SlotsHelper extends Helper
      */
     public function start($name)
     {
-        if (in_array($name, $this->openSlots)) {
+        if (\in_array($name, $this->openSlots)) {
             throw new \InvalidArgumentException(sprintf('A slot named "%s" is already started.', $name));
         }
 
diff --git a/src/Symfony/Component/Templating/Loader/FilesystemLoader.php b/src/Symfony/Component/Templating/Loader/FilesystemLoader.php
index 7bb483ad6b..e3de9d5628 100644
--- a/src/Symfony/Component/Templating/Loader/FilesystemLoader.php
+++ b/src/Symfony/Component/Templating/Loader/FilesystemLoader.php
@@ -102,7 +102,7 @@ class FilesystemLoader extends Loader
     protected static function isAbsolutePath($file)
     {
         if ('/' == $file[0] || '\\' == $file[0]
-            || (strlen($file) > 3 && ctype_alpha($file[0])
+            || (\strlen($file) > 3 && ctype_alpha($file[0])
                 && ':' == $file[1]
                 && ('\\' == $file[2] || '/' == $file[2])
             )
diff --git a/src/Symfony/Component/Templating/PhpEngine.php b/src/Symfony/Component/Templating/PhpEngine.php
index ff1897ba38..f328ee535a 100644
--- a/src/Symfony/Component/Templating/PhpEngine.php
+++ b/src/Symfony/Component/Templating/PhpEngine.php
@@ -224,7 +224,7 @@ class PhpEngine implements EngineInterface, \ArrayAccess
     public function addHelpers(array $helpers)
     {
         foreach ($helpers as $alias => $helper) {
-            $this->set($helper, is_int($alias) ? null : $alias);
+            $this->set($helper, \is_int($alias) ? null : $alias);
         }
     }
 
@@ -313,13 +313,13 @@ class PhpEngine implements EngineInterface, \ArrayAccess
         // the performance when the same value is escaped multiple times (e.g. loops)
         if (is_scalar($value)) {
             if (!isset(self::$escaperCache[$context][$value])) {
-                self::$escaperCache[$context][$value] = call_user_func($this->getEscaper($context), $value);
+                self::$escaperCache[$context][$value] = \call_user_func($this->getEscaper($context), $value);
             }
 
             return self::$escaperCache[$context][$value];
         }
 
-        return call_user_func($this->getEscaper($context), $value);
+        return \call_user_func($this->getEscaper($context), $value);
     }
 
     /**
@@ -431,7 +431,7 @@ class PhpEngine implements EngineInterface, \ArrayAccess
                 function ($value) use ($flags) {
                     // Numbers and Boolean values get turned into strings which can cause problems
                     // with type comparisons (e.g. === or is_int() etc).
-                    return is_string($value) ? htmlspecialchars($value, $flags, $this->getCharset(), false) : $value;
+                    return \is_string($value) ? htmlspecialchars($value, $flags, $this->getCharset(), false) : $value;
                 },
 
             'js' =>
diff --git a/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php b/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php
index 022bad48f8..b6be9d69b8 100644
--- a/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php
+++ b/src/Symfony/Component/Translation/Catalogue/AbstractOperation.php
@@ -91,7 +91,7 @@ abstract class AbstractOperation implements OperationInterface
      */
     public function getMessages($domain)
     {
-        if (!in_array($domain, $this->getDomains())) {
+        if (!\in_array($domain, $this->getDomains())) {
             throw new InvalidArgumentException(sprintf('Invalid domain: %s.', $domain));
         }
 
@@ -107,7 +107,7 @@ abstract class AbstractOperation implements OperationInterface
      */
     public function getNewMessages($domain)
     {
-        if (!in_array($domain, $this->getDomains())) {
+        if (!\in_array($domain, $this->getDomains())) {
             throw new InvalidArgumentException(sprintf('Invalid domain: %s.', $domain));
         }
 
@@ -123,7 +123,7 @@ abstract class AbstractOperation implements OperationInterface
      */
     public function getObsoleteMessages($domain)
     {
-        if (!in_array($domain, $this->getDomains())) {
+        if (!\in_array($domain, $this->getDomains())) {
             throw new InvalidArgumentException(sprintf('Invalid domain: %s.', $domain));
         }
 
diff --git a/src/Symfony/Component/Translation/Command/XliffLintCommand.php b/src/Symfony/Component/Translation/Command/XliffLintCommand.php
index 325ca327aa..bf48e775d3 100644
--- a/src/Symfony/Component/Translation/Command/XliffLintCommand.php
+++ b/src/Symfony/Component/Translation/Command/XliffLintCommand.php
@@ -140,7 +140,7 @@ EOF
                 );
         }
 
-        return array('file' => $file, 'valid' => 0 === count($errors), 'messages' => $errors);
+        return array('file' => $file, 'valid' => 0 === \count($errors), 'messages' => $errors);
     }
 
     private function display(SymfonyStyle $io, array $files)
@@ -157,7 +157,7 @@ EOF
 
     private function displayTxt(SymfonyStyle $io, array $filesInfo)
     {
-        $countFiles = count($filesInfo);
+        $countFiles = \count($filesInfo);
         $erroredFiles = 0;
 
         foreach ($filesInfo as $info) {
@@ -207,7 +207,7 @@ EOF
         }
 
         foreach ($this->getDirectoryIterator($fileOrDirectory) as $file) {
-            if (!in_array($file->getExtension(), array('xlf', 'xliff'))) {
+            if (!\in_array($file->getExtension(), array('xlf', 'xliff'))) {
                 continue;
             }
 
@@ -239,7 +239,7 @@ EOF
         };
 
         if (null !== $this->directoryIteratorProvider) {
-            return call_user_func($this->directoryIteratorProvider, $directory, $default);
+            return \call_user_func($this->directoryIteratorProvider, $directory, $default);
         }
 
         return $default($directory);
@@ -252,7 +252,7 @@ EOF
         };
 
         if (null !== $this->isReadableProvider) {
-            return call_user_func($this->isReadableProvider, $fileOrDirectory, $default);
+            return \call_user_func($this->isReadableProvider, $fileOrDirectory, $default);
         }
 
         return $default($fileOrDirectory);
diff --git a/src/Symfony/Component/Translation/DataCollector/TranslationDataCollector.php b/src/Symfony/Component/Translation/DataCollector/TranslationDataCollector.php
index 5d97a67006..edd712dd14 100644
--- a/src/Symfony/Component/Translation/DataCollector/TranslationDataCollector.php
+++ b/src/Symfony/Component/Translation/DataCollector/TranslationDataCollector.php
@@ -99,7 +99,7 @@ class TranslationDataCollector extends DataCollector implements LateDataCollecto
 
     public function getFallbackLocales()
     {
-        return (isset($this->data['fallback_locales']) && count($this->data['fallback_locales']) > 0) ? $this->data['fallback_locales'] : array();
+        return (isset($this->data['fallback_locales']) && \count($this->data['fallback_locales']) > 0) ? $this->data['fallback_locales'] : array();
     }
 
     /**
@@ -158,7 +158,7 @@ class TranslationDataCollector extends DataCollector implements LateDataCollecto
             if (mb_strlen($string, $encoding) > $length) {
                 return mb_substr($string, 0, $length - 3, $encoding).'...';
             }
-        } elseif (strlen($string) > $length) {
+        } elseif (\strlen($string) > $length) {
             return substr($string, 0, $length - 3).'...';
         }
 
diff --git a/src/Symfony/Component/Translation/DataCollectorTranslator.php b/src/Symfony/Component/Translation/DataCollectorTranslator.php
index 715c390f53..5d4d819e0a 100644
--- a/src/Symfony/Component/Translation/DataCollectorTranslator.php
+++ b/src/Symfony/Component/Translation/DataCollectorTranslator.php
@@ -35,7 +35,7 @@ class DataCollectorTranslator implements TranslatorInterface, TranslatorBagInter
     public function __construct(TranslatorInterface $translator)
     {
         if (!$translator instanceof TranslatorBagInterface) {
-            throw new InvalidArgumentException(sprintf('The Translator "%s" must implement TranslatorInterface and TranslatorBagInterface.', get_class($translator)));
+            throw new InvalidArgumentException(sprintf('The Translator "%s" must implement TranslatorInterface and TranslatorBagInterface.', \get_class($translator)));
         }
 
         $this->translator = $translator;
@@ -106,7 +106,7 @@ class DataCollectorTranslator implements TranslatorInterface, TranslatorBagInter
      */
     public function __call($method, $args)
     {
-        return call_user_func_array(array($this->translator, $method), $args);
+        return \call_user_func_array(array($this->translator, $method), $args);
     }
 
     /**
diff --git a/src/Symfony/Component/Translation/Dumper/FileDumper.php b/src/Symfony/Component/Translation/Dumper/FileDumper.php
index 07c38b8291..0266af11d7 100644
--- a/src/Symfony/Component/Translation/Dumper/FileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/FileDumper.php
@@ -71,7 +71,7 @@ abstract class FileDumper implements DumperInterface
         foreach ($messages->getDomains() as $domain) {
             $fullpath = $options['path'].'/'.$this->getRelativePath($domain, $messages->getLocale());
             if (!file_exists($fullpath)) {
-                $directory = dirname($fullpath);
+                $directory = \dirname($fullpath);
                 if (!file_exists($directory) && !@mkdir($directory, 0777, true)) {
                     throw new RuntimeException(sprintf('Unable to create directory "%s".', $directory));
                 }
diff --git a/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php b/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
index 42f159501a..efa9d7fee6 100644
--- a/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
@@ -33,7 +33,7 @@ class IcuResFileDumper extends FileDumper
         $data = $indexes = $resources = '';
 
         foreach ($messages->all($domain) as $source => $target) {
-            $indexes .= pack('v', strlen($data) + 28);
+            $indexes .= pack('v', \strlen($data) + 28);
             $data .= $source."\0";
         }
 
@@ -44,7 +44,7 @@ class IcuResFileDumper extends FileDumper
         foreach ($messages->all($domain) as $source => $target) {
             $resources .= pack('V', $this->getPosition($data));
 
-            $data .= pack('V', strlen($target))
+            $data .= pack('V', \strlen($target))
                 .mb_convert_encoding($target."\0", 'UTF-16LE', 'UTF-8')
                 .$this->writePadding($data)
                   ;
@@ -52,7 +52,7 @@ class IcuResFileDumper extends FileDumper
 
         $resOffset = $this->getPosition($data);
 
-        $data .= pack('v', count($messages->all($domain)))
+        $data .= pack('v', \count($messages->all($domain)))
             .$indexes
             .$this->writePadding($data)
             .$resources
@@ -66,7 +66,7 @@ class IcuResFileDumper extends FileDumper
             $keyTop,                        // Index keys top
             $bundleTop,                     // Index resources top
             $bundleTop,                     // Index bundle top
-            count($messages->all($domain)), // Index max table length
+            \count($messages->all($domain)), // Index max table length
             0                               // Index attributes
         );
 
@@ -84,7 +84,7 @@ class IcuResFileDumper extends FileDumper
 
     private function writePadding($data)
     {
-        $padding = strlen($data) % 4;
+        $padding = \strlen($data) % 4;
 
         if ($padding) {
             return str_repeat("\xAA", 4 - $padding);
@@ -93,7 +93,7 @@ class IcuResFileDumper extends FileDumper
 
     private function getPosition($data)
     {
-        return (strlen($data) + 28) / 4;
+        return (\strlen($data) + 28) / 4;
     }
 
     /**
diff --git a/src/Symfony/Component/Translation/Dumper/MoFileDumper.php b/src/Symfony/Component/Translation/Dumper/MoFileDumper.php
index 00a33d253a..8a75151a4e 100644
--- a/src/Symfony/Component/Translation/Dumper/MoFileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/MoFileDumper.php
@@ -47,7 +47,7 @@ class MoFileDumper extends FileDumper
             'offsetHashes' => MoFileLoader::MO_HEADER_SIZE + (16 * $size),
         );
 
-        $sourcesSize = strlen($sources);
+        $sourcesSize = \strlen($sources);
         $sourcesStart = $header['offsetHashes'] + 1;
 
         foreach ($offsets as $offset) {
diff --git a/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php b/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php
index afeae3ac6e..48d8b39d02 100644
--- a/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/XliffFileDumper.php
@@ -147,7 +147,7 @@ class XliffFileDumper extends FileDumper
             $translation = $dom->createElement('unit');
             $translation->setAttribute('id', strtr(substr(base64_encode(hash('sha256', $source, true)), 0, 7), '/+', '._'));
             $name = $source;
-            if (strlen($source) > 80) {
+            if (\strlen($source) > 80) {
                 $name = substr(md5($source), -7);
             }
             $translation->setAttribute('name', $name);
@@ -200,6 +200,6 @@ class XliffFileDumper extends FileDumper
      */
     private function hasMetadataArrayInfo($key, $metadata = null)
     {
-        return null !== $metadata && array_key_exists($key, $metadata) && ($metadata[$key] instanceof \Traversable || is_array($metadata[$key]));
+        return null !== $metadata && array_key_exists($key, $metadata) && ($metadata[$key] instanceof \Traversable || \is_array($metadata[$key]));
     }
 }
diff --git a/src/Symfony/Component/Translation/Extractor/AbstractFileExtractor.php b/src/Symfony/Component/Translation/Extractor/AbstractFileExtractor.php
index bdfec1a9ed..bebd6d9162 100644
--- a/src/Symfony/Component/Translation/Extractor/AbstractFileExtractor.php
+++ b/src/Symfony/Component/Translation/Extractor/AbstractFileExtractor.php
@@ -27,7 +27,7 @@ abstract class AbstractFileExtractor
      */
     protected function extractFiles($resource)
     {
-        if (is_array($resource) || $resource instanceof \Traversable) {
+        if (\is_array($resource) || $resource instanceof \Traversable) {
             $files = array();
             foreach ($resource as $file) {
                 if ($this->canBeExtracted($file)) {
diff --git a/src/Symfony/Component/Translation/Extractor/PhpExtractor.php b/src/Symfony/Component/Translation/Extractor/PhpExtractor.php
index f364bdecd3..b4b32361ff 100644
--- a/src/Symfony/Component/Translation/Extractor/PhpExtractor.php
+++ b/src/Symfony/Component/Translation/Extractor/PhpExtractor.php
@@ -208,7 +208,7 @@ class PhpExtractor extends AbstractFileExtractor implements ExtractorInterface
                     } elseif (self::MESSAGE_TOKEN === $item) {
                         $message = $this->getValue($tokenIterator);
 
-                        if (count($sequence) === ($sequenceKey + 1)) {
+                        if (\count($sequence) === ($sequenceKey + 1)) {
                             break;
                         }
                     } elseif (self::METHOD_ARGUMENTS_TOKEN === $item) {
diff --git a/src/Symfony/Component/Translation/Extractor/PhpStringTokenParser.php b/src/Symfony/Component/Translation/Extractor/PhpStringTokenParser.php
index bab4ce0c97..6ed39d465f 100644
--- a/src/Symfony/Component/Translation/Extractor/PhpStringTokenParser.php
+++ b/src/Symfony/Component/Translation/Extractor/PhpStringTokenParser.php
@@ -113,9 +113,9 @@ class PhpStringTokenParser
         if (isset(self::$replacements[$str])) {
             return self::$replacements[$str];
         } elseif ('x' === $str[0] || 'X' === $str[0]) {
-            return chr(hexdec($str));
+            return \chr(hexdec($str));
         } else {
-            return chr(octdec($str));
+            return \chr(octdec($str));
         }
     }
 
diff --git a/src/Symfony/Component/Translation/Loader/ArrayLoader.php b/src/Symfony/Component/Translation/Loader/ArrayLoader.php
index 9a595b7dad..7bbfca68a4 100644
--- a/src/Symfony/Component/Translation/Loader/ArrayLoader.php
+++ b/src/Symfony/Component/Translation/Loader/ArrayLoader.php
@@ -52,7 +52,7 @@ class ArrayLoader implements LoaderInterface
             $subnode = &$messages;
         }
         foreach ($subnode as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 $nodePath = $path ? $path.'.'.$key : $key;
                 $this->flatten($messages, $value, $nodePath);
                 if (null === $path) {
diff --git a/src/Symfony/Component/Translation/Loader/CsvFileLoader.php b/src/Symfony/Component/Translation/Loader/CsvFileLoader.php
index e454d16922..8a763e725d 100644
--- a/src/Symfony/Component/Translation/Loader/CsvFileLoader.php
+++ b/src/Symfony/Component/Translation/Loader/CsvFileLoader.php
@@ -41,7 +41,7 @@ class CsvFileLoader extends FileLoader
         $file->setCsvControl($this->delimiter, $this->enclosure, $this->escape);
 
         foreach ($file as $data) {
-            if ('#' !== substr($data[0], 0, 1) && isset($data[1]) && 2 === count($data)) {
+            if ('#' !== substr($data[0], 0, 1) && isset($data[1]) && 2 === \count($data)) {
                 $messages[$data[0]] = $data[1];
             }
         }
diff --git a/src/Symfony/Component/Translation/Loader/FileLoader.php b/src/Symfony/Component/Translation/Loader/FileLoader.php
index 322679d24c..90a868263d 100644
--- a/src/Symfony/Component/Translation/Loader/FileLoader.php
+++ b/src/Symfony/Component/Translation/Loader/FileLoader.php
@@ -41,7 +41,7 @@ abstract class FileLoader extends ArrayLoader
         }
 
         // not an array
-        if (!is_array($messages)) {
+        if (!\is_array($messages)) {
             throw new InvalidResourceException(sprintf('Unable to load file "%s".', $resource));
         }
 
diff --git a/src/Symfony/Component/Translation/Loader/MoFileLoader.php b/src/Symfony/Component/Translation/Loader/MoFileLoader.php
index 918bf94a0a..a1d7c4aef5 100644
--- a/src/Symfony/Component/Translation/Loader/MoFileLoader.php
+++ b/src/Symfony/Component/Translation/Loader/MoFileLoader.php
@@ -111,7 +111,7 @@ class MoFileLoader extends FileLoader
             $ids = array('singular' => $singularId, 'plural' => $pluralId);
             $item = compact('ids', 'translated');
 
-            if (is_array($item['translated'])) {
+            if (\is_array($item['translated'])) {
                 $messages[$item['ids']['singular']] = stripcslashes($item['translated'][0]);
                 if (isset($item['ids']['plural'])) {
                     $plurals = array();
diff --git a/src/Symfony/Component/Translation/Loader/PoFileLoader.php b/src/Symfony/Component/Translation/Loader/PoFileLoader.php
index 7ce7d2dfff..066168dc71 100644
--- a/src/Symfony/Component/Translation/Loader/PoFileLoader.php
+++ b/src/Symfony/Component/Translation/Loader/PoFileLoader.php
@@ -78,7 +78,7 @@ class PoFileLoader extends FileLoader
 
             if ('' === $line) {
                 // Whitespace indicated current item is done
-                if (!in_array('fuzzy', $flags)) {
+                if (!\in_array('fuzzy', $flags)) {
                     $this->addMessage($messages, $item);
                 }
                 $item = $defaults;
@@ -96,7 +96,7 @@ class PoFileLoader extends FileLoader
             } elseif ('"' === $line[0]) {
                 $continues = isset($item['translated']) ? 'translated' : 'ids';
 
-                if (is_array($item[$continues])) {
+                if (\is_array($item[$continues])) {
                     end($item[$continues]);
                     $item[$continues][key($item[$continues])] .= substr($line, 1, -1);
                 } else {
@@ -110,7 +110,7 @@ class PoFileLoader extends FileLoader
             }
         }
         // save last item
-        if (!in_array('fuzzy', $flags)) {
+        if (!\in_array('fuzzy', $flags)) {
             $this->addMessage($messages, $item);
         }
         fclose($stream);
@@ -126,7 +126,7 @@ class PoFileLoader extends FileLoader
      */
     private function addMessage(array &$messages, array $item)
     {
-        if (is_array($item['translated'])) {
+        if (\is_array($item['translated'])) {
             $messages[stripcslashes($item['ids']['singular'])] = stripcslashes($item['translated'][0]);
             if (isset($item['ids']['plural'])) {
                 $plurals = $item['translated'];
diff --git a/src/Symfony/Component/Translation/LoggingTranslator.php b/src/Symfony/Component/Translation/LoggingTranslator.php
index 337c114330..0145670863 100644
--- a/src/Symfony/Component/Translation/LoggingTranslator.php
+++ b/src/Symfony/Component/Translation/LoggingTranslator.php
@@ -33,7 +33,7 @@ class LoggingTranslator implements TranslatorInterface, TranslatorBagInterface
     public function __construct(TranslatorInterface $translator, LoggerInterface $logger)
     {
         if (!$translator instanceof TranslatorBagInterface) {
-            throw new InvalidArgumentException(sprintf('The Translator "%s" must implement TranslatorInterface and TranslatorBagInterface.', get_class($translator)));
+            throw new InvalidArgumentException(sprintf('The Translator "%s" must implement TranslatorInterface and TranslatorBagInterface.', \get_class($translator)));
         }
 
         $this->translator = $translator;
@@ -105,7 +105,7 @@ class LoggingTranslator implements TranslatorInterface, TranslatorBagInterface
      */
     public function __call($method, $args)
     {
-        return call_user_func_array(array($this->translator, $method), $args);
+        return \call_user_func_array(array($this->translator, $method), $args);
     }
 
     /**
diff --git a/src/Symfony/Component/Translation/MessageSelector.php b/src/Symfony/Component/Translation/MessageSelector.php
index 31304cd0d8..5de171c5f4 100644
--- a/src/Symfony/Component/Translation/MessageSelector.php
+++ b/src/Symfony/Component/Translation/MessageSelector.php
@@ -82,7 +82,7 @@ class MessageSelector
         if (!isset($standardRules[$position])) {
             // when there's exactly one rule given, and that rule is a standard
             // rule, use this rule
-            if (1 === count($parts) && isset($standardRules[0])) {
+            if (1 === \count($parts) && isset($standardRules[0])) {
                 return $standardRules[0];
             }
 
diff --git a/src/Symfony/Component/Translation/PluralizationRules.php b/src/Symfony/Component/Translation/PluralizationRules.php
index 94d9e4350c..3aca0ba963 100644
--- a/src/Symfony/Component/Translation/PluralizationRules.php
+++ b/src/Symfony/Component/Translation/PluralizationRules.php
@@ -35,14 +35,14 @@ class PluralizationRules
             $locale = 'xbr';
         }
 
-        if (strlen($locale) > 3) {
-            $locale = substr($locale, 0, -strlen(strrchr($locale, '_')));
+        if (\strlen($locale) > 3) {
+            $locale = substr($locale, 0, -\strlen(strrchr($locale, '_')));
         }
 
         if (isset(self::$rules[$locale])) {
-            $return = call_user_func(self::$rules[$locale], $number);
+            $return = \call_user_func(self::$rules[$locale], $number);
 
-            if (!is_int($return) || $return < 0) {
+            if (!\is_int($return) || $return < 0) {
                 return 0;
             }
 
@@ -201,8 +201,8 @@ class PluralizationRules
             $locale = 'xbr';
         }
 
-        if (strlen($locale) > 3) {
-            $locale = substr($locale, 0, -strlen(strrchr($locale, '_')));
+        if (\strlen($locale) > 3) {
+            $locale = substr($locale, 0, -\strlen(strrchr($locale, '_')));
         }
 
         self::$rules[$locale] = $rule;
diff --git a/src/Symfony/Component/Translation/Reader/TranslationReader.php b/src/Symfony/Component/Translation/Reader/TranslationReader.php
index d2ad774e28..948edec492 100644
--- a/src/Symfony/Component/Translation/Reader/TranslationReader.php
+++ b/src/Symfony/Component/Translation/Reader/TranslationReader.php
@@ -55,7 +55,7 @@ class TranslationReader implements TranslationReaderInterface
             $extension = $catalogue->getLocale().'.'.$format;
             $files = $finder->files()->name('*.'.$extension)->in($directory);
             foreach ($files as $file) {
-                $domain = substr($file->getFilename(), 0, -1 * strlen($extension) - 1);
+                $domain = substr($file->getFilename(), 0, -1 * \strlen($extension) - 1);
                 $catalogue->addCatalogue($loader->load($file->getPathname(), $catalogue->getLocale(), $domain));
             }
         }
diff --git a/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationDumperPassTest.php b/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationDumperPassTest.php
index 3e02cb434e..759bb0e97d 100644
--- a/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationDumperPassTest.php
+++ b/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationDumperPassTest.php
@@ -35,8 +35,8 @@ class TranslationDumperPassTest extends TestCase
     {
         $container = new ContainerBuilder();
 
-        $definitionsBefore = count($container->getDefinitions());
-        $aliasesBefore = count($container->getAliases());
+        $definitionsBefore = \count($container->getDefinitions());
+        $aliasesBefore = \count($container->getAliases());
 
         $translationDumperPass = new TranslationDumperPass();
         $translationDumperPass->process($container);
diff --git a/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationExtractorPassTest.php b/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationExtractorPassTest.php
index b3313e63ee..14d164d0ee 100644
--- a/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationExtractorPassTest.php
+++ b/src/Symfony/Component/Translation/Tests/DependencyInjection/TranslationExtractorPassTest.php
@@ -35,8 +35,8 @@ class TranslationExtractorPassTest extends TestCase
     {
         $container = new ContainerBuilder();
 
-        $definitionsBefore = count($container->getDefinitions());
-        $aliasesBefore = count($container->getAliases());
+        $definitionsBefore = \count($container->getDefinitions());
+        $aliasesBefore = \count($container->getAliases());
 
         $translationDumperPass = new TranslationExtractorPass();
         $translationDumperPass->process($container);
diff --git a/src/Symfony/Component/Translation/Tests/Loader/LocalizedTestCase.php b/src/Symfony/Component/Translation/Tests/Loader/LocalizedTestCase.php
index a655c69d2e..279e9fde5b 100644
--- a/src/Symfony/Component/Translation/Tests/Loader/LocalizedTestCase.php
+++ b/src/Symfony/Component/Translation/Tests/Loader/LocalizedTestCase.php
@@ -17,7 +17,7 @@ abstract class LocalizedTestCase extends TestCase
 {
     protected function setUp()
     {
-        if (!extension_loaded('intl')) {
+        if (!\extension_loaded('intl')) {
             $this->markTestSkipped('Extension intl is required.');
         }
     }
diff --git a/src/Symfony/Component/Translation/Tests/PluralizationRulesTest.php b/src/Symfony/Component/Translation/Tests/PluralizationRulesTest.php
index a0624e297a..5eb6c01f5d 100644
--- a/src/Symfony/Component/Translation/Tests/PluralizationRulesTest.php
+++ b/src/Symfony/Component/Translation/Tests/PluralizationRulesTest.php
@@ -100,9 +100,9 @@ class PluralizationRulesTest extends TestCase
         foreach ($matrix as $langCode => $data) {
             $indexes = array_flip($data);
             if ($expectSuccess) {
-                $this->assertEquals($nplural, count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
+                $this->assertEquals($nplural, \count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
             } else {
-                $this->assertNotEquals((int) $nplural, count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
+                $this->assertNotEquals((int) $nplural, \count($indexes), "Langcode '$langCode' has '$nplural' plural forms.");
             }
         }
     }
diff --git a/src/Symfony/Component/Translation/Translator.php b/src/Symfony/Component/Translation/Translator.php
index 2899db0101..7891de9bfa 100644
--- a/src/Symfony/Component/Translation/Translator.php
+++ b/src/Symfony/Component/Translation/Translator.php
@@ -125,7 +125,7 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
 
         $this->resources[$locale][] = array($format, $resource, $domain);
 
-        if (in_array($locale, $this->fallbackLocales)) {
+        if (\in_array($locale, $this->fallbackLocales)) {
             $this->catalogues = array();
         } else {
             unset($this->catalogues[$locale]);
@@ -196,7 +196,7 @@ class Translator implements TranslatorInterface, TranslatorBagInterface
     public function transChoice($id, $number, array $parameters = array(), $domain = null, $locale = null)
     {
         if (!$this->formatter instanceof ChoiceMessageFormatterInterface) {
-            throw new LogicException(sprintf('The formatter "%s" does not support plural translations.', get_class($this->formatter)));
+            throw new LogicException(sprintf('The formatter "%s" does not support plural translations.', \get_class($this->formatter)));
         }
 
         if (null === $domain) {
@@ -402,7 +402,7 @@ EOF
         }
 
         if (false !== strrchr($locale, '_')) {
-            array_unshift($locales, substr($locale, 0, -strlen(strrchr($locale, '_'))));
+            array_unshift($locales, substr($locale, 0, -\strlen(strrchr($locale, '_'))));
         }
 
         return array_unique($locales);
diff --git a/src/Symfony/Component/Translation/Util/ArrayConverter.php b/src/Symfony/Component/Translation/Util/ArrayConverter.php
index 9c0a420a85..b98e7ce826 100644
--- a/src/Symfony/Component/Translation/Util/ArrayConverter.php
+++ b/src/Symfony/Component/Translation/Util/ArrayConverter.php
@@ -54,7 +54,7 @@ class ArrayConverter
         $parentOfElem = null;
 
         foreach ($parts as $i => $part) {
-            if (isset($elem[$part]) && is_string($elem[$part])) {
+            if (isset($elem[$part]) && \is_string($elem[$part])) {
                 /* Process next case:
                  *    'foo': 'test1',
                  *    'foo.bar': 'test2'
@@ -62,14 +62,14 @@ class ArrayConverter
                  * $tree['foo'] was string before we found array {bar: test2}.
                  *  Treat new element as string too, e.g. add $tree['foo.bar'] = 'test2';
                  */
-                $elem = &$elem[implode('.', array_slice($parts, $i))];
+                $elem = &$elem[implode('.', \array_slice($parts, $i))];
                 break;
             }
             $parentOfElem = &$elem;
             $elem = &$elem[$part];
         }
 
-        if (is_array($elem) && count($elem) > 0 && $parentOfElem) {
+        if (\is_array($elem) && \count($elem) > 0 && $parentOfElem) {
             /* Process next case:
              *    'foo.bar': 'test1'
              *    'foo': 'test2'
@@ -89,7 +89,7 @@ class ArrayConverter
         $prefix .= '.';
 
         foreach ($node as $id => $value) {
-            if (is_string($value)) {
+            if (\is_string($value)) {
                 $tree[$prefix.$id] = $value;
             } else {
                 self::cancelExpand($tree, $prefix.$id, $value);
diff --git a/src/Symfony/Component/Validator/Constraint.php b/src/Symfony/Component/Validator/Constraint.php
index c5890c658a..70a11ef8c9 100644
--- a/src/Symfony/Component/Validator/Constraint.php
+++ b/src/Symfony/Component/Validator/Constraint.php
@@ -73,7 +73,7 @@ abstract class Constraint
             throw new InvalidArgumentException(sprintf(
                 'The error code "%s" does not exist for constraint of type "%s".',
                 $errorCode,
-                get_called_class()
+                \get_called_class()
             ));
         }
 
@@ -116,15 +116,15 @@ abstract class Constraint
         // The "groups" option is added to the object lazily
         $knownOptions['groups'] = true;
 
-        if (is_array($options) && count($options) >= 1 && isset($options['value']) && !property_exists($this, 'value')) {
+        if (\is_array($options) && \count($options) >= 1 && isset($options['value']) && !property_exists($this, 'value')) {
             $options[$this->getDefaultOption()] = $options['value'];
             unset($options['value']);
         }
 
-        if (is_array($options)) {
+        if (\is_array($options)) {
             reset($options);
         }
-        if (is_array($options) && count($options) > 0 && is_string(key($options))) {
+        if (\is_array($options) && \count($options) > 0 && \is_string(key($options))) {
             foreach ($options as $option => $value) {
                 if (array_key_exists($option, $knownOptions)) {
                     $this->$option = $value;
@@ -133,12 +133,12 @@ abstract class Constraint
                     $invalidOptions[] = $option;
                 }
             }
-        } elseif (null !== $options && !(is_array($options) && 0 === count($options))) {
+        } elseif (null !== $options && !(\is_array($options) && 0 === \count($options))) {
             $option = $this->getDefaultOption();
 
             if (null === $option) {
                 throw new ConstraintDefinitionException(
-                    sprintf('No default option is configured for constraint %s', get_class($this))
+                    sprintf('No default option is configured for constraint %s', \get_class($this))
                 );
             }
 
@@ -150,16 +150,16 @@ abstract class Constraint
             }
         }
 
-        if (count($invalidOptions) > 0) {
+        if (\count($invalidOptions) > 0) {
             throw new InvalidOptionsException(
-                sprintf('The options "%s" do not exist in constraint %s', implode('", "', $invalidOptions), get_class($this)),
+                sprintf('The options "%s" do not exist in constraint %s', implode('", "', $invalidOptions), \get_class($this)),
                 $invalidOptions
             );
         }
 
-        if (count($missingOptions) > 0) {
+        if (\count($missingOptions) > 0) {
             throw new MissingOptionsException(
-                sprintf('The options "%s" must be set for constraint %s', implode('", "', array_keys($missingOptions)), get_class($this)),
+                sprintf('The options "%s" must be set for constraint %s', implode('", "', array_keys($missingOptions)), \get_class($this)),
                 array_keys($missingOptions)
             );
         }
@@ -185,7 +185,7 @@ abstract class Constraint
             return;
         }
 
-        throw new InvalidOptionsException(sprintf('The option "%s" does not exist in constraint %s', $option, get_class($this)), array($option));
+        throw new InvalidOptionsException(sprintf('The option "%s" does not exist in constraint %s', $option, \get_class($this)), array($option));
     }
 
     /**
@@ -211,7 +211,7 @@ abstract class Constraint
             return $this->groups;
         }
 
-        throw new InvalidOptionsException(sprintf('The option "%s" does not exist in constraint %s', $option, get_class($this)), array($option));
+        throw new InvalidOptionsException(sprintf('The option "%s" does not exist in constraint %s', $option, \get_class($this)), array($option));
     }
 
     /**
@@ -231,7 +231,7 @@ abstract class Constraint
      */
     public function addImplicitGroupName($group)
     {
-        if (in_array(self::DEFAULT_GROUP, $this->groups) && !in_array($group, $this->groups)) {
+        if (\in_array(self::DEFAULT_GROUP, $this->groups) && !\in_array($group, $this->groups)) {
             $this->groups[] = $group;
         }
     }
@@ -274,7 +274,7 @@ abstract class Constraint
      */
     public function validatedBy()
     {
-        return get_class($this).'Validator';
+        return \get_class($this).'Validator';
     }
 
     /**
diff --git a/src/Symfony/Component/Validator/ConstraintValidator.php b/src/Symfony/Component/Validator/ConstraintValidator.php
index 9a6b54a402..35f41889ea 100644
--- a/src/Symfony/Component/Validator/ConstraintValidator.php
+++ b/src/Symfony/Component/Validator/ConstraintValidator.php
@@ -58,7 +58,7 @@ abstract class ConstraintValidator implements ConstraintValidatorInterface
      */
     protected function formatTypeOf($value)
     {
-        return is_object($value) ? get_class($value) : gettype($value);
+        return \is_object($value) ? \get_class($value) : \gettype($value);
     }
 
     /**
@@ -107,7 +107,7 @@ abstract class ConstraintValidator implements ConstraintValidatorInterface
             return $value->format('Y-m-d H:i:s');
         }
 
-        if (is_object($value)) {
+        if (\is_object($value)) {
             if (($format & self::OBJECT_TO_STRING) && method_exists($value, '__toString')) {
                 return $value->__toString();
             }
@@ -115,15 +115,15 @@ abstract class ConstraintValidator implements ConstraintValidatorInterface
             return 'object';
         }
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             return 'array';
         }
 
-        if (is_string($value)) {
+        if (\is_string($value)) {
             return '"'.$value.'"';
         }
 
-        if (is_resource($value)) {
+        if (\is_resource($value)) {
             return 'resource';
         }
 
diff --git a/src/Symfony/Component/Validator/ConstraintViolation.php b/src/Symfony/Component/Validator/ConstraintViolation.php
index b3462e7d1c..57ece5ba37 100644
--- a/src/Symfony/Component/Validator/ConstraintViolation.php
+++ b/src/Symfony/Component/Validator/ConstraintViolation.php
@@ -70,9 +70,9 @@ class ConstraintViolation implements ConstraintViolationInterface
      */
     public function __toString()
     {
-        if (is_object($this->root)) {
-            $class = 'Object('.get_class($this->root).')';
-        } elseif (is_array($this->root)) {
+        if (\is_object($this->root)) {
+            $class = 'Object('.\get_class($this->root).')';
+        } elseif (\is_array($this->root)) {
             $class = 'Array';
         } else {
             $class = (string) $this->root;
diff --git a/src/Symfony/Component/Validator/ConstraintViolationList.php b/src/Symfony/Component/Validator/ConstraintViolationList.php
index a80d602b26..c18dd2195f 100644
--- a/src/Symfony/Component/Validator/ConstraintViolationList.php
+++ b/src/Symfony/Component/Validator/ConstraintViolationList.php
@@ -120,7 +120,7 @@ class ConstraintViolationList implements \IteratorAggregate, ConstraintViolation
      */
     public function count()
     {
-        return count($this->violations);
+        return \count($this->violations);
     }
 
     /**
@@ -171,7 +171,7 @@ class ConstraintViolationList implements \IteratorAggregate, ConstraintViolation
         $codes = (array) $codes;
         $violations = array();
         foreach ($this as $violation) {
-            if (in_array($violation->getCode(), $codes, true)) {
+            if (\in_array($violation->getCode(), $codes, true)) {
                 $violations[] = $violation;
             }
         }
diff --git a/src/Symfony/Component/Validator/Constraints/AbstractComparison.php b/src/Symfony/Component/Validator/Constraints/AbstractComparison.php
index c41f371e3a..0a7e2f3fb7 100644
--- a/src/Symfony/Component/Validator/Constraints/AbstractComparison.php
+++ b/src/Symfony/Component/Validator/Constraints/AbstractComparison.php
@@ -36,17 +36,17 @@ abstract class AbstractComparison extends Constraint
             $options = array();
         }
 
-        if (is_array($options)) {
+        if (\is_array($options)) {
             if (!isset($options['value']) && !isset($options['propertyPath'])) {
-                throw new ConstraintDefinitionException(sprintf('The "%s" constraint requires either the "value" or "propertyPath" option to be set.', get_class($this)));
+                throw new ConstraintDefinitionException(sprintf('The "%s" constraint requires either the "value" or "propertyPath" option to be set.', \get_class($this)));
             }
 
             if (isset($options['value']) && isset($options['propertyPath'])) {
-                throw new ConstraintDefinitionException(sprintf('The "%s" constraint requires only one of the "value" or "propertyPath" options to be set, not both.', get_class($this)));
+                throw new ConstraintDefinitionException(sprintf('The "%s" constraint requires only one of the "value" or "propertyPath" options to be set, not both.', \get_class($this)));
             }
 
             if (isset($options['propertyPath']) && !class_exists(PropertyAccess::class)) {
-                throw new ConstraintDefinitionException(sprintf('The "%s" constraint requires the Symfony PropertyAccess component to use the "propertyPath" option.', get_class($this)));
+                throw new ConstraintDefinitionException(sprintf('The "%s" constraint requires the Symfony PropertyAccess component to use the "propertyPath" option.', \get_class($this)));
             }
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/AbstractComparisonValidator.php b/src/Symfony/Component/Validator/Constraints/AbstractComparisonValidator.php
index ad3f4d2cbc..fec0080fe0 100644
--- a/src/Symfony/Component/Validator/Constraints/AbstractComparisonValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/AbstractComparisonValidator.php
@@ -55,7 +55,7 @@ abstract class AbstractComparisonValidator extends ConstraintValidator
             try {
                 $comparedValue = $this->getPropertyAccessor()->getValue($object, $path);
             } catch (NoSuchPropertyException $e) {
-                throw new ConstraintDefinitionException(sprintf('Invalid property path "%s" provided to "%s" constraint: %s', $path, get_class($constraint), $e->getMessage()), 0, $e);
+                throw new ConstraintDefinitionException(sprintf('Invalid property path "%s" provided to "%s" constraint: %s', $path, \get_class($constraint), $e->getMessage()), 0, $e);
             }
         } else {
             $comparedValue = $constraint->value;
@@ -65,7 +65,7 @@ abstract class AbstractComparisonValidator extends ConstraintValidator
         // This allows to compare with any date/time value supported by
         // the DateTime constructor:
         // http://php.net/manual/en/datetime.formats.php
-        if (is_string($comparedValue)) {
+        if (\is_string($comparedValue)) {
             if ($value instanceof \DateTimeImmutable) {
                 // If $value is immutable, convert the compared value to a
                 // DateTimeImmutable too
diff --git a/src/Symfony/Component/Validator/Constraints/AllValidator.php b/src/Symfony/Component/Validator/Constraints/AllValidator.php
index a5eb32bbd9..97de37058f 100644
--- a/src/Symfony/Component/Validator/Constraints/AllValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/AllValidator.php
@@ -33,7 +33,7 @@ class AllValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_array($value) && !$value instanceof \Traversable) {
+        if (!\is_array($value) && !$value instanceof \Traversable) {
             throw new UnexpectedTypeException($value, 'array or Traversable');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/BicValidator.php b/src/Symfony/Component/Validator/Constraints/BicValidator.php
index d2188071fa..51aecc384a 100644
--- a/src/Symfony/Component/Validator/Constraints/BicValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/BicValidator.php
@@ -33,7 +33,7 @@ class BicValidator extends ConstraintValidator
         $canonicalize = str_replace(' ', '', $value);
 
         // the bic must be either 8 or 11 characters long
-        if (!in_array(strlen($canonicalize), array(8, 11))) {
+        if (!\in_array(\strlen($canonicalize), array(8, 11))) {
             $this->context->buildViolation($constraint->message)
                 ->setParameter('{{ value }}', $this->formatValue($value))
                 ->setCode(Bic::INVALID_LENGTH_ERROR)
diff --git a/src/Symfony/Component/Validator/Constraints/Callback.php b/src/Symfony/Component/Validator/Constraints/Callback.php
index 4a43665b0d..16231105e1 100644
--- a/src/Symfony/Component/Validator/Constraints/Callback.php
+++ b/src/Symfony/Component/Validator/Constraints/Callback.php
@@ -32,11 +32,11 @@ class Callback extends Constraint
     public function __construct($options = null)
     {
         // Invocation through annotations with an array parameter only
-        if (is_array($options) && 1 === count($options) && isset($options['value'])) {
+        if (\is_array($options) && 1 === \count($options) && isset($options['value'])) {
             $options = $options['value'];
         }
 
-        if (is_array($options) && !isset($options['callback']) && !isset($options['groups']) && !isset($options['payload'])) {
+        if (\is_array($options) && !isset($options['callback']) && !isset($options['groups']) && !isset($options['payload'])) {
             $options = array('callback' => $options);
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/CallbackValidator.php b/src/Symfony/Component/Validator/Constraints/CallbackValidator.php
index 733ee43ba7..a66840eae1 100644
--- a/src/Symfony/Component/Validator/Constraints/CallbackValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/CallbackValidator.php
@@ -35,18 +35,18 @@ class CallbackValidator extends ConstraintValidator
         $method = $constraint->callback;
         if ($method instanceof \Closure) {
             $method($object, $this->context, $constraint->payload);
-        } elseif (is_array($method)) {
-            if (!is_callable($method)) {
-                if (isset($method[0]) && is_object($method[0])) {
-                    $method[0] = get_class($method[0]);
+        } elseif (\is_array($method)) {
+            if (!\is_callable($method)) {
+                if (isset($method[0]) && \is_object($method[0])) {
+                    $method[0] = \get_class($method[0]);
                 }
                 throw new ConstraintDefinitionException(sprintf('%s targeted by Callback constraint is not a valid callable', json_encode($method)));
             }
 
-            call_user_func($method, $object, $this->context, $constraint->payload);
+            \call_user_func($method, $object, $this->context, $constraint->payload);
         } elseif (null !== $object) {
             if (!method_exists($object, $method)) {
-                throw new ConstraintDefinitionException(sprintf('Method "%s" targeted by Callback constraint does not exist in class %s', $method, get_class($object)));
+                throw new ConstraintDefinitionException(sprintf('Method "%s" targeted by Callback constraint does not exist in class %s', $method, \get_class($object)));
             }
 
             $reflMethod = new \ReflectionMethod($object, $method);
diff --git a/src/Symfony/Component/Validator/Constraints/ChoiceValidator.php b/src/Symfony/Component/Validator/Constraints/ChoiceValidator.php
index 2dc5b182ff..e40b4d9ecf 100644
--- a/src/Symfony/Component/Validator/Constraints/ChoiceValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/ChoiceValidator.php
@@ -34,7 +34,7 @@ class ChoiceValidator extends ConstraintValidator
             throw new UnexpectedTypeException($constraint, __NAMESPACE__.'\Choice');
         }
 
-        if (!is_array($constraint->choices) && !$constraint->callback) {
+        if (!\is_array($constraint->choices) && !$constraint->callback) {
             throw new ConstraintDefinitionException('Either "choices" or "callback" must be specified on constraint Choice');
         }
 
@@ -42,18 +42,18 @@ class ChoiceValidator extends ConstraintValidator
             return;
         }
 
-        if ($constraint->multiple && !is_array($value)) {
+        if ($constraint->multiple && !\is_array($value)) {
             throw new UnexpectedTypeException($value, 'array');
         }
 
         if ($constraint->callback) {
-            if (!is_callable($choices = array($this->context->getObject(), $constraint->callback))
-                && !is_callable($choices = array($this->context->getClassName(), $constraint->callback))
-                && !is_callable($choices = $constraint->callback)
+            if (!\is_callable($choices = array($this->context->getObject(), $constraint->callback))
+                && !\is_callable($choices = array($this->context->getClassName(), $constraint->callback))
+                && !\is_callable($choices = $constraint->callback)
             ) {
                 throw new ConstraintDefinitionException('The Choice constraint expects a valid callback');
             }
-            $choices = call_user_func($choices);
+            $choices = \call_user_func($choices);
         } else {
             $choices = $constraint->choices;
         }
@@ -64,7 +64,7 @@ class ChoiceValidator extends ConstraintValidator
 
         if ($constraint->multiple) {
             foreach ($value as $_value) {
-                if (!in_array($_value, $choices, true)) {
+                if (!\in_array($_value, $choices, true)) {
                     $this->context->buildViolation($constraint->multipleMessage)
                         ->setParameter('{{ value }}', $this->formatValue($_value))
                         ->setCode(Choice::NO_SUCH_CHOICE_ERROR)
@@ -75,7 +75,7 @@ class ChoiceValidator extends ConstraintValidator
                 }
             }
 
-            $count = count($value);
+            $count = \count($value);
 
             if (null !== $constraint->min && $count < $constraint->min) {
                 $this->context->buildViolation($constraint->minMessage)
@@ -96,7 +96,7 @@ class ChoiceValidator extends ConstraintValidator
 
                 return;
             }
-        } elseif (!in_array($value, $choices, true)) {
+        } elseif (!\in_array($value, $choices, true)) {
             $this->context->buildViolation($constraint->message)
                 ->setParameter('{{ value }}', $this->formatValue($value))
                 ->setCode(Choice::NO_SUCH_CHOICE_ERROR)
diff --git a/src/Symfony/Component/Validator/Constraints/Collection.php b/src/Symfony/Component/Validator/Constraints/Collection.php
index 9cb2063042..2b5679b22d 100644
--- a/src/Symfony/Component/Validator/Constraints/Collection.php
+++ b/src/Symfony/Component/Validator/Constraints/Collection.php
@@ -41,7 +41,7 @@ class Collection extends Composite
     public function __construct($options = null)
     {
         // no known options set? $options is the fields array
-        if (is_array($options)
+        if (\is_array($options)
             && !array_intersect(array_keys($options), array('groups', 'fields', 'allowExtraFields', 'allowMissingFields', 'extraFieldsMessage', 'missingFieldsMessage'))) {
             $options = array('fields' => $options);
         }
@@ -56,14 +56,14 @@ class Collection extends Composite
     {
         parent::initializeNestedConstraints();
 
-        if (!is_array($this->fields)) {
+        if (!\is_array($this->fields)) {
             throw new ConstraintDefinitionException(sprintf('The option "fields" is expected to be an array in constraint %s', __CLASS__));
         }
 
         foreach ($this->fields as $fieldName => $field) {
             // the XmlFileLoader and YamlFileLoader pass the field Optional
             // and Required constraint as an array with exactly one element
-            if (is_array($field) && 1 == count($field)) {
+            if (\is_array($field) && 1 == \count($field)) {
                 $this->fields[$fieldName] = $field = $field[0];
             }
 
diff --git a/src/Symfony/Component/Validator/Constraints/CollectionValidator.php b/src/Symfony/Component/Validator/Constraints/CollectionValidator.php
index f4a6d19ec7..e3a297329d 100644
--- a/src/Symfony/Component/Validator/Constraints/CollectionValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/CollectionValidator.php
@@ -33,7 +33,7 @@ class CollectionValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_array($value) && !($value instanceof \Traversable && $value instanceof \ArrayAccess)) {
+        if (!\is_array($value) && !($value instanceof \Traversable && $value instanceof \ArrayAccess)) {
             throw new UnexpectedTypeException($value, 'array or Traversable and ArrayAccess');
         }
 
@@ -50,11 +50,11 @@ class CollectionValidator extends ConstraintValidator
 
         foreach ($constraint->fields as $field => $fieldConstraint) {
             // bug fix issue #2779
-            $existsInArray = is_array($value) && array_key_exists($field, $value);
+            $existsInArray = \is_array($value) && array_key_exists($field, $value);
             $existsInArrayAccess = $value instanceof \ArrayAccess && $value->offsetExists($field);
 
             if ($existsInArray || $existsInArrayAccess) {
-                if (count($fieldConstraint->constraints) > 0) {
+                if (\count($fieldConstraint->constraints) > 0) {
                     $context->getValidator()
                         ->inContext($context)
                         ->atPath('['.$field.']')
diff --git a/src/Symfony/Component/Validator/Constraints/Composite.php b/src/Symfony/Component/Validator/Constraints/Composite.php
index d1391bb072..2f2b8d29a0 100644
--- a/src/Symfony/Component/Validator/Constraints/Composite.php
+++ b/src/Symfony/Component/Validator/Constraints/Composite.php
@@ -61,21 +61,21 @@ abstract class Composite extends Constraint
         $compositeOption = $this->getCompositeOption();
         $nestedConstraints = $this->$compositeOption;
 
-        if (!is_array($nestedConstraints)) {
+        if (!\is_array($nestedConstraints)) {
             $nestedConstraints = array($nestedConstraints);
         }
 
         foreach ($nestedConstraints as $constraint) {
             if (!$constraint instanceof Constraint) {
-                if (is_object($constraint)) {
-                    $constraint = get_class($constraint);
+                if (\is_object($constraint)) {
+                    $constraint = \get_class($constraint);
                 }
 
-                throw new ConstraintDefinitionException(sprintf('The value %s is not an instance of Constraint in constraint %s', $constraint, get_class($this)));
+                throw new ConstraintDefinitionException(sprintf('The value %s is not an instance of Constraint in constraint %s', $constraint, \get_class($this)));
             }
 
             if ($constraint instanceof Valid) {
-                throw new ConstraintDefinitionException(sprintf('The constraint Valid cannot be nested inside constraint %s. You can only declare the Valid constraint directly on a field or method.', get_class($this)));
+                throw new ConstraintDefinitionException(sprintf('The constraint Valid cannot be nested inside constraint %s. You can only declare the Valid constraint directly on a field or method.', \get_class($this)));
             }
         }
 
@@ -98,13 +98,13 @@ abstract class Composite extends Constraint
             if (property_exists($constraint, 'groups')) {
                 $excessGroups = array_diff($constraint->groups, $this->groups);
 
-                if (count($excessGroups) > 0) {
+                if (\count($excessGroups) > 0) {
                     throw new ConstraintDefinitionException(sprintf(
                         'The group(s) "%s" passed to the constraint %s '.
                         'should also be passed to its containing constraint %s',
                         implode('", "', $excessGroups),
-                        get_class($constraint),
-                        get_class($this)
+                        \get_class($constraint),
+                        \get_class($this)
                     ));
                 }
             } else {
diff --git a/src/Symfony/Component/Validator/Constraints/Count.php b/src/Symfony/Component/Validator/Constraints/Count.php
index 53870fb597..0a54ee78db 100644
--- a/src/Symfony/Component/Validator/Constraints/Count.php
+++ b/src/Symfony/Component/Validator/Constraints/Count.php
@@ -38,7 +38,7 @@ class Count extends Constraint
 
     public function __construct($options = null)
     {
-        if (null !== $options && !is_array($options)) {
+        if (null !== $options && !\is_array($options)) {
             $options = array(
                 'min' => $options,
                 'max' => $options,
diff --git a/src/Symfony/Component/Validator/Constraints/CountValidator.php b/src/Symfony/Component/Validator/Constraints/CountValidator.php
index 69c8257206..39be8aa82e 100644
--- a/src/Symfony/Component/Validator/Constraints/CountValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/CountValidator.php
@@ -29,11 +29,11 @@ class CountValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_array($value) && !$value instanceof \Countable) {
+        if (!\is_array($value) && !$value instanceof \Countable) {
             throw new UnexpectedTypeException($value, 'array or \Countable');
         }
 
-        $count = count($value);
+        $count = \count($value);
 
         if (null !== $constraint->max && $count > $constraint->max) {
             $this->context->buildViolation($constraint->min == $constraint->max ? $constraint->exactMessage : $constraint->maxMessage)
diff --git a/src/Symfony/Component/Validator/Constraints/CountryValidator.php b/src/Symfony/Component/Validator/Constraints/CountryValidator.php
index 3cea3b7384..46585da8b9 100644
--- a/src/Symfony/Component/Validator/Constraints/CountryValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/CountryValidator.php
@@ -36,7 +36,7 @@ class CountryValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/CurrencyValidator.php b/src/Symfony/Component/Validator/Constraints/CurrencyValidator.php
index a110bec605..42fa8cfa45 100644
--- a/src/Symfony/Component/Validator/Constraints/CurrencyValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/CurrencyValidator.php
@@ -37,7 +37,7 @@ class CurrencyValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php b/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php
index 63c6a7b903..6ed25a3dfc 100644
--- a/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/DateTimeValidator.php
@@ -33,7 +33,7 @@ class DateTimeValidator extends DateValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/DateValidator.php b/src/Symfony/Component/Validator/Constraints/DateValidator.php
index ed836de9ac..a1492c54c9 100644
--- a/src/Symfony/Component/Validator/Constraints/DateValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/DateValidator.php
@@ -51,7 +51,7 @@ class DateValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/Email.php b/src/Symfony/Component/Validator/Constraints/Email.php
index dbff1d4cc4..ba588a4c1c 100644
--- a/src/Symfony/Component/Validator/Constraints/Email.php
+++ b/src/Symfony/Component/Validator/Constraints/Email.php
@@ -58,11 +58,11 @@ class Email extends Constraint
 
     public function __construct($options = null)
     {
-        if (is_array($options) && array_key_exists('strict', $options)) {
+        if (\is_array($options) && array_key_exists('strict', $options)) {
             @trigger_error(sprintf('The "strict" property is deprecated since Symfony 4.1. Use "mode"=>"%s" instead.', self::VALIDATION_MODE_STRICT), E_USER_DEPRECATED);
         }
 
-        if (is_array($options) && array_key_exists('mode', $options) && !in_array($options['mode'], self::$validationModes, true)) {
+        if (\is_array($options) && array_key_exists('mode', $options) && !\in_array($options['mode'], self::$validationModes, true)) {
             throw new \InvalidArgumentException('The "mode" parameter value is not valid.');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/EmailValidator.php b/src/Symfony/Component/Validator/Constraints/EmailValidator.php
index 0b7112c50b..15bb8dda13 100644
--- a/src/Symfony/Component/Validator/Constraints/EmailValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/EmailValidator.php
@@ -48,13 +48,13 @@ class EmailValidator extends ConstraintValidator
      */
     public function __construct($defaultMode = Email::VALIDATION_MODE_LOOSE)
     {
-        if (is_bool($defaultMode)) {
+        if (\is_bool($defaultMode)) {
             @trigger_error(sprintf('Calling `new %s(%s)` is deprecated since Symfony 4.1, use `new %s("%s")` instead.', self::class, $defaultMode ? 'true' : 'false', self::class, $defaultMode ? Email::VALIDATION_MODE_STRICT : Email::VALIDATION_MODE_LOOSE), E_USER_DEPRECATED);
 
             $defaultMode = $defaultMode ? Email::VALIDATION_MODE_STRICT : Email::VALIDATION_MODE_LOOSE;
         }
 
-        if (!in_array($defaultMode, Email::$validationModes, true)) {
+        if (!\in_array($defaultMode, Email::$validationModes, true)) {
             throw new \InvalidArgumentException('The "defaultMode" parameter value is not valid.');
         }
 
@@ -74,7 +74,7 @@ class EmailValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -94,8 +94,8 @@ class EmailValidator extends ConstraintValidator
             $constraint->mode = $this->defaultMode;
         }
 
-        if (!in_array($constraint->mode, Email::$validationModes, true)) {
-            throw new \InvalidArgumentException(sprintf('The %s::$mode parameter value is not valid.', get_class($constraint)));
+        if (!\in_array($constraint->mode, Email::$validationModes, true)) {
+            throw new \InvalidArgumentException(sprintf('The %s::$mode parameter value is not valid.', \get_class($constraint)));
         }
 
         if (Email::VALIDATION_MODE_STRICT === $constraint->mode) {
diff --git a/src/Symfony/Component/Validator/Constraints/File.php b/src/Symfony/Component/Validator/Constraints/File.php
index ff2627b38e..33215bb7b5 100644
--- a/src/Symfony/Component/Validator/Constraints/File.php
+++ b/src/Symfony/Component/Validator/Constraints/File.php
@@ -113,7 +113,7 @@ class File extends Constraint
             $this->binaryFormat = null === $this->binaryFormat ? false : $this->binaryFormat;
         } elseif (preg_match('/^(\d++)('.implode('|', array_keys($factors)).')$/i', $maxSize, $matches)) {
             $this->maxSize = $matches[1] * $factors[$unit = strtolower($matches[2])];
-            $this->binaryFormat = null === $this->binaryFormat ? 2 === strlen($unit) : $this->binaryFormat;
+            $this->binaryFormat = null === $this->binaryFormat ? 2 === \strlen($unit) : $this->binaryFormat;
         } else {
             throw new ConstraintDefinitionException(sprintf('"%s" is not a valid maximum size', $this->maxSize));
         }
diff --git a/src/Symfony/Component/Validator/Constraints/FileValidator.php b/src/Symfony/Component/Validator/Constraints/FileValidator.php
index e752f2a1e6..e59f25247e 100644
--- a/src/Symfony/Component/Validator/Constraints/FileValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/FileValidator.php
@@ -113,7 +113,7 @@ class FileValidator extends ConstraintValidator
             }
         }
 
-        if (!is_scalar($value) && !$value instanceof FileObject && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !$value instanceof FileObject && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -196,7 +196,7 @@ class FileValidator extends ConstraintValidator
 
     private static function moreDecimalsThan($double, $numberOfDecimals)
     {
-        return strlen((string) $double) > strlen(round($double, $numberOfDecimals));
+        return \strlen((string) $double) > \strlen(round($double, $numberOfDecimals));
     }
 
     /**
diff --git a/src/Symfony/Component/Validator/Constraints/IbanValidator.php b/src/Symfony/Component/Validator/Constraints/IbanValidator.php
index 3b4fcc02d3..9d8d5b863c 100644
--- a/src/Symfony/Component/Validator/Constraints/IbanValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/IbanValidator.php
@@ -148,7 +148,7 @@ class IbanValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -231,7 +231,7 @@ class IbanValidator extends ConstraintValidator
         foreach ($chars as $char) {
             // Convert uppercase characters to ordinals, starting with 10 for "A"
             if (ctype_upper($char)) {
-                $bigInt .= (ord($char) - 55);
+                $bigInt .= (\ord($char) - 55);
 
                 continue;
             }
diff --git a/src/Symfony/Component/Validator/Constraints/ImageValidator.php b/src/Symfony/Component/Validator/Constraints/ImageValidator.php
index 0b3122bbc4..4b6a6f3b20 100644
--- a/src/Symfony/Component/Validator/Constraints/ImageValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/ImageValidator.php
@@ -34,11 +34,11 @@ class ImageValidator extends FileValidator
             throw new UnexpectedTypeException($constraint, __NAMESPACE__.'\Image');
         }
 
-        $violations = count($this->context->getViolations());
+        $violations = \count($this->context->getViolations());
 
         parent::validate($value, $constraint);
 
-        $failed = count($this->context->getViolations()) !== $violations;
+        $failed = \count($this->context->getViolations()) !== $violations;
 
         if ($failed || null === $value || '' === $value) {
             return;
@@ -217,7 +217,7 @@ class ImageValidator extends FileValidator
         }
 
         if ($constraint->detectCorrupted) {
-            if (!function_exists('imagecreatefromstring')) {
+            if (!\function_exists('imagecreatefromstring')) {
                 throw new RuntimeException('Corrupted images detection requires installed and enabled GD extension');
             }
 
diff --git a/src/Symfony/Component/Validator/Constraints/Ip.php b/src/Symfony/Component/Validator/Constraints/Ip.php
index 36772c62aa..f45c4caceb 100644
--- a/src/Symfony/Component/Validator/Constraints/Ip.php
+++ b/src/Symfony/Component/Validator/Constraints/Ip.php
@@ -79,7 +79,7 @@ class Ip extends Constraint
     {
         parent::__construct($options);
 
-        if (!in_array($this->version, self::$versions)) {
+        if (!\in_array($this->version, self::$versions)) {
             throw new ConstraintDefinitionException(sprintf('The option "version" must be one of "%s"', implode('", "', self::$versions)));
         }
     }
diff --git a/src/Symfony/Component/Validator/Constraints/IpValidator.php b/src/Symfony/Component/Validator/Constraints/IpValidator.php
index 7f806bf7fc..5c687b900f 100644
--- a/src/Symfony/Component/Validator/Constraints/IpValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/IpValidator.php
@@ -36,7 +36,7 @@ class IpValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/IsbnValidator.php b/src/Symfony/Component/Validator/Constraints/IsbnValidator.php
index 2e342673d3..9f0d1fa1a3 100644
--- a/src/Symfony/Component/Validator/Constraints/IsbnValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/IsbnValidator.php
@@ -39,7 +39,7 @@ class IsbnValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -145,7 +145,7 @@ class IsbnValidator extends ConstraintValidator
             return Isbn::INVALID_CHARACTERS_ERROR;
         }
 
-        $length = strlen($isbn);
+        $length = \strlen($isbn);
 
         if ($length < 13) {
             return Isbn::TOO_SHORT_ERROR;
diff --git a/src/Symfony/Component/Validator/Constraints/IssnValidator.php b/src/Symfony/Component/Validator/Constraints/IssnValidator.php
index ae1bb6fa34..f045e62e2c 100644
--- a/src/Symfony/Component/Validator/Constraints/IssnValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/IssnValidator.php
@@ -38,7 +38,7 @@ class IssnValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -59,7 +59,7 @@ class IssnValidator extends ConstraintValidator
             return;
         }
 
-        $length = strlen($canonical);
+        $length = \strlen($canonical);
 
         if ($length < 8) {
             $this->context->buildViolation($constraint->message)
diff --git a/src/Symfony/Component/Validator/Constraints/LanguageValidator.php b/src/Symfony/Component/Validator/Constraints/LanguageValidator.php
index c0bc08fdd7..1722034720 100644
--- a/src/Symfony/Component/Validator/Constraints/LanguageValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/LanguageValidator.php
@@ -36,7 +36,7 @@ class LanguageValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/Length.php b/src/Symfony/Component/Validator/Constraints/Length.php
index 0f965089b5..20a17fabca 100644
--- a/src/Symfony/Component/Validator/Constraints/Length.php
+++ b/src/Symfony/Component/Validator/Constraints/Length.php
@@ -42,7 +42,7 @@ class Length extends Constraint
 
     public function __construct($options = null)
     {
-        if (null !== $options && !is_array($options)) {
+        if (null !== $options && !\is_array($options)) {
             $options = array(
                 'min' => $options,
                 'max' => $options,
diff --git a/src/Symfony/Component/Validator/Constraints/LengthValidator.php b/src/Symfony/Component/Validator/Constraints/LengthValidator.php
index 490f5a36aa..d8cb09ccb6 100644
--- a/src/Symfony/Component/Validator/Constraints/LengthValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/LengthValidator.php
@@ -33,7 +33,7 @@ class LengthValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/LocaleValidator.php b/src/Symfony/Component/Validator/Constraints/LocaleValidator.php
index 66421ecad4..cc23b3f1a4 100644
--- a/src/Symfony/Component/Validator/Constraints/LocaleValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/LocaleValidator.php
@@ -36,7 +36,7 @@ class LocaleValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -48,7 +48,7 @@ class LocaleValidator extends ConstraintValidator
         $localeBundle = Intl::getLocaleBundle();
         $locales = $localeBundle->getLocaleNames();
 
-        if (!isset($locales[$value]) && !in_array($value, $localeBundle->getAliases(), true)) {
+        if (!isset($locales[$value]) && !\in_array($value, $localeBundle->getAliases(), true)) {
             $this->context->buildViolation($constraint->message)
                 ->setParameter('{{ value }}', $this->formatValue($inputValue))
                 ->setCode(Locale::NO_SUCH_LOCALE_ERROR)
diff --git a/src/Symfony/Component/Validator/Constraints/LuhnValidator.php b/src/Symfony/Component/Validator/Constraints/LuhnValidator.php
index 85e4d76215..554fc6f48b 100644
--- a/src/Symfony/Component/Validator/Constraints/LuhnValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/LuhnValidator.php
@@ -49,7 +49,7 @@ class LuhnValidator extends ConstraintValidator
 
         // Work with strings only, because long numbers are represented as floats
         // internally and don't work with strlen()
-        if (!is_string($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!\is_string($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -65,7 +65,7 @@ class LuhnValidator extends ConstraintValidator
         }
 
         $checkSum = 0;
-        $length = strlen($value);
+        $length = \strlen($value);
 
         // Starting with the last digit and walking left, add every second
         // digit to the check sum
diff --git a/src/Symfony/Component/Validator/Constraints/RangeValidator.php b/src/Symfony/Component/Validator/Constraints/RangeValidator.php
index ac140dbbf3..e0cb92a93e 100644
--- a/src/Symfony/Component/Validator/Constraints/RangeValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/RangeValidator.php
@@ -50,11 +50,11 @@ class RangeValidator extends ConstraintValidator
         // the DateTime constructor:
         // http://php.net/manual/en/datetime.formats.php
         if ($value instanceof \DateTimeInterface) {
-            if (is_string($min)) {
+            if (\is_string($min)) {
                 $min = new \DateTime($min);
             }
 
-            if (is_string($max)) {
+            if (\is_string($max)) {
                 $max = new \DateTime($max);
             }
         }
diff --git a/src/Symfony/Component/Validator/Constraints/Regex.php b/src/Symfony/Component/Validator/Constraints/Regex.php
index 7a43667fef..cb12210225 100644
--- a/src/Symfony/Component/Validator/Constraints/Regex.php
+++ b/src/Symfony/Component/Validator/Constraints/Regex.php
@@ -70,7 +70,7 @@ class Regex extends Constraint
         }
 
         // Quit if delimiters not at very beginning/end (e.g. when options are passed)
-        if ($this->pattern[0] !== $this->pattern[strlen($this->pattern) - 1]) {
+        if ($this->pattern[0] !== $this->pattern[\strlen($this->pattern) - 1]) {
             return;
         }
 
@@ -95,7 +95,7 @@ class Regex extends Constraint
         $pattern = '^' === $pattern[0] ? substr($pattern, 1) : '.*'.$pattern;
 
         // Trim trailing $, otherwise append .*
-        $pattern = '$' === $pattern[strlen($pattern) - 1] ? substr($pattern, 0, -1) : $pattern.'.*';
+        $pattern = '$' === $pattern[\strlen($pattern) - 1] ? substr($pattern, 0, -1) : $pattern.'.*';
 
         return $pattern;
     }
diff --git a/src/Symfony/Component/Validator/Constraints/RegexValidator.php b/src/Symfony/Component/Validator/Constraints/RegexValidator.php
index 48ee61a74e..c6b70feb7f 100644
--- a/src/Symfony/Component/Validator/Constraints/RegexValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/RegexValidator.php
@@ -36,7 +36,7 @@ class RegexValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/TimeValidator.php b/src/Symfony/Component/Validator/Constraints/TimeValidator.php
index 3f0234b8b0..b1ee40c530 100644
--- a/src/Symfony/Component/Validator/Constraints/TimeValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/TimeValidator.php
@@ -51,7 +51,7 @@ class TimeValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
diff --git a/src/Symfony/Component/Validator/Constraints/Traverse.php b/src/Symfony/Component/Validator/Constraints/Traverse.php
index 9d8bc126d1..0b74d98d46 100644
--- a/src/Symfony/Component/Validator/Constraints/Traverse.php
+++ b/src/Symfony/Component/Validator/Constraints/Traverse.php
@@ -25,7 +25,7 @@ class Traverse extends Constraint
 
     public function __construct($options = null)
     {
-        if (is_array($options) && array_key_exists('groups', $options)) {
+        if (\is_array($options) && array_key_exists('groups', $options)) {
             throw new ConstraintDefinitionException(sprintf(
                 'The option "groups" is not supported by the constraint %s',
                 __CLASS__
diff --git a/src/Symfony/Component/Validator/Constraints/TypeValidator.php b/src/Symfony/Component/Validator/Constraints/TypeValidator.php
index ea7562bfcf..206836d361 100644
--- a/src/Symfony/Component/Validator/Constraints/TypeValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/TypeValidator.php
@@ -38,9 +38,9 @@ class TypeValidator extends ConstraintValidator
         $isFunction = 'is_'.$type;
         $ctypeFunction = 'ctype_'.$type;
 
-        if (function_exists($isFunction) && $isFunction($value)) {
+        if (\function_exists($isFunction) && $isFunction($value)) {
             return;
-        } elseif (function_exists($ctypeFunction) && $ctypeFunction($value)) {
+        } elseif (\function_exists($ctypeFunction) && $ctypeFunction($value)) {
             return;
         } elseif ($value instanceof $constraint->type) {
             return;
diff --git a/src/Symfony/Component/Validator/Constraints/Url.php b/src/Symfony/Component/Validator/Constraints/Url.php
index f5ca253409..abedcf29d9 100644
--- a/src/Symfony/Component/Validator/Constraints/Url.php
+++ b/src/Symfony/Component/Validator/Constraints/Url.php
@@ -108,7 +108,7 @@ class Url extends Constraint
 
     public function __construct($options = null)
     {
-        if (is_array($options)) {
+        if (\is_array($options)) {
             if (array_key_exists('checkDNS', $options)) {
                 @trigger_error(sprintf('The "checkDNS" option in "%s" is deprecated since Symfony 4.1. Its false-positive rate is too high to be relied upon.', self::class), E_USER_DEPRECATED);
             }
diff --git a/src/Symfony/Component/Validator/Constraints/UrlValidator.php b/src/Symfony/Component/Validator/Constraints/UrlValidator.php
index e7b3a3b570..35c63a06dc 100644
--- a/src/Symfony/Component/Validator/Constraints/UrlValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/UrlValidator.php
@@ -52,7 +52,7 @@ class UrlValidator extends ConstraintValidator
             return;
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -74,7 +74,7 @@ class UrlValidator extends ConstraintValidator
         }
 
         if ($constraint->checkDNS) {
-            if (!in_array($constraint->checkDNS, array(
+            if (!\in_array($constraint->checkDNS, array(
                 Url::CHECK_DNS_TYPE_ANY,
                 Url::CHECK_DNS_TYPE_A,
                 Url::CHECK_DNS_TYPE_A6,
@@ -88,12 +88,12 @@ class UrlValidator extends ConstraintValidator
                 Url::CHECK_DNS_TYPE_SRV,
                 Url::CHECK_DNS_TYPE_TXT,
             ), true)) {
-                throw new InvalidOptionsException(sprintf('Invalid value for option "checkDNS" in constraint %s', get_class($constraint)), array('checkDNS'));
+                throw new InvalidOptionsException(sprintf('Invalid value for option "checkDNS" in constraint %s', \get_class($constraint)), array('checkDNS'));
             }
 
             $host = parse_url($value, PHP_URL_HOST);
 
-            if (!is_string($host) || !checkdnsrr($host, $constraint->checkDNS)) {
+            if (!\is_string($host) || !checkdnsrr($host, $constraint->checkDNS)) {
                 $this->context->buildViolation($constraint->dnsMessage)
                     ->setParameter('{{ value }}', $this->formatValue($host))
                     ->setCode(Url::INVALID_URL_ERROR)
diff --git a/src/Symfony/Component/Validator/Constraints/UuidValidator.php b/src/Symfony/Component/Validator/Constraints/UuidValidator.php
index be177e2255..38e9a0da85 100644
--- a/src/Symfony/Component/Validator/Constraints/UuidValidator.php
+++ b/src/Symfony/Component/Validator/Constraints/UuidValidator.php
@@ -74,7 +74,7 @@ class UuidValidator extends ConstraintValidator
             throw new UnexpectedTypeException($constraint, __NAMESPACE__.'\Uuid');
         }
 
-        if (!is_scalar($value) && !(is_object($value) && method_exists($value, '__toString'))) {
+        if (!is_scalar($value) && !(\is_object($value) && method_exists($value, '__toString'))) {
             throw new UnexpectedTypeException($value, 'string');
         }
 
@@ -235,7 +235,7 @@ class UuidValidator extends ConstraintValidator
         }
 
         // Check version
-        if (!in_array($value[self::STRICT_VERSION_POSITION], $constraint->versions)) {
+        if (!\in_array($value[self::STRICT_VERSION_POSITION], $constraint->versions)) {
             $this->context->buildViolation($constraint->message)
                 ->setParameter('{{ value }}', $this->formatValue($value))
                 ->setCode(Uuid::INVALID_VERSION_ERROR)
diff --git a/src/Symfony/Component/Validator/ContainerConstraintValidatorFactory.php b/src/Symfony/Component/Validator/ContainerConstraintValidatorFactory.php
index a40be361f1..43c8a0d7cb 100644
--- a/src/Symfony/Component/Validator/ContainerConstraintValidatorFactory.php
+++ b/src/Symfony/Component/Validator/ContainerConstraintValidatorFactory.php
@@ -46,7 +46,7 @@ class ContainerConstraintValidatorFactory implements ConstraintValidatorFactoryI
                 $this->validators[$name] = $this->container->get($name);
             } else {
                 if (!class_exists($name)) {
-                    throw new ValidatorException(sprintf('Constraint validator "%s" does not exist or it is not enabled. Check the "validatedBy" method in your constraint class "%s".', $name, get_class($constraint)));
+                    throw new ValidatorException(sprintf('Constraint validator "%s" does not exist or it is not enabled. Check the "validatedBy" method in your constraint class "%s".', $name, \get_class($constraint)));
                 }
 
                 $this->validators[$name] = new $name();
diff --git a/src/Symfony/Component/Validator/DataCollector/ValidatorDataCollector.php b/src/Symfony/Component/Validator/DataCollector/ValidatorDataCollector.php
index 1b91600a49..f7165e5fbd 100644
--- a/src/Symfony/Component/Validator/DataCollector/ValidatorDataCollector.php
+++ b/src/Symfony/Component/Validator/DataCollector/ValidatorDataCollector.php
@@ -59,7 +59,7 @@ class ValidatorDataCollector extends DataCollector implements LateDataCollectorI
         $collected = $this->validator->getCollectedData();
         $this->data['calls'] = $this->cloneVar($collected);
         $this->data['violations_count'] = array_reduce($collected, function ($previous, $item) {
-            return $previous + count($item['violations']);
+            return $previous + \count($item['violations']);
         }, 0);
     }
 
@@ -103,7 +103,7 @@ class ValidatorDataCollector extends DataCollector implements LateDataCollectorI
             FormInterface::class => function (FormInterface $f, array $a) {
                 return array(
                     Caster::PREFIX_VIRTUAL.'name' => $f->getName(),
-                    Caster::PREFIX_VIRTUAL.'type_class' => new ClassStub(get_class($f->getConfig()->getType()->getInnerType())),
+                    Caster::PREFIX_VIRTUAL.'type_class' => new ClassStub(\get_class($f->getConfig()->getType()->getInnerType())),
                     Caster::PREFIX_VIRTUAL.'data' => $f->getData(),
                 );
             },
diff --git a/src/Symfony/Component/Validator/Exception/UnexpectedTypeException.php b/src/Symfony/Component/Validator/Exception/UnexpectedTypeException.php
index 3240aab603..55d56dd9c8 100644
--- a/src/Symfony/Component/Validator/Exception/UnexpectedTypeException.php
+++ b/src/Symfony/Component/Validator/Exception/UnexpectedTypeException.php
@@ -15,6 +15,6 @@ class UnexpectedTypeException extends ValidatorException
 {
     public function __construct($value, string $expectedType)
     {
-        parent::__construct(sprintf('Expected argument of type "%s", "%s" given', $expectedType, is_object($value) ? get_class($value) : gettype($value)));
+        parent::__construct(sprintf('Expected argument of type "%s", "%s" given', $expectedType, \is_object($value) ? \get_class($value) : \gettype($value)));
     }
 }
diff --git a/src/Symfony/Component/Validator/Mapping/ClassMetadata.php b/src/Symfony/Component/Validator/Mapping/ClassMetadata.php
index d777386144..cffbaf6366 100644
--- a/src/Symfony/Component/Validator/Mapping/ClassMetadata.php
+++ b/src/Symfony/Component/Validator/Mapping/ClassMetadata.php
@@ -174,17 +174,17 @@ class ClassMetadata extends GenericMetadata implements ClassMetadataInterface
      */
     public function addConstraint(Constraint $constraint)
     {
-        if (!in_array(Constraint::CLASS_CONSTRAINT, (array) $constraint->getTargets())) {
+        if (!\in_array(Constraint::CLASS_CONSTRAINT, (array) $constraint->getTargets())) {
             throw new ConstraintDefinitionException(sprintf(
                 'The constraint "%s" cannot be put on classes.',
-                get_class($constraint)
+                \get_class($constraint)
             ));
         }
 
         if ($constraint instanceof Valid) {
             throw new ConstraintDefinitionException(sprintf(
                 'The constraint "%s" cannot be put on classes.',
-                get_class($constraint)
+                \get_class($constraint)
             ));
         }
 
@@ -345,7 +345,7 @@ class ClassMetadata extends GenericMetadata implements ClassMetadataInterface
                 $member = clone $member;
 
                 foreach ($member->getConstraints() as $constraint) {
-                    if (in_array($constraint::DEFAULT_GROUP, $constraint->groups, true)) {
+                    if (\in_array($constraint::DEFAULT_GROUP, $constraint->groups, true)) {
                         $member->constraintsByGroup[$this->getDefaultGroup()][] = $constraint;
                     }
 
@@ -410,15 +410,15 @@ class ClassMetadata extends GenericMetadata implements ClassMetadataInterface
             throw new GroupDefinitionException('Defining a static group sequence is not allowed with a group sequence provider');
         }
 
-        if (is_array($groupSequence)) {
+        if (\is_array($groupSequence)) {
             $groupSequence = new GroupSequence($groupSequence);
         }
 
-        if (in_array(Constraint::DEFAULT_GROUP, $groupSequence->groups, true)) {
+        if (\in_array(Constraint::DEFAULT_GROUP, $groupSequence->groups, true)) {
             throw new GroupDefinitionException(sprintf('The group "%s" is not allowed in group sequences', Constraint::DEFAULT_GROUP));
         }
 
-        if (!in_array($this->getDefaultGroup(), $groupSequence->groups, true)) {
+        if (!\in_array($this->getDefaultGroup(), $groupSequence->groups, true)) {
             throw new GroupDefinitionException(sprintf('The group "%s" is missing in the group sequence', $this->getDefaultGroup()));
         }
 
@@ -432,7 +432,7 @@ class ClassMetadata extends GenericMetadata implements ClassMetadataInterface
      */
     public function hasGroupSequence()
     {
-        return $this->groupSequence && count($this->groupSequence->groups) > 0;
+        return $this->groupSequence && \count($this->groupSequence->groups) > 0;
     }
 
     /**
diff --git a/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php b/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php
index 85ffcb7f54..33a0324940 100644
--- a/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php
+++ b/src/Symfony/Component/Validator/Mapping/Factory/LazyLoadingMetadataFactory.php
@@ -78,11 +78,11 @@ class LazyLoadingMetadataFactory implements MetadataFactoryInterface
      */
     public function getMetadataFor($value)
     {
-        if (!is_object($value) && !is_string($value)) {
-            throw new NoSuchMetadataException(sprintf('Cannot create metadata for non-objects. Got: %s', gettype($value)));
+        if (!\is_object($value) && !\is_string($value)) {
+            throw new NoSuchMetadataException(sprintf('Cannot create metadata for non-objects. Got: %s', \gettype($value)));
         }
 
-        $class = ltrim(is_object($value) ? get_class($value) : $value, '\\');
+        $class = ltrim(\is_object($value) ? \get_class($value) : $value, '\\');
 
         if (isset($this->loadedClasses[$class])) {
             return $this->loadedClasses[$class];
@@ -154,11 +154,11 @@ class LazyLoadingMetadataFactory implements MetadataFactoryInterface
      */
     public function hasMetadataFor($value)
     {
-        if (!is_object($value) && !is_string($value)) {
+        if (!\is_object($value) && !\is_string($value)) {
             return false;
         }
 
-        $class = ltrim(is_object($value) ? get_class($value) : $value, '\\');
+        $class = ltrim(\is_object($value) ? \get_class($value) : $value, '\\');
 
         return class_exists($class) || interface_exists($class, false);
     }
diff --git a/src/Symfony/Component/Validator/Mapping/GenericMetadata.php b/src/Symfony/Component/Validator/Mapping/GenericMetadata.php
index 83099aa5e3..21f9da1334 100644
--- a/src/Symfony/Component/Validator/Mapping/GenericMetadata.php
+++ b/src/Symfony/Component/Validator/Mapping/GenericMetadata.php
@@ -125,7 +125,7 @@ class GenericMetadata implements MetadataInterface
             throw new ConstraintDefinitionException(sprintf(
                 'The constraint "%s" can only be put on classes. Please use '.
                 '"Symfony\Component\Validator\Constraints\Valid" instead.',
-                get_class($constraint)
+                \get_class($constraint)
             ));
         }
 
@@ -181,7 +181,7 @@ class GenericMetadata implements MetadataInterface
      */
     public function hasConstraints()
     {
-        return count($this->constraints) > 0;
+        return \count($this->constraints) > 0;
     }
 
     /**
diff --git a/src/Symfony/Component/Validator/Mapping/Loader/LoaderChain.php b/src/Symfony/Component/Validator/Mapping/Loader/LoaderChain.php
index f82c400002..de80dcd8ad 100644
--- a/src/Symfony/Component/Validator/Mapping/Loader/LoaderChain.php
+++ b/src/Symfony/Component/Validator/Mapping/Loader/LoaderChain.php
@@ -36,7 +36,7 @@ class LoaderChain implements LoaderInterface
     {
         foreach ($loaders as $loader) {
             if (!$loader instanceof LoaderInterface) {
-                throw new MappingException(sprintf('Class %s is expected to implement LoaderInterface', get_class($loader)));
+                throw new MappingException(sprintf('Class %s is expected to implement LoaderInterface', \get_class($loader)));
             }
         }
 
diff --git a/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php b/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php
index 6548c5aece..398d81e936 100644
--- a/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php
@@ -75,17 +75,17 @@ class XmlFileLoader extends FileLoader
         $constraints = array();
 
         foreach ($nodes as $node) {
-            if (count($node) > 0) {
-                if (count($node->value) > 0) {
+            if (\count($node) > 0) {
+                if (\count($node->value) > 0) {
                     $options = $this->parseValues($node->value);
-                } elseif (count($node->constraint) > 0) {
+                } elseif (\count($node->constraint) > 0) {
                     $options = $this->parseConstraints($node->constraint);
-                } elseif (count($node->option) > 0) {
+                } elseif (\count($node->option) > 0) {
                     $options = $this->parseOptions($node->option);
                 } else {
                     $options = array();
                 }
-            } elseif (strlen((string) $node) > 0) {
+            } elseif (\strlen((string) $node) > 0) {
                 $options = XmlUtils::phpize(trim($node));
             } else {
                 $options = null;
@@ -109,10 +109,10 @@ class XmlFileLoader extends FileLoader
         $values = array();
 
         foreach ($nodes as $node) {
-            if (count($node) > 0) {
-                if (count($node->value) > 0) {
+            if (\count($node) > 0) {
+                if (\count($node->value) > 0) {
                     $value = $this->parseValues($node->value);
-                } elseif (count($node->constraint) > 0) {
+                } elseif (\count($node->constraint) > 0) {
                     $value = $this->parseConstraints($node->constraint);
                 } else {
                     $value = array();
@@ -143,17 +143,17 @@ class XmlFileLoader extends FileLoader
         $options = array();
 
         foreach ($nodes as $node) {
-            if (count($node) > 0) {
-                if (count($node->value) > 0) {
+            if (\count($node) > 0) {
+                if (\count($node->value) > 0) {
                     $value = $this->parseValues($node->value);
-                } elseif (count($node->constraint) > 0) {
+                } elseif (\count($node->constraint) > 0) {
                     $value = $this->parseConstraints($node->constraint);
                 } else {
                     $value = array();
                 }
             } else {
                 $value = XmlUtils::phpize($node);
-                if (is_string($value)) {
+                if (\is_string($value)) {
                     $value = trim($value);
                 }
             }
@@ -203,12 +203,12 @@ class XmlFileLoader extends FileLoader
 
     private function loadClassMetadataFromXml(ClassMetadata $metadata, \SimpleXMLElement $classDescription)
     {
-        if (count($classDescription->{'group-sequence-provider'}) > 0) {
+        if (\count($classDescription->{'group-sequence-provider'}) > 0) {
             $metadata->setGroupSequenceProvider(true);
         }
 
         foreach ($classDescription->{'group-sequence'} as $groupSequence) {
-            if (count($groupSequence->value) > 0) {
+            if (\count($groupSequence->value) > 0) {
                 $metadata->setGroupSequence($this->parseValues($groupSequence[0]->value));
             }
         }
diff --git a/src/Symfony/Component/Validator/Mapping/Loader/YamlFileLoader.php b/src/Symfony/Component/Validator/Mapping/Loader/YamlFileLoader.php
index e5e84c38c3..54e969c022 100644
--- a/src/Symfony/Component/Validator/Mapping/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/Validator/Mapping/Loader/YamlFileLoader.php
@@ -83,16 +83,16 @@ class YamlFileLoader extends FileLoader
         $values = array();
 
         foreach ($nodes as $name => $childNodes) {
-            if (is_numeric($name) && is_array($childNodes) && 1 === count($childNodes)) {
+            if (is_numeric($name) && \is_array($childNodes) && 1 === \count($childNodes)) {
                 $options = current($childNodes);
 
-                if (is_array($options)) {
+                if (\is_array($options)) {
                     $options = $this->parseNodes($options);
                 }
 
                 $values[] = $this->newConstraint(key($childNodes), $options);
             } else {
-                if (is_array($childNodes)) {
+                if (\is_array($childNodes)) {
                     $childNodes = $this->parseNodes($childNodes);
                 }
 
@@ -127,7 +127,7 @@ class YamlFileLoader extends FileLoader
         }
 
         // not an array
-        if (!is_array($classes)) {
+        if (!\is_array($classes)) {
             throw new \InvalidArgumentException(sprintf('The file "%s" must contain a YAML array.', $this->file));
         }
 
@@ -163,13 +163,13 @@ class YamlFileLoader extends FileLoader
             $metadata->setGroupSequence($classDescription['group_sequence']);
         }
 
-        if (isset($classDescription['constraints']) && is_array($classDescription['constraints'])) {
+        if (isset($classDescription['constraints']) && \is_array($classDescription['constraints'])) {
             foreach ($this->parseNodes($classDescription['constraints']) as $constraint) {
                 $metadata->addConstraint($constraint);
             }
         }
 
-        if (isset($classDescription['properties']) && is_array($classDescription['properties'])) {
+        if (isset($classDescription['properties']) && \is_array($classDescription['properties'])) {
             foreach ($classDescription['properties'] as $property => $constraints) {
                 if (null !== $constraints) {
                     foreach ($this->parseNodes($constraints) as $constraint) {
@@ -179,7 +179,7 @@ class YamlFileLoader extends FileLoader
             }
         }
 
-        if (isset($classDescription['getters']) && is_array($classDescription['getters'])) {
+        if (isset($classDescription['getters']) && \is_array($classDescription['getters'])) {
             foreach ($classDescription['getters'] as $getter => $constraints) {
                 if (null !== $constraints) {
                     foreach ($this->parseNodes($constraints) as $constraint) {
diff --git a/src/Symfony/Component/Validator/Mapping/MemberMetadata.php b/src/Symfony/Component/Validator/Mapping/MemberMetadata.php
index 6d303e1ee8..d4621cb7dd 100644
--- a/src/Symfony/Component/Validator/Mapping/MemberMetadata.php
+++ b/src/Symfony/Component/Validator/Mapping/MemberMetadata.php
@@ -71,10 +71,10 @@ abstract class MemberMetadata extends GenericMetadata implements PropertyMetadat
      */
     public function addConstraint(Constraint $constraint)
     {
-        if (!in_array(Constraint::PROPERTY_CONSTRAINT, (array) $constraint->getTargets())) {
+        if (!\in_array(Constraint::PROPERTY_CONSTRAINT, (array) $constraint->getTargets())) {
             throw new ConstraintDefinitionException(sprintf(
                 'The constraint %s cannot be put on properties or getters',
-                get_class($constraint)
+                \get_class($constraint)
             ));
         }
 
@@ -166,7 +166,7 @@ abstract class MemberMetadata extends GenericMetadata implements PropertyMetadat
      */
     public function getReflectionMember($objectOrClassName)
     {
-        $className = is_string($objectOrClassName) ? $objectOrClassName : get_class($objectOrClassName);
+        $className = \is_string($objectOrClassName) ? $objectOrClassName : \get_class($objectOrClassName);
         if (!isset($this->reflMember[$className])) {
             $this->reflMember[$className] = $this->newReflectionMember($objectOrClassName);
         }
diff --git a/src/Symfony/Component/Validator/Mapping/PropertyMetadata.php b/src/Symfony/Component/Validator/Mapping/PropertyMetadata.php
index f15ca30884..74ecf02cf3 100644
--- a/src/Symfony/Component/Validator/Mapping/PropertyMetadata.php
+++ b/src/Symfony/Component/Validator/Mapping/PropertyMetadata.php
@@ -56,7 +56,7 @@ class PropertyMetadata extends MemberMetadata
      */
     protected function newReflectionMember($objectOrClassName)
     {
-        $originalClass = is_string($objectOrClassName) ? $objectOrClassName : get_class($objectOrClassName);
+        $originalClass = \is_string($objectOrClassName) ? $objectOrClassName : \get_class($objectOrClassName);
 
         while (!property_exists($objectOrClassName, $this->getName())) {
             $objectOrClassName = get_parent_class($objectOrClassName);
diff --git a/src/Symfony/Component/Validator/Test/ConstraintValidatorTestCase.php b/src/Symfony/Component/Validator/Test/ConstraintValidatorTestCase.php
index 8e3b2a9f79..087a90a185 100644
--- a/src/Symfony/Component/Validator/Test/ConstraintValidatorTestCase.php
+++ b/src/Symfony/Component/Validator/Test/ConstraintValidatorTestCase.php
@@ -121,8 +121,8 @@ abstract class ConstraintValidatorTestCase extends TestCase
     protected function setObject($object)
     {
         $this->object = $object;
-        $this->metadata = is_object($object)
-            ? new ClassMetadata(get_class($object))
+        $this->metadata = \is_object($object)
+            ? new ClassMetadata(\get_class($object))
             : null;
 
         $this->context->setNode($this->value, $this->object, $this->metadata, $this->propertyPath);
@@ -131,8 +131,8 @@ abstract class ConstraintValidatorTestCase extends TestCase
     protected function setProperty($object, $property)
     {
         $this->object = $object;
-        $this->metadata = is_object($object)
-            ? new PropertyMetadata(get_class($object), $property)
+        $this->metadata = \is_object($object)
+            ? new PropertyMetadata(\get_class($object), $property)
             : null;
 
         $this->context->setNode($this->value, $this->object, $this->metadata, $this->propertyPath);
@@ -192,7 +192,7 @@ abstract class ConstraintValidatorTestCase extends TestCase
 
     protected function assertNoViolation()
     {
-        $this->assertSame(0, $violationsCount = count($this->context->getViolations()), sprintf('0 violation expected. Got %u.', $violationsCount));
+        $this->assertSame(0, $violationsCount = \count($this->context->getViolations()), sprintf('0 violation expected. Got %u.', $violationsCount));
     }
 
     /**
@@ -314,7 +314,7 @@ class ConstraintViolationAssertion
 
         $violations = iterator_to_array($this->context->getViolations());
 
-        Assert::assertSame($expectedCount = count($expected), $violationsCount = count($violations), sprintf('%u violation(s) expected. Got %u.', $expectedCount, $violationsCount));
+        Assert::assertSame($expectedCount = \count($expected), $violationsCount = \count($violations), sprintf('%u violation(s) expected. Got %u.', $expectedCount, $violationsCount));
 
         reset($violations);
 
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/AbstractComparisonValidatorTestCase.php b/src/Symfony/Component/Validator/Tests/Constraints/AbstractComparisonValidatorTestCase.php
index 93898bc6ec..5e9f2bceaf 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/AbstractComparisonValidatorTestCase.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/AbstractComparisonValidatorTestCase.php
@@ -179,9 +179,9 @@ abstract class AbstractComparisonValidatorTestCase extends ConstraintValidatorTe
 
         if (method_exists($this, 'expectException')) {
             $this->expectException(ConstraintDefinitionException::class);
-            $this->expectExceptionMessage(sprintf('Invalid property path "foo" provided to "%s" constraint', get_class($constraint)));
+            $this->expectExceptionMessage(sprintf('Invalid property path "foo" provided to "%s" constraint', \get_class($constraint)));
         } else {
-            $this->setExpectedException(ConstraintDefinitionException::class, sprintf('Invalid property path "foo" provided to "%s" constraint', get_class($constraint)));
+            $this->setExpectedException(ConstraintDefinitionException::class, sprintf('Invalid property path "foo" provided to "%s" constraint', \get_class($constraint)));
         }
 
         $object = new ComparisonTest_Class(5);
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/CardSchemeValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/CardSchemeValidatorTest.php
index 40c0ce43cf..b0280713d5 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/CardSchemeValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/CardSchemeValidatorTest.php
@@ -59,7 +59,7 @@ class CardSchemeValidatorTest extends ConstraintValidatorTestCase
         $this->validator->validate($number, $constraint);
 
         $this->buildViolation('myMessage')
-            ->setParameter('{{ value }}', is_string($number) ? '"'.$number.'"' : $number)
+            ->setParameter('{{ value }}', \is_string($number) ? '"'.$number.'"' : $number)
             ->setCode($code)
             ->assertRaised();
     }
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/CountValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/CountValidatorTest.php
index c9d68ee313..d23188a098 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/CountValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/CountValidatorTest.php
@@ -115,7 +115,7 @@ abstract class CountValidatorTest extends ConstraintValidatorTestCase
         $this->validator->validate($value, $constraint);
 
         $this->buildViolation('myMessage')
-            ->setParameter('{{ count }}', count($value))
+            ->setParameter('{{ count }}', \count($value))
             ->setParameter('{{ limit }}', 4)
             ->setInvalidValue($value)
             ->setPlural(4)
@@ -136,7 +136,7 @@ abstract class CountValidatorTest extends ConstraintValidatorTestCase
         $this->validator->validate($value, $constraint);
 
         $this->buildViolation('myMessage')
-            ->setParameter('{{ count }}', count($value))
+            ->setParameter('{{ count }}', \count($value))
             ->setParameter('{{ limit }}', 4)
             ->setInvalidValue($value)
             ->setPlural(4)
@@ -158,7 +158,7 @@ abstract class CountValidatorTest extends ConstraintValidatorTestCase
         $this->validator->validate($value, $constraint);
 
         $this->buildViolation('myMessage')
-            ->setParameter('{{ count }}', count($value))
+            ->setParameter('{{ count }}', \count($value))
             ->setParameter('{{ limit }}', 4)
             ->setInvalidValue($value)
             ->setPlural(4)
@@ -180,7 +180,7 @@ abstract class CountValidatorTest extends ConstraintValidatorTestCase
         $this->validator->validate($value, $constraint);
 
         $this->buildViolation('myMessage')
-            ->setParameter('{{ count }}', count($value))
+            ->setParameter('{{ count }}', \count($value))
             ->setParameter('{{ limit }}', 4)
             ->setInvalidValue($value)
             ->setPlural(4)
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/EmailValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/EmailValidatorTest.php
index 163f00f742..e8e9cfc0db 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/EmailValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/EmailValidatorTest.php
@@ -288,10 +288,10 @@ class EmailValidatorTest extends ConstraintValidatorTestCase
             array('"test""test"@iana.org'),
             array('"test"."test"@iana.org'),
             array('"test".test@iana.org'),
-            array('"test"'.chr(0).'@iana.org'),
+            array('"test"'.\chr(0).'@iana.org'),
             array('"test\"@iana.org'),
-            array(chr(226).'@iana.org'),
-            array('test@'.chr(226).'.org'),
+            array(\chr(226).'@iana.org'),
+            array('test@'.\chr(226).'.org'),
             array('\r\ntest@iana.org'),
             array('\r\n test@iana.org'),
             array('\r\n \r\ntest@iana.org'),
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php
index 05c2d499a3..f9fa2ef16f 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/FileValidatorTest.php
@@ -40,7 +40,7 @@ abstract class FileValidatorTest extends ConstraintValidatorTestCase
     {
         parent::tearDown();
 
-        if (is_resource($this->file)) {
+        if (\is_resource($this->file)) {
             fclose($this->file);
         }
 
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/ImageValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/ImageValidatorTest.php
index 05ab7e2f88..9d80f88d89 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/ImageValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/ImageValidatorTest.php
@@ -389,7 +389,7 @@ class ImageValidatorTest extends ConstraintValidatorTestCase
 
     public function testCorrupted()
     {
-        if (!function_exists('imagecreatefromstring')) {
+        if (!\function_exists('imagecreatefromstring')) {
             $this->markTestSkipped('This test require GD extension');
         }
 
diff --git a/src/Symfony/Component/Validator/Tests/Constraints/IsbnValidatorTest.php b/src/Symfony/Component/Validator/Tests/Constraints/IsbnValidatorTest.php
index 344edb99f3..f810fc9820 100644
--- a/src/Symfony/Component/Validator/Tests/Constraints/IsbnValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Constraints/IsbnValidatorTest.php
@@ -60,7 +60,7 @@ class IsbnValidatorTest extends ConstraintValidatorTestCase
             array('1A34567890', Isbn::INVALID_CHARACTERS_ERROR),
             // chr(1) evaluates to 0
             // 2070546810 is valid
-            array('2'.chr(1).'70546810', Isbn::INVALID_CHARACTERS_ERROR),
+            array('2'.\chr(1).'70546810', Isbn::INVALID_CHARACTERS_ERROR),
         );
     }
 
@@ -98,7 +98,7 @@ class IsbnValidatorTest extends ConstraintValidatorTestCase
             array('978-272C442282', Isbn::INVALID_CHARACTERS_ERROR),
             // chr(1) evaluates to 0
             // 978-2070546817 is valid
-            array('978-2'.chr(1).'70546817', Isbn::INVALID_CHARACTERS_ERROR),
+            array('978-2'.\chr(1).'70546817', Isbn::INVALID_CHARACTERS_ERROR),
         );
     }
 
diff --git a/src/Symfony/Component/Validator/Tests/DependencyInjection/AddConstraintValidatorsPassTest.php b/src/Symfony/Component/Validator/Tests/DependencyInjection/AddConstraintValidatorsPassTest.php
index 05167e84ca..5f39acb430 100644
--- a/src/Symfony/Component/Validator/Tests/DependencyInjection/AddConstraintValidatorsPassTest.php
+++ b/src/Symfony/Component/Validator/Tests/DependencyInjection/AddConstraintValidatorsPassTest.php
@@ -65,8 +65,8 @@ class AddConstraintValidatorsPassTest extends TestCase
     {
         $container = new ContainerBuilder();
 
-        $definitionsBefore = count($container->getDefinitions());
-        $aliasesBefore = count($container->getAliases());
+        $definitionsBefore = \count($container->getDefinitions());
+        $aliasesBefore = \count($container->getAliases());
 
         $addConstraintValidatorsPass = new AddConstraintValidatorsPass();
         $addConstraintValidatorsPass->process($container);
diff --git a/src/Symfony/Component/Validator/Tests/Fixtures/Countable.php b/src/Symfony/Component/Validator/Tests/Fixtures/Countable.php
index 282d78d45a..afc42376a2 100644
--- a/src/Symfony/Component/Validator/Tests/Fixtures/Countable.php
+++ b/src/Symfony/Component/Validator/Tests/Fixtures/Countable.php
@@ -22,6 +22,6 @@ class Countable implements \Countable
 
     public function count()
     {
-        return count($this->content);
+        return \count($this->content);
     }
 }
diff --git a/src/Symfony/Component/Validator/Tests/Fixtures/CustomArrayObject.php b/src/Symfony/Component/Validator/Tests/Fixtures/CustomArrayObject.php
index 41eac961ac..feb25318eb 100644
--- a/src/Symfony/Component/Validator/Tests/Fixtures/CustomArrayObject.php
+++ b/src/Symfony/Component/Validator/Tests/Fixtures/CustomArrayObject.php
@@ -55,7 +55,7 @@ class CustomArrayObject implements \ArrayAccess, \IteratorAggregate, \Countable,
 
     public function count()
     {
-        return count($this->array);
+        return \count($this->array);
     }
 
     public function serialize()
diff --git a/src/Symfony/Component/Validator/Tests/Fixtures/FakeMetadataFactory.php b/src/Symfony/Component/Validator/Tests/Fixtures/FakeMetadataFactory.php
index 98aa57ce80..1b5a704d46 100644
--- a/src/Symfony/Component/Validator/Tests/Fixtures/FakeMetadataFactory.php
+++ b/src/Symfony/Component/Validator/Tests/Fixtures/FakeMetadataFactory.php
@@ -23,13 +23,13 @@ class FakeMetadataFactory implements MetadataFactoryInterface
     {
         $hash = null;
 
-        if (is_object($class)) {
+        if (\is_object($class)) {
             $hash = spl_object_hash($class);
-            $class = get_class($class);
+            $class = \get_class($class);
         }
 
-        if (!is_string($class)) {
-            throw new NoSuchMetadataException(sprintf('No metadata for type %s', gettype($class)));
+        if (!\is_string($class)) {
+            throw new NoSuchMetadataException(sprintf('No metadata for type %s', \gettype($class)));
         }
 
         if (!isset($this->metadatas[$class])) {
@@ -47,12 +47,12 @@ class FakeMetadataFactory implements MetadataFactoryInterface
     {
         $hash = null;
 
-        if (is_object($class)) {
+        if (\is_object($class)) {
             $hash = spl_object_hash($class);
-            $class = get_class($class);
+            $class = \get_class($class);
         }
 
-        if (!is_string($class)) {
+        if (!\is_string($class)) {
             return false;
         }
 
@@ -66,7 +66,7 @@ class FakeMetadataFactory implements MetadataFactoryInterface
 
     public function addMetadataForValue($value, MetadataInterface $metadata)
     {
-        $key = is_object($value) ? spl_object_hash($value) : $value;
+        $key = \is_object($value) ? spl_object_hash($value) : $value;
         $this->metadatas[$key] = $metadata;
     }
 }
diff --git a/src/Symfony/Component/Validator/Tests/Resources/TranslationFilesTest.php b/src/Symfony/Component/Validator/Tests/Resources/TranslationFilesTest.php
index d2b8a99011..64b3f78934 100644
--- a/src/Symfony/Component/Validator/Tests/Resources/TranslationFilesTest.php
+++ b/src/Symfony/Component/Validator/Tests/Resources/TranslationFilesTest.php
@@ -33,15 +33,15 @@ class TranslationFilesTest extends TestCase
     {
         return array_map(
             function ($filePath) { return (array) $filePath; },
-            glob(dirname(dirname(__DIR__)).'/Resources/translations/*.xlf')
+            glob(\dirname(\dirname(__DIR__)).'/Resources/translations/*.xlf')
         );
     }
 
     public function testNorwegianAlias()
     {
         $this->assertFileEquals(
-            dirname(dirname(__DIR__)).'/Resources/translations/validators.nb.xlf',
-            dirname(dirname(__DIR__)).'/Resources/translations/validators.no.xlf',
+            \dirname(\dirname(__DIR__)).'/Resources/translations/validators.nb.xlf',
+            \dirname(\dirname(__DIR__)).'/Resources/translations/validators.no.xlf',
             'The NO locale should be an alias for the NB variant of the Norwegian language.'
         );
     }
diff --git a/src/Symfony/Component/Validator/Tests/Validator/AbstractValidatorTest.php b/src/Symfony/Component/Validator/Tests/Validator/AbstractValidatorTest.php
index 360d84f985..7d303ce8a5 100644
--- a/src/Symfony/Component/Validator/Tests/Validator/AbstractValidatorTest.php
+++ b/src/Symfony/Component/Validator/Tests/Validator/AbstractValidatorTest.php
@@ -1172,7 +1172,7 @@ abstract class AbstractValidatorTest extends TestCase
             $context->addViolation('Violation in Group 3');
         };
 
-        $metadata = new ClassMetadata(get_class($entity));
+        $metadata = new ClassMetadata(\get_class($entity));
         $metadata->addConstraint(new Callback(array(
             'callback' => function () {},
             'groups' => 'Group 1',
@@ -1192,7 +1192,7 @@ abstract class AbstractValidatorTest extends TestCase
         $violations = $this->validate($entity, null, 'Default');
 
         /* @var ConstraintViolationInterface[] $violations */
-        $this->assertCount(count($assertViolations), $violations);
+        $this->assertCount(\count($assertViolations), $violations);
         foreach ($assertViolations as $key => $message) {
             $this->assertSame($message, $violations[$key]->getMessage());
         }
diff --git a/src/Symfony/Component/Validator/Validator/RecursiveContextualValidator.php b/src/Symfony/Component/Validator/Validator/RecursiveContextualValidator.php
index d1166ad913..1469bee397 100644
--- a/src/Symfony/Component/Validator/Validator/RecursiveContextualValidator.php
+++ b/src/Symfony/Component/Validator/Validator/RecursiveContextualValidator.php
@@ -99,7 +99,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
         if (null !== $constraints) {
             // You can pass a single constraint or an array of constraints
             // Make sure to deal with an array in the rest of the code
-            if (!is_array($constraints)) {
+            if (!\is_array($constraints)) {
                 $constraints = array($constraints);
             }
 
@@ -109,7 +109,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             $this->validateGenericNode(
                 $value,
                 $previousObject,
-                is_object($value) ? spl_object_hash($value) : null,
+                \is_object($value) ? spl_object_hash($value) : null,
                 $metadata,
                 $this->defaultPropertyPath,
                 $groups,
@@ -130,7 +130,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
 
         // If an object is passed without explicit constraints, validate that
         // object against the constraints defined for the object's class
-        if (is_object($value)) {
+        if (\is_object($value)) {
             $this->validateObject(
                 $value,
                 $this->defaultPropertyPath,
@@ -147,7 +147,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
 
         // If an array is passed without explicit constraints, validate each
         // object in the array
-        if (is_array($value)) {
+        if (\is_array($value)) {
             $this->validateEachObjectIn(
                 $value,
                 $this->defaultPropertyPath,
@@ -164,7 +164,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
         throw new RuntimeException(sprintf(
             'Cannot validate values of type "%s" automatically. Please '.
             'provide a constraint.',
-            gettype($value)
+            \gettype($value)
         ));
     }
 
@@ -180,7 +180,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
                 'The metadata factory should return instances of '.
                 '"\Symfony\Component\Validator\Mapping\ClassMetadataInterface", '.
                 'got: "%s".',
-                is_object($classMetadata) ? get_class($classMetadata) : gettype($classMetadata)
+                \is_object($classMetadata) ? \get_class($classMetadata) : \gettype($classMetadata)
             ));
         }
 
@@ -201,7 +201,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             $this->validateGenericNode(
                 $propertyValue,
                 $object,
-                $cacheKey.':'.get_class($object).':'.$propertyName,
+                $cacheKey.':'.\get_class($object).':'.$propertyName,
                 $propertyMetadata,
                 $propertyPath,
                 $groups,
@@ -229,16 +229,16 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
                 'The metadata factory should return instances of '.
                 '"\Symfony\Component\Validator\Mapping\ClassMetadataInterface", '.
                 'got: "%s".',
-                is_object($classMetadata) ? get_class($classMetadata) : gettype($classMetadata)
+                \is_object($classMetadata) ? \get_class($classMetadata) : \gettype($classMetadata)
             ));
         }
 
         $propertyMetadatas = $classMetadata->getPropertyMetadata($propertyName);
         $groups = $groups ? $this->normalizeGroups($groups) : $this->defaultGroups;
 
-        if (is_object($objectOrClass)) {
+        if (\is_object($objectOrClass)) {
             $object = $objectOrClass;
-            $class = get_class($object);
+            $class = \get_class($object);
             $cacheKey = spl_object_hash($objectOrClass);
             $propertyPath = PropertyPath::append($this->defaultPropertyPath, $propertyName);
         } else {
@@ -292,7 +292,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
      */
     protected function normalizeGroups($groups)
     {
-        if (is_array($groups)) {
+        if (\is_array($groups)) {
             return $groups;
         }
 
@@ -332,7 +332,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
                     'The metadata factory should return instances of '.
                     '"Symfony\Component\Validator\Mapping\ClassMetadataInterface", '.
                     'got: "%s".',
-                    is_object($classMetadata) ? get_class($classMetadata) : gettype($classMetadata)
+                    \is_object($classMetadata) ? \get_class($classMetadata) : \gettype($classMetadata)
                 ));
             }
 
@@ -385,7 +385,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
     private function validateEachObjectIn($collection, $propertyPath, array $groups, ExecutionContextInterface $context)
     {
         foreach ($collection as $key => $value) {
-            if (is_array($value)) {
+            if (\is_array($value)) {
                 // Arrays are always cascaded, independent of the specified
                 // traversal strategy
                 $this->validateEachObjectIn(
@@ -399,7 +399,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             }
 
             // Scalar and null values in the collection are ignored
-            if (is_object($value)) {
+            if (\is_object($value)) {
                 $this->validateObject(
                     $value,
                     $propertyPath.'['.$key.']',
@@ -479,7 +479,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             $defaultOverridden = false;
 
             // Use the object hash for group sequences
-            $groupHash = is_object($group) ? spl_object_hash($group) : $group;
+            $groupHash = \is_object($group) ? spl_object_hash($group) : $group;
 
             if ($context->isGroupValidated($cacheKey, $groupHash)) {
                 // Skip this group when validating the properties and when
@@ -544,7 +544,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
 
         // If no more groups should be validated for the property nodes,
         // we can safely quit
-        if (0 === count($groups)) {
+        if (0 === \count($groups)) {
             return;
         }
 
@@ -559,7 +559,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
                         'The property metadata instances should implement '.
                         '"Symfony\Component\Validator\Mapping\PropertyMetadataInterface", '.
                         'got: "%s".',
-                        is_object($propertyMetadata) ? get_class($propertyMetadata) : gettype($propertyMetadata)
+                        \is_object($propertyMetadata) ? \get_class($propertyMetadata) : \gettype($propertyMetadata)
                     ));
                 }
 
@@ -568,7 +568,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
                 $this->validateGenericNode(
                     $propertyValue,
                     $object,
-                    $cacheKey.':'.get_class($object).':'.$propertyName,
+                    $cacheKey.':'.\get_class($object).':'.$propertyName,
                     $propertyMetadata,
                     PropertyPath::append($propertyPath, $propertyName),
                     $groups,
@@ -600,7 +600,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             throw new ConstraintDefinitionException(sprintf(
                 'Traversal was enabled for "%s", but this class '.
                 'does not implement "\Traversable".',
-                get_class($object)
+                \get_class($object)
             ));
         }
 
@@ -675,7 +675,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             $this->validateInGroup($value, $cacheKey, $metadata, $group, $context);
         }
 
-        if (0 === count($groups)) {
+        if (0 === \count($groups)) {
             return;
         }
 
@@ -686,7 +686,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
         $cascadingStrategy = $metadata->getCascadingStrategy();
 
         // Quit unless we have an array or a cascaded object
-        if (!is_array($value) && !($cascadingStrategy & CascadingStrategy::CASCADE)) {
+        if (!\is_array($value) && !($cascadingStrategy & CascadingStrategy::CASCADE)) {
             return;
         }
 
@@ -699,9 +699,9 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
         // The $cascadedGroups property is set, if the "Default" group is
         // overridden by a group sequence
         // See validateClassNode()
-        $cascadedGroups = null !== $cascadedGroups && count($cascadedGroups) > 0 ? $cascadedGroups : $groups;
+        $cascadedGroups = null !== $cascadedGroups && \count($cascadedGroups) > 0 ? $cascadedGroups : $groups;
 
-        if (is_array($value)) {
+        if (\is_array($value)) {
             // Arrays are always traversed, independent of the specified
             // traversal strategy
             $this->validateEachObjectIn(
@@ -757,7 +757,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
      */
     private function stepThroughGroupSequence($value, $object, $cacheKey, MetadataInterface $metadata = null, $propertyPath, $traversalStrategy, GroupSequence $groupSequence, $cascadedGroup, ExecutionContextInterface $context)
     {
-        $violationCount = count($context->getViolations());
+        $violationCount = \count($context->getViolations());
         $cascadedGroups = $cascadedGroup ? array($cascadedGroup) : null;
 
         foreach ($groupSequence->groups as $groupInSequence) {
@@ -789,7 +789,7 @@ class RecursiveContextualValidator implements ContextualValidatorInterface
             }
 
             // Abort sequence validation if a violation was generated
-            if (count($context->getViolations()) > $violationCount) {
+            if (\count($context->getViolations()) > $violationCount) {
                 break;
             }
         }
diff --git a/src/Symfony/Component/Validator/Validator/RecursiveValidator.php b/src/Symfony/Component/Validator/Validator/RecursiveValidator.php
index 8763f2e668..33c2ec9e47 100644
--- a/src/Symfony/Component/Validator/Validator/RecursiveValidator.php
+++ b/src/Symfony/Component/Validator/Validator/RecursiveValidator.php
@@ -117,7 +117,7 @@ class RecursiveValidator implements ValidatorInterface
     public function validatePropertyValue($objectOrClass, $propertyName, $value, $groups = null)
     {
         // If a class name is passed, take $value as root
-        return $this->startContext(is_object($objectOrClass) ? $objectOrClass : $value)
+        return $this->startContext(\is_object($objectOrClass) ? $objectOrClass : $value)
             ->validatePropertyValue($objectOrClass, $propertyName, $value, $groups)
             ->getViolations();
     }
diff --git a/src/Symfony/Component/Validator/ValidatorBuilder.php b/src/Symfony/Component/Validator/ValidatorBuilder.php
index 4268570858..11c5052f3b 100644
--- a/src/Symfony/Component/Validator/ValidatorBuilder.php
+++ b/src/Symfony/Component/Validator/ValidatorBuilder.php
@@ -213,7 +213,7 @@ class ValidatorBuilder implements ValidatorBuilderInterface
      */
     public function setMetadataFactory(MetadataFactoryInterface $metadataFactory)
     {
-        if (count($this->xmlMappings) > 0 || count($this->yamlMappings) > 0 || count($this->methodMappings) > 0 || null !== $this->annotationReader) {
+        if (\count($this->xmlMappings) > 0 || \count($this->yamlMappings) > 0 || \count($this->methodMappings) > 0 || null !== $this->annotationReader) {
             throw new ValidatorException('You cannot set a custom metadata factory after adding custom mappings. You should do either of both.');
         }
 
@@ -303,9 +303,9 @@ class ValidatorBuilder implements ValidatorBuilderInterface
             $loaders = $this->getLoaders();
             $loader = null;
 
-            if (count($loaders) > 1) {
+            if (\count($loaders) > 1) {
                 $loader = new LoaderChain($loaders);
-            } elseif (1 === count($loaders)) {
+            } elseif (1 === \count($loaders)) {
                 $loader = $loaders[0];
             }
 
diff --git a/src/Symfony/Component/VarDumper/Caster/ArgsStub.php b/src/Symfony/Component/VarDumper/Caster/ArgsStub.php
index 0c53a7bfb7..582d15e261 100644
--- a/src/Symfony/Component/VarDumper/Caster/ArgsStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/ArgsStub.php
@@ -35,10 +35,10 @@ class ArgsStub extends EnumStub
 
             return;
         }
-        if (count($values) < count($params)) {
-            $params = array_slice($params, 0, count($values));
-        } elseif (count($values) > count($params)) {
-            $values[] = new EnumStub(array_splice($values, count($params)), false);
+        if (\count($values) < \count($params)) {
+            $params = \array_slice($params, 0, \count($values));
+        } elseif (\count($values) > \count($params)) {
+            $values[] = new EnumStub(array_splice($values, \count($params)), false);
             $params[] = $variadic;
         }
         if (array('...') === $params) {
diff --git a/src/Symfony/Component/VarDumper/Caster/Caster.php b/src/Symfony/Component/VarDumper/Caster/Caster.php
index 7f4e02283f..c82ce82725 100644
--- a/src/Symfony/Component/VarDumper/Caster/Caster.php
+++ b/src/Symfony/Component/VarDumper/Caster/Caster.php
@@ -117,10 +117,10 @@ class Caster
             } elseif (false === $v || '' === $v || '0' === $v || 0 === $v || 0.0 === $v || array() === $v) {
                 $type |= self::EXCLUDE_EMPTY & $filter;
             }
-            if ((self::EXCLUDE_NOT_IMPORTANT & $filter) && !in_array($k, $listedProperties, true)) {
+            if ((self::EXCLUDE_NOT_IMPORTANT & $filter) && !\in_array($k, $listedProperties, true)) {
                 $type |= self::EXCLUDE_NOT_IMPORTANT;
             }
-            if ((self::EXCLUDE_VERBOSE & $filter) && in_array($k, $listedProperties, true)) {
+            if ((self::EXCLUDE_VERBOSE & $filter) && \in_array($k, $listedProperties, true)) {
                 $type |= self::EXCLUDE_VERBOSE;
             }
 
diff --git a/src/Symfony/Component/VarDumper/Caster/ClassStub.php b/src/Symfony/Component/VarDumper/Caster/ClassStub.php
index 44b5460702..876377bdd4 100644
--- a/src/Symfony/Component/VarDumper/Caster/ClassStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/ClassStub.php
@@ -29,7 +29,7 @@ class ClassStub extends ConstStub
         $this->value = $identifier;
 
         if (0 < $i = strrpos($identifier, '\\')) {
-            $this->attr['ellipsis'] = strlen($identifier) - $i;
+            $this->attr['ellipsis'] = \strlen($identifier) - $i;
             $this->attr['ellipsis-type'] = 'class';
             $this->attr['ellipsis-tail'] = 1;
         }
@@ -38,9 +38,9 @@ class ClassStub extends ConstStub
             if (null !== $callable) {
                 if ($callable instanceof \Closure) {
                     $r = new \ReflectionFunction($callable);
-                } elseif (is_object($callable)) {
+                } elseif (\is_object($callable)) {
                     $r = array($callable, '__invoke');
-                } elseif (is_array($callable)) {
+                } elseif (\is_array($callable)) {
                     $r = $callable;
                 } elseif (false !== $i = strpos($callable, '::')) {
                     $r = array(substr($callable, 0, $i), substr($callable, 2 + $i));
@@ -53,7 +53,7 @@ class ClassStub extends ConstStub
                 $r = new \ReflectionClass($identifier);
             }
 
-            if (is_array($r)) {
+            if (\is_array($r)) {
                 try {
                     $r = new \ReflectionMethod($r[0], $r[1]);
                 } catch (\ReflectionException $e) {
@@ -86,13 +86,13 @@ class ClassStub extends ConstStub
 
     public static function wrapCallable($callable)
     {
-        if (is_object($callable) || !is_callable($callable)) {
+        if (\is_object($callable) || !\is_callable($callable)) {
             return $callable;
         }
 
-        if (!is_array($callable)) {
+        if (!\is_array($callable)) {
             $callable = new static($callable, $callable);
-        } elseif (is_string($callable[0])) {
+        } elseif (\is_string($callable[0])) {
             $callable[0] = new static($callable[0], $callable);
         } else {
             $callable[1] = new static($callable[1], $callable);
diff --git a/src/Symfony/Component/VarDumper/Caster/CutArrayStub.php b/src/Symfony/Component/VarDumper/Caster/CutArrayStub.php
index f2a803053a..0e4fb363d2 100644
--- a/src/Symfony/Component/VarDumper/Caster/CutArrayStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/CutArrayStub.php
@@ -25,6 +25,6 @@ class CutArrayStub extends CutStub
         parent::__construct($value);
 
         $this->preservedSubset = array_intersect_key($value, array_flip($preservedKeys));
-        $this->cut -= count($this->preservedSubset);
+        $this->cut -= \count($this->preservedSubset);
     }
 }
diff --git a/src/Symfony/Component/VarDumper/Caster/CutStub.php b/src/Symfony/Component/VarDumper/Caster/CutStub.php
index 61140eb361..690338f542 100644
--- a/src/Symfony/Component/VarDumper/Caster/CutStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/CutStub.php
@@ -24,17 +24,17 @@ class CutStub extends Stub
     {
         $this->value = $value;
 
-        switch (gettype($value)) {
+        switch (\gettype($value)) {
             case 'object':
                 $this->type = self::TYPE_OBJECT;
-                $this->class = get_class($value);
+                $this->class = \get_class($value);
                 $this->cut = -1;
                 break;
 
             case 'array':
                 $this->type = self::TYPE_ARRAY;
                 $this->class = self::ARRAY_ASSOC;
-                $this->cut = $this->value = count($value);
+                $this->cut = $this->value = \count($value);
                 break;
 
             case 'resource':
@@ -51,7 +51,7 @@ class CutStub extends Stub
             case 'string':
                 $this->type = self::TYPE_STRING;
                 $this->class = preg_match('//u', $value) ? self::STRING_UTF8 : self::STRING_BINARY;
-                $this->cut = self::STRING_BINARY === $this->class ? strlen($value) : mb_strlen($value, 'UTF-8');
+                $this->cut = self::STRING_BINARY === $this->class ? \strlen($value) : mb_strlen($value, 'UTF-8');
                 $this->value = '';
                 break;
         }
diff --git a/src/Symfony/Component/VarDumper/Caster/DateCaster.php b/src/Symfony/Component/VarDumper/Caster/DateCaster.php
index af9ce96055..da6a5a70d6 100644
--- a/src/Symfony/Component/VarDumper/Caster/DateCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/DateCaster.php
@@ -73,7 +73,7 @@ class DateCaster
     {
         $location = $timeZone->getLocation();
         $formatted = (new \DateTime('now', $timeZone))->format($location ? 'e (P)' : 'P');
-        $title = $location && extension_loaded('intl') ? \Locale::getDisplayRegion('-'.$location['country_code']) : '';
+        $title = $location && \extension_loaded('intl') ? \Locale::getDisplayRegion('-'.$location['country_code']) : '';
 
         $z = array(Caster::PREFIX_VIRTUAL.'timezone' => new ConstStub($formatted, $title));
 
@@ -117,6 +117,6 @@ class DateCaster
 
     private static function formatSeconds($s, $us)
     {
-        return sprintf('%02d.%s', $s, 0 === ($len = strlen($t = rtrim($us, '0'))) ? '0' : ($len <= 3 ? str_pad($t, 3, '0') : $us));
+        return sprintf('%02d.%s', $s, 0 === ($len = \strlen($t = rtrim($us, '0'))) ? '0' : ($len <= 3 ? str_pad($t, 3, '0') : $us));
     }
 }
diff --git a/src/Symfony/Component/VarDumper/Caster/ExceptionCaster.php b/src/Symfony/Component/VarDumper/Caster/ExceptionCaster.php
index df61aefb6f..0576d7ad4d 100644
--- a/src/Symfony/Component/VarDumper/Caster/ExceptionCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/ExceptionCaster.php
@@ -71,8 +71,8 @@ class ExceptionCaster
 
         if (isset($a[$xPrefix.'previous'], $a[$trace]) && $a[$xPrefix.'previous'] instanceof \Exception) {
             $b = (array) $a[$xPrefix.'previous'];
-            self::traceUnshift($b[$xPrefix.'trace'], get_class($a[$xPrefix.'previous']), $b[$prefix.'file'], $b[$prefix.'line']);
-            $a[$trace] = new TraceStub($b[$xPrefix.'trace'], false, 0, -count($a[$trace]->value));
+            self::traceUnshift($b[$xPrefix.'trace'], \get_class($a[$xPrefix.'previous']), $b[$prefix.'file'], $b[$prefix.'line']);
+            $a[$trace] = new TraceStub($b[$xPrefix.'trace'], false, 0, -\count($a[$trace]->value));
         }
 
         unset($a[$xPrefix.'previous'], $a[$prefix.'code'], $a[$prefix.'file'], $a[$prefix.'line']);
@@ -118,7 +118,7 @@ class ExceptionCaster
         $prefix = Caster::PREFIX_VIRTUAL;
 
         $a = array();
-        $j = count($frames);
+        $j = \count($frames);
         if (0 > $i = $trace->sliceOffset) {
             $i = max(0, $j + $i);
         }
@@ -175,7 +175,7 @@ class ExceptionCaster
             $lastCall = $call;
         }
         if (null !== $trace->sliceLength) {
-            $a = array_slice($a, 0, $trace->sliceLength, true);
+            $a = \array_slice($a, 0, $trace->sliceLength, true);
         }
 
         return $a;
@@ -199,7 +199,7 @@ class ExceptionCaster
                 $a[$prefix.'src'] = self::$framesCache[$cacheKey];
             } else {
                 if (preg_match('/\((\d+)\)(?:\([\da-f]{32}\))? : (?:eval\(\)\'d code|runtime-created function)$/', $f['file'], $match)) {
-                    $f['file'] = substr($f['file'], 0, -strlen($match[0]));
+                    $f['file'] = substr($f['file'], 0, -\strlen($match[0]));
                     $f['line'] = (int) $match[1];
                 }
                 $caller = isset($f['function']) ? sprintf('in %s() on line %d', (isset($f['class']) ? $f['class'].$f['type'] : '').$f['function'], $f['line']) : null;
@@ -212,7 +212,7 @@ class ExceptionCaster
 
                 if (file_exists($f['file']) && 0 <= self::$srcContext) {
                     if (!empty($f['class']) && (is_subclass_of($f['class'], 'Twig\Template') || is_subclass_of($f['class'], 'Twig_Template')) && method_exists($f['class'], 'getDebugInfo')) {
-                        $template = isset($f['object']) ? $f['object'] : unserialize(sprintf('O:%d:"%s":0:{}', strlen($f['class']), $f['class']));
+                        $template = isset($f['object']) ? $f['object'] : unserialize(sprintf('O:%d:"%s":0:{}', \strlen($f['class']), $f['class']));
 
                         $ellipsis = 0;
                         $templateSrc = method_exists($template, 'getSourceContext') ? $template->getSourceContext()->getCode() : (method_exists($template, 'getSource') ? $template->getSource() : '');
@@ -231,7 +231,7 @@ class ExceptionCaster
                         $src = self::extractSource(file_get_contents($f['file']), $f['line'], self::$srcContext, $caller, 'php', $f['file']);
                         $srcKey .= ':'.$f['line'];
                         if ($ellipsis) {
-                            $ellipsis += 1 + strlen($f['line']);
+                            $ellipsis += 1 + \strlen($f['line']);
                         }
                     }
                     $srcAttr .= '&separator= ';
diff --git a/src/Symfony/Component/VarDumper/Caster/LinkStub.php b/src/Symfony/Component/VarDumper/Caster/LinkStub.php
index d709e262de..d232df46b0 100644
--- a/src/Symfony/Component/VarDumper/Caster/LinkStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/LinkStub.php
@@ -30,7 +30,7 @@ class LinkStub extends ConstStub
         if (null === $href) {
             $href = $label;
         }
-        if (!is_string($href)) {
+        if (!\is_string($href)) {
             return;
         }
         if (0 === strpos($href, 'file://')) {
@@ -53,11 +53,11 @@ class LinkStub extends ConstStub
             return;
         }
         if ($composerRoot = $this->getComposerRoot($href, $this->inVendor)) {
-            $this->attr['ellipsis'] = strlen($href) - strlen($composerRoot) + 1;
+            $this->attr['ellipsis'] = \strlen($href) - \strlen($composerRoot) + 1;
             $this->attr['ellipsis-type'] = 'path';
-            $this->attr['ellipsis-tail'] = 1 + ($this->inVendor ? 2 + strlen(implode(array_slice(explode(DIRECTORY_SEPARATOR, substr($href, 1 - $this->attr['ellipsis'])), 0, 2))) : 0);
-        } elseif (3 < count($ellipsis = explode(DIRECTORY_SEPARATOR, $href))) {
-            $this->attr['ellipsis'] = 2 + strlen(implode(array_slice($ellipsis, -2)));
+            $this->attr['ellipsis-tail'] = 1 + ($this->inVendor ? 2 + \strlen(implode(\array_slice(explode(DIRECTORY_SEPARATOR, substr($href, 1 - $this->attr['ellipsis'])), 0, 2))) : 0);
+        } elseif (3 < \count($ellipsis = explode(DIRECTORY_SEPARATOR, $href))) {
+            $this->attr['ellipsis'] = 2 + \strlen(implode(\array_slice($ellipsis, -2)));
             $this->attr['ellipsis-type'] = 'path';
             $this->attr['ellipsis-tail'] = 1;
         }
@@ -71,7 +71,7 @@ class LinkStub extends ConstStub
             foreach (get_declared_classes() as $class) {
                 if ('C' === $class[0] && 0 === strpos($class, 'ComposerAutoloaderInit')) {
                     $r = new \ReflectionClass($class);
-                    $v = dirname(dirname($r->getFileName()));
+                    $v = \dirname(\dirname($r->getFileName()));
                     if (file_exists($v.'/composer/installed.json')) {
                         self::$vendorRoots[] = $v.DIRECTORY_SEPARATOR;
                     }
@@ -80,7 +80,7 @@ class LinkStub extends ConstStub
         }
         $inVendor = false;
 
-        if (isset(self::$composerRoots[$dir = dirname($file)])) {
+        if (isset(self::$composerRoots[$dir = \dirname($file)])) {
             return self::$composerRoots[$dir];
         }
 
@@ -96,11 +96,11 @@ class LinkStub extends ConstStub
                 // open_basedir restriction in effect
                 break;
             }
-            if ($parent === dirname($parent)) {
+            if ($parent === \dirname($parent)) {
                 return self::$composerRoots[$dir] = false;
             }
 
-            $parent = dirname($parent);
+            $parent = \dirname($parent);
         }
 
         return self::$composerRoots[$dir] = $parent.DIRECTORY_SEPARATOR;
diff --git a/src/Symfony/Component/VarDumper/Caster/PdoCaster.php b/src/Symfony/Component/VarDumper/Caster/PdoCaster.php
index b866782477..83a001d960 100644
--- a/src/Symfony/Component/VarDumper/Caster/PdoCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/PdoCaster.php
@@ -70,7 +70,7 @@ class PdoCaster
             }
 
             try {
-                $attr[$k] = 'ERRMODE' === $k ? $errmode : $c->getAttribute(constant('PDO::ATTR_'.$k));
+                $attr[$k] = 'ERRMODE' === $k ? $errmode : $c->getAttribute(\constant('PDO::ATTR_'.$k));
                 if ($v && isset($v[$attr[$k]])) {
                     $attr[$k] = new ConstStub($v[$attr[$k]], $attr[$k]);
                 }
diff --git a/src/Symfony/Component/VarDumper/Caster/RedisCaster.php b/src/Symfony/Component/VarDumper/Caster/RedisCaster.php
index 3d7063f40a..112097fd95 100644
--- a/src/Symfony/Component/VarDumper/Caster/RedisCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/RedisCaster.php
@@ -37,7 +37,7 @@ class RedisCaster
         }
 
         $ser = $c->getOption(\Redis::OPT_SERIALIZER);
-        $retry = defined('Redis::OPT_SCAN') ? $c->getOption(\Redis::OPT_SCAN) : 0;
+        $retry = \defined('Redis::OPT_SCAN') ? $c->getOption(\Redis::OPT_SCAN) : 0;
 
         return $a + array(
             $prefix.'isConnected' => $connected,
diff --git a/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php b/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php
index 7e5f349110..703cf10226 100644
--- a/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/ReflectionCaster.php
@@ -200,7 +200,7 @@ class ReflectionCaster
 
         if ($v = $c->getStaticVariables()) {
             foreach ($v as $k => &$v) {
-                if (is_object($v)) {
+                if (\is_object($v)) {
                     $a[$prefix.'use']['$'.$k] = new CutStub($v);
                 } else {
                     $a[$prefix.'use']['$'.$k] = &$v;
diff --git a/src/Symfony/Component/VarDumper/Caster/StubCaster.php b/src/Symfony/Component/VarDumper/Caster/StubCaster.php
index 2ec096c5a8..b0bf5dc80d 100644
--- a/src/Symfony/Component/VarDumper/Caster/StubCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/StubCaster.php
@@ -30,7 +30,7 @@ class StubCaster
             $stub->cut = $c->cut;
             $stub->attr = $c->attr;
 
-            if (Stub::TYPE_REF === $c->type && !$c->class && is_string($c->value) && !preg_match('//u', $c->value)) {
+            if (Stub::TYPE_REF === $c->type && !$c->class && \is_string($c->value) && !preg_match('//u', $c->value)) {
                 $stub->type = Stub::TYPE_STRING;
                 $stub->class = Stub::STRING_BINARY;
             }
@@ -49,7 +49,7 @@ class StubCaster
     public static function cutInternals($obj, array $a, Stub $stub, $isNested)
     {
         if ($isNested) {
-            $stub->cut += count($a);
+            $stub->cut += \count($a);
 
             return array();
         }
diff --git a/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php b/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php
index b59dce52a3..c3bba2b434 100644
--- a/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php
+++ b/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php
@@ -167,7 +167,7 @@ abstract class AbstractCloner implements ClonerInterface
     public function addCasters(array $casters)
     {
         foreach ($casters as $type => $callback) {
-            $this->casters[strtolower($type)][] = is_string($callback) && false !== strpos($callback, '::') ? explode('::', $callback, 2) : $callback;
+            $this->casters[strtolower($type)][] = \is_string($callback) && false !== strpos($callback, '::') ? explode('::', $callback, 2) : $callback;
         }
     }
 
@@ -219,7 +219,7 @@ abstract class AbstractCloner implements ClonerInterface
             }
 
             if ($this->prevErrorHandler) {
-                return call_user_func($this->prevErrorHandler, $type, $msg, $file, $line, $context);
+                return \call_user_func($this->prevErrorHandler, $type, $msg, $file, $line, $context);
             }
 
             return false;
diff --git a/src/Symfony/Component/VarDumper/Cloner/Data.php b/src/Symfony/Component/VarDumper/Cloner/Data.php
index f325321234..cf5f204cd7 100644
--- a/src/Symfony/Component/VarDumper/Cloner/Data.php
+++ b/src/Symfony/Component/VarDumper/Cloner/Data.php
@@ -44,7 +44,7 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
             $item = $item->value;
         }
         if (!$item instanceof Stub) {
-            return gettype($item);
+            return \gettype($item);
         }
         if (Stub::TYPE_STRING === $item->type) {
             return 'string';
@@ -106,13 +106,13 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
 
     public function count()
     {
-        return count($this->getValue());
+        return \count($this->getValue());
     }
 
     public function getIterator()
     {
-        if (!is_array($value = $this->getValue())) {
-            throw new \LogicException(sprintf('%s object holds non-iterable type "%s".', self::class, gettype($value)));
+        if (!\is_array($value = $this->getValue())) {
+            throw new \LogicException(sprintf('%s object holds non-iterable type "%s".', self::class, \gettype($value)));
         }
 
         foreach ($value as $k => $v) {
@@ -158,11 +158,11 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
     {
         $value = $this->getValue();
 
-        if (!is_array($value)) {
+        if (!\is_array($value)) {
             return (string) $value;
         }
 
-        return sprintf('%s (count=%d)', $this->getType(), count($value));
+        return sprintf('%s (count=%d)', $this->getType(), \count($value));
     }
 
     /**
@@ -300,7 +300,7 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
                 $cursor->hardRefCount = $item->refCount;
             }
             $cursor->attr = $item->attr;
-            $type = $item->class ?: gettype($item->value);
+            $type = $item->class ?: \gettype($item->value);
             $item = $this->getStub($item->value);
         }
         if ($item instanceof Stub) {
@@ -322,7 +322,7 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
 
                 if ($cursor->stop) {
                     if ($cut >= 0) {
-                        $cut += count($children);
+                        $cut += \count($children);
                     }
                     $children = array();
                 }
@@ -351,7 +351,7 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
                             $cut = $this->dumpChildren($dumper, $cursor, $refs, $children, $cut, $item->type, null !== $item->class);
                         }
                     } elseif ($children && 0 <= $cut) {
-                        $cut += count($children);
+                        $cut += \count($children);
                     }
                     $cursor->skipChildren = false;
                     $dumper->leaveHash($cursor, $item->type, $item->class, $withChildren, $cut);
@@ -389,7 +389,7 @@ class Data implements \ArrayAccess, \Countable, \IteratorAggregate
         ++$cursor->depth;
         $cursor->hashType = $hashType;
         $cursor->hashIndex = 0;
-        $cursor->hashLength = count($children);
+        $cursor->hashLength = \count($children);
         $cursor->hashCut = $hashCut;
         foreach ($children as $key => $child) {
             $cursor->hashKeyIsBinary = isset($key[0]) && !preg_match('//u', $key);
diff --git a/src/Symfony/Component/VarDumper/Dumper/AbstractDumper.php b/src/Symfony/Component/VarDumper/Dumper/AbstractDumper.php
index 01437d94c7..abcda1af80 100644
--- a/src/Symfony/Component/VarDumper/Dumper/AbstractDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/AbstractDumper.php
@@ -49,7 +49,7 @@ abstract class AbstractDumper implements DataDumperInterface, DumperInterface
         $this->decimalPoint = localeconv();
         $this->decimalPoint = $this->decimalPoint['decimal_point'];
         $this->setOutput($output ?: static::$defaultOutput);
-        if (!$output && is_string(static::$defaultOutput)) {
+        if (!$output && \is_string(static::$defaultOutput)) {
             static::$defaultOutput = $this->outputStream;
         }
     }
@@ -65,11 +65,11 @@ abstract class AbstractDumper implements DataDumperInterface, DumperInterface
     {
         $prev = null !== $this->outputStream ? $this->outputStream : $this->lineDumper;
 
-        if (is_callable($output)) {
+        if (\is_callable($output)) {
             $this->outputStream = null;
             $this->lineDumper = $output;
         } else {
-            if (is_string($output)) {
+            if (\is_string($output)) {
                 $output = fopen($output, 'wb');
             }
             $this->outputStream = $output;
@@ -195,7 +195,7 @@ abstract class AbstractDumper implements DataDumperInterface, DumperInterface
             return $s;
         }
 
-        if (!function_exists('iconv')) {
+        if (!\function_exists('iconv')) {
             throw new \RuntimeException('Unable to convert a non-UTF-8 string to UTF-8: required function iconv() does not exist. You should install ext-iconv or symfony/polyfill-iconv.');
         }
 
diff --git a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
index f977157231..0eb90dcc06 100644
--- a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
@@ -186,7 +186,7 @@ class CliDumper extends AbstractDumper
                 unset($str[1]);
                 $str[0] .= "\n";
             }
-            $m = count($str) - 1;
+            $m = \count($str) - 1;
             $i = $lineCut = 0;
 
             if (self::DUMP_STRING_LENGTH & $this->flags) {
@@ -339,7 +339,7 @@ class CliDumper extends AbstractDumper
                     $style = 'index';
                     // no break
                 case Cursor::HASH_ASSOC:
-                    if (is_int($key)) {
+                    if (\is_int($key)) {
                         $this->line .= $this->style($style, $key).' => ';
                     } else {
                         $this->line .= $bin.'"'.$this->style($style, $key).'" => ';
@@ -418,7 +418,7 @@ class CliDumper extends AbstractDumper
         if (isset($attr['ellipsis'], $attr['ellipsis-type'])) {
             $prefix = substr($value, 0, -$attr['ellipsis']);
             if ('cli' === PHP_SAPI && 'path' === $attr['ellipsis-type'] && isset($_SERVER[$pwd = '\\' === DIRECTORY_SEPARATOR ? 'CD' : 'PWD']) && 0 === strpos($prefix, $_SERVER[$pwd])) {
-                $prefix = '.'.substr($prefix, strlen($_SERVER[$pwd]));
+                $prefix = '.'.substr($prefix, \strlen($_SERVER[$pwd]));
             }
             if (!empty($attr['ellipsis-tail'])) {
                 $prefix .= substr($value, -$attr['ellipsis'], $attr['ellipsis-tail']);
@@ -439,7 +439,7 @@ class CliDumper extends AbstractDumper
             $s = $startCchr;
             $c = $c[$i = 0];
             do {
-                $s .= isset($map[$c[$i]]) ? $map[$c[$i]] : sprintf('\x%02X', ord($c[$i]));
+                $s .= isset($map[$c[$i]]) ? $map[$c[$i]] : sprintf('\x%02X', \ord($c[$i]));
             } while (isset($c[++$i]));
 
             return $s.$endCchr;
@@ -447,12 +447,12 @@ class CliDumper extends AbstractDumper
 
         if ($this->colors) {
             if ($cchrCount && "\033" === $value[0]) {
-                $value = substr($value, strlen($startCchr));
+                $value = substr($value, \strlen($startCchr));
             } else {
                 $value = "\033[{$style}m".$value;
             }
-            if ($cchrCount && $endCchr === substr($value, -strlen($endCchr))) {
-                $value = substr($value, 0, -strlen($endCchr));
+            if ($cchrCount && $endCchr === substr($value, -\strlen($endCchr))) {
+                $value = substr($value, 0, -\strlen($endCchr));
             } else {
                 $value .= "\033[{$this->styles['default']}m";
             }
@@ -474,7 +474,7 @@ class CliDumper extends AbstractDumper
         }
         if (isset($_SERVER['argv'][1])) {
             $colors = $_SERVER['argv'];
-            $i = count($colors);
+            $i = \count($colors);
             while (--$i > 0) {
                 if (isset($colors[$i][5])) {
                     switch ($colors[$i]) {
@@ -537,7 +537,7 @@ class CliDumper extends AbstractDumper
      */
     private function hasColorSupport($stream)
     {
-        if (!is_resource($stream) || 'stream' !== get_resource_type($stream)) {
+        if (!\is_resource($stream) || 'stream' !== get_resource_type($stream)) {
             return false;
         }
 
@@ -546,18 +546,18 @@ class CliDumper extends AbstractDumper
         }
 
         if (DIRECTORY_SEPARATOR === '\\') {
-            return (function_exists('sapi_windows_vt100_support')
+            return (\function_exists('sapi_windows_vt100_support')
                 && @sapi_windows_vt100_support($stream))
                 || false !== getenv('ANSICON')
                 || 'ON' === getenv('ConEmuANSI')
                 || 'xterm' === getenv('TERM');
         }
 
-        if (function_exists('stream_isatty')) {
+        if (\function_exists('stream_isatty')) {
             return @stream_isatty($stream);
         }
 
-        if (function_exists('posix_isatty')) {
+        if (\function_exists('posix_isatty')) {
             return @posix_isatty($stream);
         }
 
diff --git a/src/Symfony/Component/VarDumper/Dumper/ContextProvider/SourceContextProvider.php b/src/Symfony/Component/VarDumper/Dumper/ContextProvider/SourceContextProvider.php
index 0c96db5258..bebd9104a1 100644
--- a/src/Symfony/Component/VarDumper/Dumper/ContextProvider/SourceContextProvider.php
+++ b/src/Symfony/Component/VarDumper/Dumper/ContextProvider/SourceContextProvider.php
@@ -74,7 +74,7 @@ final class SourceContextProvider implements ContextProviderInterface
                                 $src = explode("\n", $src);
                                 $fileExcerpt = array();
 
-                                for ($i = max($line - 3, 1), $max = min($line + 3, count($src)); $i <= $max; ++$i) {
+                                for ($i = max($line - 3, 1), $max = min($line + 3, \count($src)); $i <= $max; ++$i) {
                                     $fileExcerpt[] = '<li'.($i === $line ? ' class="selected"' : '').'><code>'.$this->htmlEncode($src[$i - 1]).'</code></li>';
                                 }
 
@@ -99,7 +99,7 @@ final class SourceContextProvider implements ContextProviderInterface
         if (null !== $this->projectDir) {
             $context['project_dir'] = $this->projectDir;
             if (0 === strpos($file, $this->projectDir)) {
-                $context['file_relative'] = ltrim(substr($file, strlen($this->projectDir)), DIRECTORY_SEPARATOR);
+                $context['file_relative'] = ltrim(substr($file, \strlen($this->projectDir)), DIRECTORY_SEPARATOR);
             }
         }
 
diff --git a/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php b/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php
index c29200bf7d..be8cf5aed6 100644
--- a/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php
@@ -827,10 +827,10 @@ EOHTML
             }
             $label = esc(substr($value, -$attr['ellipsis']));
             $style = str_replace(' title="', " title=\"$v\n", $style);
-            $v = sprintf('<span class=%s>%s</span>', $class, substr($v, 0, -strlen($label)));
+            $v = sprintf('<span class=%s>%s</span>', $class, substr($v, 0, -\strlen($label)));
 
             if (!empty($attr['ellipsis-tail'])) {
-                $tail = strlen(esc(substr($value, -$attr['ellipsis'], $attr['ellipsis-tail'])));
+                $tail = \strlen(esc(substr($value, -$attr['ellipsis'], $attr['ellipsis-tail'])));
                 $v .= sprintf('<span class=sf-dump-ellipsis>%s</span>%s', substr($label, 0, $tail), substr($label, $tail));
             } else {
                 $v .= $label;
@@ -853,7 +853,7 @@ EOHTML
                     $s .= '">';
                 }
 
-                $s .= isset($map[$c[$i]]) ? $map[$c[$i]] : sprintf('\x%02X', ord($c[$i]));
+                $s .= isset($map[$c[$i]]) ? $map[$c[$i]] : sprintf('\x%02X', \ord($c[$i]));
             } while (isset($c[++$i]));
 
             return $s.'</span>';
@@ -908,7 +908,7 @@ EOHTML
         $options = $this->extraDisplayOptions + $this->displayOptions;
 
         if ($fmt = $options['fileLinkFormat']) {
-            return is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line);
+            return \is_string($fmt) ? strtr($fmt, array('%f' => $file, '%l' => $line)) : $fmt->format($file, $line);
         }
 
         return false;
diff --git a/src/Symfony/Component/VarDumper/Exception/ThrowingCasterException.php b/src/Symfony/Component/VarDumper/Exception/ThrowingCasterException.php
index 976f4439b6..af47753ad5 100644
--- a/src/Symfony/Component/VarDumper/Exception/ThrowingCasterException.php
+++ b/src/Symfony/Component/VarDumper/Exception/ThrowingCasterException.php
@@ -21,6 +21,6 @@ class ThrowingCasterException extends \Exception
      */
     public function __construct(\Exception $prev)
     {
-        parent::__construct('Unexpected '.get_class($prev).' thrown from a caster: '.$prev->getMessage(), 0, $prev);
+        parent::__construct('Unexpected '.\get_class($prev).' thrown from a caster: '.$prev->getMessage(), 0, $prev);
     }
 }
diff --git a/src/Symfony/Component/VarDumper/Server/DumpServer.php b/src/Symfony/Component/VarDumper/Server/DumpServer.php
index dd66afa30f..6f79ca4c19 100644
--- a/src/Symfony/Component/VarDumper/Server/DumpServer.php
+++ b/src/Symfony/Component/VarDumper/Server/DumpServer.php
@@ -63,7 +63,7 @@ class DumpServer
                 continue;
             }
 
-            if (!is_array($payload) || count($payload) < 2 || !$payload[0] instanceof Data || !is_array($payload[1])) {
+            if (!\is_array($payload) || \count($payload) < 2 || !$payload[0] instanceof Data || !\is_array($payload[1])) {
                 if ($this->logger) {
                     $this->logger->warning('Invalid payload from {clientId} client. Expected an array of two elements (Data $data, array $context)', array('clientId' => $clientId));
                 }
diff --git a/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php b/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php
index 3946b2eb86..bcf55dee8b 100644
--- a/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php
+++ b/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php
@@ -48,7 +48,7 @@ trait VarDumperTestTrait
 
     private function prepareExpectation($expected, $filter)
     {
-        if (!is_string($expected)) {
+        if (!\is_string($expected)) {
             $expected = $this->getDump($expected, null, $filter);
         }
 
diff --git a/src/Symfony/Component/VarDumper/Tests/Caster/DateCasterTest.php b/src/Symfony/Component/VarDumper/Tests/Caster/DateCasterTest.php
index f6d03792b1..50b217426c 100644
--- a/src/Symfony/Component/VarDumper/Tests/Caster/DateCasterTest.php
+++ b/src/Symfony/Component/VarDumper/Tests/Caster/DateCasterTest.php
@@ -272,7 +272,7 @@ EODUMP;
 
     public function provideTimeZones()
     {
-        $xRegion = extension_loaded('intl') ? '%s' : '';
+        $xRegion = \extension_loaded('intl') ? '%s' : '';
 
         return array(
             // type 1 (UTC offset)
@@ -302,7 +302,7 @@ EODUMP;
      */
     public function testDumpPeriod($start, $interval, $end, $options, $expected)
     {
-        $p = new \DatePeriod(new \DateTime($start), new \DateInterval($interval), is_int($end) ? $end : new \DateTime($end), $options);
+        $p = new \DatePeriod(new \DateTime($start), new \DateInterval($interval), \is_int($end) ? $end : new \DateTime($end), $options);
 
         $xDump = <<<EODUMP
 DatePeriod {
@@ -318,7 +318,7 @@ EODUMP;
      */
     public function testCastPeriod($start, $interval, $end, $options, $xPeriod, $xDates)
     {
-        $p = new \DatePeriod(new \DateTime($start), new \DateInterval($interval), is_int($end) ? $end : new \DateTime($end), $options);
+        $p = new \DatePeriod(new \DateTime($start), new \DateInterval($interval), \is_int($end) ? $end : new \DateTime($end), $options);
         $stub = new Stub();
 
         $cast = DateCaster::castPeriod($p, array(), $stub, false, 0);
diff --git a/src/Symfony/Component/VarDumper/Tests/Caster/ExceptionCasterTest.php b/src/Symfony/Component/VarDumper/Tests/Caster/ExceptionCasterTest.php
index c9cc24f2df..4f9b538a0a 100644
--- a/src/Symfony/Component/VarDumper/Tests/Caster/ExceptionCasterTest.php
+++ b/src/Symfony/Component/VarDumper/Tests/Caster/ExceptionCasterTest.php
@@ -164,16 +164,16 @@ EODUMP;
      */
     public function testFrameWithTwig()
     {
-        require_once dirname(__DIR__).'/Fixtures/Twig.php';
+        require_once \dirname(__DIR__).'/Fixtures/Twig.php';
 
         $f = array(
             new FrameStub(array(
-                'file' => dirname(__DIR__).'/Fixtures/Twig.php',
+                'file' => \dirname(__DIR__).'/Fixtures/Twig.php',
                 'line' => 20,
                 'class' => '__TwigTemplate_VarDumperFixture_u75a09',
             )),
             new FrameStub(array(
-                'file' => dirname(__DIR__).'/Fixtures/Twig.php',
+                'file' => \dirname(__DIR__).'/Fixtures/Twig.php',
                 'line' => 21,
                 'class' => '__TwigTemplate_VarDumperFixture_u75a09',
                 'object' => new \__TwigTemplate_VarDumperFixture_u75a09(null, __FILE__),
diff --git a/src/Symfony/Component/VarDumper/Tests/Caster/ReflectionCasterTest.php b/src/Symfony/Component/VarDumper/Tests/Caster/ReflectionCasterTest.php
index a524451326..9c8bf6386d 100644
--- a/src/Symfony/Component/VarDumper/Tests/Caster/ReflectionCasterTest.php
+++ b/src/Symfony/Component/VarDumper/Tests/Caster/ReflectionCasterTest.php
@@ -154,7 +154,7 @@ EOTXT
 
     public function testGenerator()
     {
-        if (extension_loaded('xdebug')) {
+        if (\extension_loaded('xdebug')) {
             $this->markTestSkipped('xdebug is active');
         }
 
diff --git a/src/Symfony/Component/VarDumper/Tests/Cloner/DataTest.php b/src/Symfony/Component/VarDumper/Tests/Cloner/DataTest.php
index 83f6b60074..d10951be93 100644
--- a/src/Symfony/Component/VarDumper/Tests/Cloner/DataTest.php
+++ b/src/Symfony/Component/VarDumper/Tests/Cloner/DataTest.php
@@ -26,14 +26,14 @@ class DataTest extends TestCase
         $clonedValues = array();
 
         $this->assertInstanceOf(Data::class, $data);
-        $this->assertCount(count($values), $data);
+        $this->assertCount(\count($values), $data);
         $this->assertFalse(isset($data->{0}));
         $this->assertFalse(isset($data[0]));
 
         foreach ($data as $k => $v) {
             $this->assertTrue(isset($data->{$k}));
             $this->assertTrue(isset($data[$k]));
-            $this->assertSame(gettype($values[$k]), $data->seek($k)->getType());
+            $this->assertSame(\gettype($values[$k]), $data->seek($k)->getType());
             $this->assertSame($values[$k], $data->seek($k)->getValue());
             $this->assertSame($values[$k], $data->{$k});
             $this->assertSame($values[$k], $data[$k]);
diff --git a/src/Symfony/Component/VarDumper/VarDumper.php b/src/Symfony/Component/VarDumper/VarDumper.php
index 137c474780..30dae64316 100644
--- a/src/Symfony/Component/VarDumper/VarDumper.php
+++ b/src/Symfony/Component/VarDumper/VarDumper.php
@@ -35,7 +35,7 @@ class VarDumper
             };
         }
 
-        return call_user_func(self::$handler, $var);
+        return \call_user_func(self::$handler, $var);
     }
 
     public static function setHandler(callable $callable = null)
diff --git a/src/Symfony/Component/WebLink/HttpHeaderSerializer.php b/src/Symfony/Component/WebLink/HttpHeaderSerializer.php
index 01bb9f154b..bcc04acf23 100644
--- a/src/Symfony/Component/WebLink/HttpHeaderSerializer.php
+++ b/src/Symfony/Component/WebLink/HttpHeaderSerializer.php
@@ -39,7 +39,7 @@ final class HttpHeaderSerializer
 
             $attributesParts = array('', sprintf('rel="%s"', implode(' ', $link->getRels())));
             foreach ($link->getAttributes() as $key => $value) {
-                if (is_array($value)) {
+                if (\is_array($value)) {
                     foreach ($value as $v) {
                         $attributesParts[] = sprintf('%s="%s"', $key, $v);
                     }
@@ -47,7 +47,7 @@ final class HttpHeaderSerializer
                     continue;
                 }
 
-                if (!is_bool($value)) {
+                if (!\is_bool($value)) {
                     $attributesParts[] = sprintf('%s="%s"', $key, $value);
 
                     continue;
diff --git a/src/Symfony/Component/Workflow/Definition.php b/src/Symfony/Component/Workflow/Definition.php
index 310cec8f15..ccab6101cf 100644
--- a/src/Symfony/Component/Workflow/Definition.php
+++ b/src/Symfony/Component/Workflow/Definition.php
@@ -90,7 +90,7 @@ final class Definition
 
     private function addPlace(string $place)
     {
-        if (!count($this->places)) {
+        if (!\count($this->places)) {
             $this->initialPlace = $place;
         }
 
diff --git a/src/Symfony/Component/Workflow/Dumper/PlantUmlDumper.php b/src/Symfony/Component/Workflow/Dumper/PlantUmlDumper.php
index 2acf919ca1..84842a3955 100644
--- a/src/Symfony/Component/Workflow/Dumper/PlantUmlDumper.php
+++ b/src/Symfony/Component/Workflow/Dumper/PlantUmlDumper.php
@@ -89,7 +89,7 @@ class PlantUmlDumper implements DumperInterface
                             "$transitionEscaped --> $toEscaped",
                         );
                         foreach ($lines as $line) {
-                            if (!in_array($line, $code)) {
+                            if (!\in_array($line, $code)) {
                                 $code[] = $line;
                             }
                         }
@@ -135,12 +135,12 @@ class PlantUmlDumper implements DumperInterface
         if (isset($options['name'])) {
             $code[] = "title {$options['name']}";
         }
-        if (isset($options['skinparams']) && is_array($options['skinparams'])) {
+        if (isset($options['skinparams']) && \is_array($options['skinparams'])) {
             foreach ($options['skinparams'] as $skinparamKey => $skinparamValue) {
                 if (!$this->isWorkflowTransitionType() && 'agent' === $skinparamKey) {
                     continue;
                 }
-                if (!is_array($skinparamValue)) {
+                if (!\is_array($skinparamValue)) {
                     $code[] = "skinparam {$skinparamKey} $skinparamValue";
                     continue;
                 }
diff --git a/src/Symfony/Component/Workflow/Event/Event.php b/src/Symfony/Component/Workflow/Event/Event.php
index 8e7cbe2f21..395f2fd97b 100644
--- a/src/Symfony/Component/Workflow/Event/Event.php
+++ b/src/Symfony/Component/Workflow/Event/Event.php
@@ -43,7 +43,7 @@ class Event extends BaseEvent
         if (null === $workflow) {
             @trigger_error(sprintf('Passing only three parameters to "%s" is deprecated since Symfony 4.1. Pass a %s instance as fourth parameter instead.', __METHOD__, WorkflowInterface::class), E_USER_DEPRECATED);
             $this->workflowName = 'unnamed';
-        } elseif (is_string($workflow)) {
+        } elseif (\is_string($workflow)) {
             @trigger_error(sprintf('Passing a string as the 4th parameter of "%s()" is deprecated since Symfony 4.1. Pass a %s instance instead.', __METHOD__, WorkflowInterface::class), E_USER_DEPRECATED);
             $this->workflowName = $workflow;
         } elseif ($workflow instanceof WorkflowInterface) {
diff --git a/src/Symfony/Component/Workflow/EventListener/AuditTrailListener.php b/src/Symfony/Component/Workflow/EventListener/AuditTrailListener.php
index 83b1c5e1d8..ba56b58601 100644
--- a/src/Symfony/Component/Workflow/EventListener/AuditTrailListener.php
+++ b/src/Symfony/Component/Workflow/EventListener/AuditTrailListener.php
@@ -30,19 +30,19 @@ class AuditTrailListener implements EventSubscriberInterface
     public function onLeave(Event $event)
     {
         foreach ($event->getTransition()->getFroms() as $place) {
-            $this->logger->info(sprintf('Leaving "%s" for subject of class "%s" in workflow "%s".', $place, get_class($event->getSubject()), $event->getWorkflowName()));
+            $this->logger->info(sprintf('Leaving "%s" for subject of class "%s" in workflow "%s".', $place, \get_class($event->getSubject()), $event->getWorkflowName()));
         }
     }
 
     public function onTransition(Event $event)
     {
-        $this->logger->info(sprintf('Transition "%s" for subject of class "%s" in workflow "%s".', $event->getTransition()->getName(), get_class($event->getSubject()), $event->getWorkflowName()));
+        $this->logger->info(sprintf('Transition "%s" for subject of class "%s" in workflow "%s".', $event->getTransition()->getName(), \get_class($event->getSubject()), $event->getWorkflowName()));
     }
 
     public function onEnter(Event $event)
     {
         foreach ($event->getTransition()->getTos() as $place) {
-            $this->logger->info(sprintf('Entering "%s" for subject of class "%s" in workflow "%s".', $place, get_class($event->getSubject()), $event->getWorkflowName()));
+            $this->logger->info(sprintf('Entering "%s" for subject of class "%s" in workflow "%s".', $place, \get_class($event->getSubject()), $event->getWorkflowName()));
         }
     }
 
diff --git a/src/Symfony/Component/Workflow/EventListener/ExpressionLanguage.php b/src/Symfony/Component/Workflow/EventListener/ExpressionLanguage.php
index e1bcc7997d..6fb43077bb 100644
--- a/src/Symfony/Component/Workflow/EventListener/ExpressionLanguage.php
+++ b/src/Symfony/Component/Workflow/EventListener/ExpressionLanguage.php
@@ -41,7 +41,7 @@ class ExpressionLanguage extends BaseExpressionLanguage
 
             $errors = $variables['validator']->validate($object, null, $groups);
 
-            return 0 === count($errors);
+            return 0 === \count($errors);
         });
     }
 }
diff --git a/src/Symfony/Component/Workflow/Metadata/GetMetadataTrait.php b/src/Symfony/Component/Workflow/Metadata/GetMetadataTrait.php
index 19c5d6bf9d..a170ffacf1 100644
--- a/src/Symfony/Component/Workflow/Metadata/GetMetadataTrait.php
+++ b/src/Symfony/Component/Workflow/Metadata/GetMetadataTrait.php
@@ -43,6 +43,6 @@ trait GetMetadataTrait
             return $metadataBag[$key] ?? null;
         }
 
-        throw new InvalidArgumentException(sprintf('Could not find a MetadataBag for the subject of type "%s".', is_object($subject) ? get_class($subject) : gettype($subject)));
+        throw new InvalidArgumentException(sprintf('Could not find a MetadataBag for the subject of type "%s".', \is_object($subject) ? \get_class($subject) : \gettype($subject)));
     }
 }
diff --git a/src/Symfony/Component/Workflow/Registry.php b/src/Symfony/Component/Workflow/Registry.php
index f2117f8715..c675d8e21e 100644
--- a/src/Symfony/Component/Workflow/Registry.php
+++ b/src/Symfony/Component/Workflow/Registry.php
@@ -60,7 +60,7 @@ class Registry
         }
 
         if (!$matched) {
-            throw new InvalidArgumentException(sprintf('Unable to find a workflow for class "%s".', get_class($subject)));
+            throw new InvalidArgumentException(sprintf('Unable to find a workflow for class "%s".', \get_class($subject)));
         }
 
         return $matched;
diff --git a/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php b/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php
index 8fe5eecc4a..4f32ae5120 100644
--- a/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php
+++ b/src/Symfony/Component/Workflow/Validator/StateMachineValidator.php
@@ -24,14 +24,14 @@ class StateMachineValidator implements DefinitionValidatorInterface
         $transitionFromNames = array();
         foreach ($definition->getTransitions() as $transition) {
             // Make sure that each transition has exactly one TO
-            if (1 !== count($transition->getTos())) {
-                throw new InvalidDefinitionException(sprintf('A transition in StateMachine can only have one output. But the transition "%s" in StateMachine "%s" has %d outputs.', $transition->getName(), $name, count($transition->getTos())));
+            if (1 !== \count($transition->getTos())) {
+                throw new InvalidDefinitionException(sprintf('A transition in StateMachine can only have one output. But the transition "%s" in StateMachine "%s" has %d outputs.', $transition->getName(), $name, \count($transition->getTos())));
             }
 
             // Make sure that each transition has exactly one FROM
             $froms = $transition->getFroms();
-            if (1 !== count($froms)) {
-                throw new InvalidDefinitionException(sprintf('A transition in StateMachine can only have one input. But the transition "%s" in StateMachine "%s" has %d inputs.', $transition->getName(), $name, count($froms)));
+            if (1 !== \count($froms)) {
+                throw new InvalidDefinitionException(sprintf('A transition in StateMachine can only have one input. But the transition "%s" in StateMachine "%s" has %d inputs.', $transition->getName(), $name, \count($froms)));
             }
 
             // Enforcing uniqueness of the names of transitions starting at each node
diff --git a/src/Symfony/Component/Workflow/Validator/WorkflowValidator.php b/src/Symfony/Component/Workflow/Validator/WorkflowValidator.php
index e105224d22..703be54cb2 100644
--- a/src/Symfony/Component/Workflow/Validator/WorkflowValidator.php
+++ b/src/Symfony/Component/Workflow/Validator/WorkflowValidator.php
@@ -32,7 +32,7 @@ class WorkflowValidator implements DefinitionValidatorInterface
         $places = array_fill_keys($definition->getPlaces(), array());
         foreach ($definition->getTransitions() as $transition) {
             foreach ($transition->getFroms() as $from) {
-                if (in_array($transition->getName(), $places[$from])) {
+                if (\in_array($transition->getName(), $places[$from])) {
                     throw new InvalidDefinitionException(sprintf('All transitions for a place must have an unique name. Multiple transitions named "%s" where found for place "%s" in workflow "%s".', $transition->getName(), $from, $name));
                 }
                 $places[$from][] = $transition->getName();
@@ -44,8 +44,8 @@ class WorkflowValidator implements DefinitionValidatorInterface
         }
 
         foreach ($definition->getTransitions() as $transition) {
-            if (1 < count($transition->getTos())) {
-                throw new InvalidDefinitionException(sprintf('The marking store of workflow "%s" can not store many places. But the transition "%s" has too many output (%d). Only one is accepted.', $name, $transition->getName(), count($transition->getTos())));
+            if (1 < \count($transition->getTos())) {
+                throw new InvalidDefinitionException(sprintf('The marking store of workflow "%s" can not store many places. But the transition "%s" has too many output (%d). Only one is accepted.', $name, $transition->getName(), \count($transition->getTos())));
             }
         }
     }
diff --git a/src/Symfony/Component/Yaml/Command/LintCommand.php b/src/Symfony/Component/Yaml/Command/LintCommand.php
index 8e3a848832..56bc96fcfd 100644
--- a/src/Symfony/Component/Yaml/Command/LintCommand.php
+++ b/src/Symfony/Component/Yaml/Command/LintCommand.php
@@ -141,7 +141,7 @@ EOF
 
     private function displayTxt(SymfonyStyle $io, array $filesInfo)
     {
-        $countFiles = count($filesInfo);
+        $countFiles = \count($filesInfo);
         $erroredFiles = 0;
 
         foreach ($filesInfo as $info) {
@@ -188,7 +188,7 @@ EOF
         }
 
         foreach ($this->getDirectoryIterator($fileOrDirectory) as $file) {
-            if (!in_array($file->getExtension(), array('yml', 'yaml'))) {
+            if (!\in_array($file->getExtension(), array('yml', 'yaml'))) {
                 continue;
             }
 
@@ -229,7 +229,7 @@ EOF
         };
 
         if (null !== $this->directoryIteratorProvider) {
-            return call_user_func($this->directoryIteratorProvider, $directory, $default);
+            return \call_user_func($this->directoryIteratorProvider, $directory, $default);
         }
 
         return $default($directory);
@@ -242,7 +242,7 @@ EOF
         };
 
         if (null !== $this->isReadableProvider) {
-            return call_user_func($this->isReadableProvider, $fileOrDirectory, $default);
+            return \call_user_func($this->isReadableProvider, $fileOrDirectory, $default);
         }
 
         return $default($fileOrDirectory);
diff --git a/src/Symfony/Component/Yaml/Dumper.php b/src/Symfony/Component/Yaml/Dumper.php
index d47daa49c7..fdd34b618d 100644
--- a/src/Symfony/Component/Yaml/Dumper.php
+++ b/src/Symfony/Component/Yaml/Dumper.php
@@ -56,13 +56,13 @@ class Dumper
             $dumpObjectAsInlineMap = empty((array) $input);
         }
 
-        if ($inline <= 0 || (!is_array($input) && $dumpObjectAsInlineMap) || empty($input)) {
+        if ($inline <= 0 || (!\is_array($input) && $dumpObjectAsInlineMap) || empty($input)) {
             $output .= $prefix.Inline::dump($input, $flags);
         } else {
             $dumpAsMap = Inline::isHash($input);
 
             foreach ($input as $key => $value) {
-                if ($inline >= 1 && Yaml::DUMP_MULTI_LINE_LITERAL_BLOCK & $flags && is_string($value) && false !== strpos($value, "\n") && false === strpos($value, "\r\n")) {
+                if ($inline >= 1 && Yaml::DUMP_MULTI_LINE_LITERAL_BLOCK & $flags && \is_string($value) && false !== strpos($value, "\n") && false === strpos($value, "\r\n")) {
                     // If the first line starts with a space character, the spec requires a blockIndicationIndicator
                     // http://www.yaml.org/spec/1.2/spec.html#id2793979
                     $blockIndentationIndicator = (' ' === substr($value, 0, 1)) ? (string) $this->indentation : '';
@@ -81,7 +81,7 @@ class Dumper
                     $dumpObjectAsInlineMap = empty((array) $value);
                 }
 
-                $willBeInlined = $inline - 1 <= 0 || !is_array($value) && $dumpObjectAsInlineMap || empty($value);
+                $willBeInlined = $inline - 1 <= 0 || !\is_array($value) && $dumpObjectAsInlineMap || empty($value);
 
                 $output .= sprintf('%s%s%s%s',
                     $prefix,
diff --git a/src/Symfony/Component/Yaml/Escaper.php b/src/Symfony/Component/Yaml/Escaper.php
index 66e65bc618..4b2559ed6e 100644
--- a/src/Symfony/Component/Yaml/Escaper.php
+++ b/src/Symfony/Component/Yaml/Escaper.php
@@ -78,7 +78,7 @@ class Escaper
     {
         // Determines if a PHP value is entirely composed of a value that would
         // require single quoting in YAML.
-        if (in_array(strtolower($value), array('null', '~', 'true', 'false', 'y', 'n', 'yes', 'no', 'on', 'off'))) {
+        if (\in_array(strtolower($value), array('null', '~', 'true', 'false', 'y', 'n', 'yes', 'no', 'on', 'off'))) {
             return true;
         }
 
diff --git a/src/Symfony/Component/Yaml/Inline.php b/src/Symfony/Component/Yaml/Inline.php
index 0c0433939c..b565cde13d 100644
--- a/src/Symfony/Component/Yaml/Inline.php
+++ b/src/Symfony/Component/Yaml/Inline.php
@@ -122,7 +122,7 @@ class Inline
     public static function dump($value, int $flags = 0): string
     {
         switch (true) {
-            case is_resource($value):
+            case \is_resource($value):
                 if (Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE & $flags) {
                     throw new DumpException(sprintf('Unable to dump PHP resources in a YAML file ("%s").', get_resource_type($value)));
                 }
@@ -130,7 +130,7 @@ class Inline
                 return 'null';
             case $value instanceof \DateTimeInterface:
                 return $value->format('c');
-            case is_object($value):
+            case \is_object($value):
                 if ($value instanceof TaggedValue) {
                     return '!'.$value->getTag().' '.self::dump($value->getValue(), $flags);
                 }
@@ -154,7 +154,7 @@ class Inline
                 }
 
                 return 'null';
-            case is_array($value):
+            case \is_array($value):
                 return self::dumpArray($value, $flags);
             case null === $value:
                 return 'null';
@@ -163,13 +163,13 @@ class Inline
             case false === $value:
                 return 'false';
             case ctype_digit($value):
-                return is_string($value) ? "'$value'" : (int) $value;
+                return \is_string($value) ? "'$value'" : (int) $value;
             case is_numeric($value):
                 $locale = setlocale(LC_NUMERIC, 0);
                 if (false !== $locale) {
                     setlocale(LC_NUMERIC, 'C');
                 }
-                if (is_float($value)) {
+                if (\is_float($value)) {
                     $repr = (string) $value;
                     if (is_infinite($value)) {
                         $repr = str_ireplace('INF', '.Inf', $repr);
@@ -178,7 +178,7 @@ class Inline
                         $repr = '!!float '.$repr;
                     }
                 } else {
-                    $repr = is_string($value) ? "'$value'" : (string) $value;
+                    $repr = \is_string($value) ? "'$value'" : (string) $value;
                 }
                 if (false !== $locale) {
                     setlocale(LC_NUMERIC, $locale);
@@ -263,7 +263,7 @@ class Inline
      */
     public static function parseScalar(string $scalar, int $flags = 0, array $delimiters = null, int &$i = 0, bool $evaluate = true, array $references = array())
     {
-        if (in_array($scalar[$i], array('"', "'"))) {
+        if (\in_array($scalar[$i], array('"', "'"))) {
             // quoted scalar
             $output = self::parseQuotedScalar($scalar, $i);
 
@@ -272,7 +272,7 @@ class Inline
                 if ('' === $tmp) {
                     throw new ParseException(sprintf('Unexpected end of line, expected one of "%s".', implode($delimiters)), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                 }
-                if (!in_array($tmp[0], $delimiters)) {
+                if (!\in_array($tmp[0], $delimiters)) {
                     throw new ParseException(sprintf('Unexpected characters (%s).', substr($scalar, $i)), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
                 }
             }
@@ -280,7 +280,7 @@ class Inline
             // "normal" string
             if (!$delimiters) {
                 $output = substr($scalar, $i);
-                $i += strlen($output);
+                $i += \strlen($output);
 
                 // remove comments
                 if (Parser::preg_match('/[ \t]+#/', $output, $match, PREG_OFFSET_CAPTURE)) {
@@ -288,7 +288,7 @@ class Inline
                 }
             } elseif (Parser::preg_match('/^(.*?)('.implode('|', $delimiters).')/', substr($scalar, $i), $match)) {
                 $output = $match[1];
-                $i += strlen($output);
+                $i += \strlen($output);
                 $output = trim($output);
             } else {
                 throw new ParseException(sprintf('Malformed inline YAML string: %s.', $scalar), self::$parsedLineNumber + 1, null, self::$parsedFilename);
@@ -318,7 +318,7 @@ class Inline
             throw new ParseException(sprintf('Malformed inline YAML string: %s.', substr($scalar, $i)), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
         }
 
-        $output = substr($match[0], 1, strlen($match[0]) - 2);
+        $output = substr($match[0], 1, \strlen($match[0]) - 2);
 
         $unescaper = new Unescaper();
         if ('"' == $scalar[$i]) {
@@ -327,7 +327,7 @@ class Inline
             $output = $unescaper->unescapeSingleQuotedString($output);
         }
 
-        $i += strlen($match[0]);
+        $i += \strlen($match[0]);
 
         return $output;
     }
@@ -340,7 +340,7 @@ class Inline
     private static function parseSequence(string $sequence, int $flags, int &$i = 0, array $references = array()): array
     {
         $output = array();
-        $len = strlen($sequence);
+        $len = \strlen($sequence);
         ++$i;
 
         // [foo, bar, ...]
@@ -365,11 +365,11 @@ class Inline
                     $value = self::parseMapping($sequence, $flags, $i, $references);
                     break;
                 default:
-                    $isQuoted = in_array($sequence[$i], array('"', "'"));
+                    $isQuoted = \in_array($sequence[$i], array('"', "'"));
                     $value = self::parseScalar($sequence, $flags, array(',', ']'), $i, null === $tag, $references);
 
                     // the value can be an array if a reference has been resolved to an array var
-                    if (is_string($value) && !$isQuoted && false !== strpos($value, ': ')) {
+                    if (\is_string($value) && !$isQuoted && false !== strpos($value, ': ')) {
                         // embedded mapping?
                         try {
                             $pos = 0;
@@ -404,7 +404,7 @@ class Inline
     private static function parseMapping(string $mapping, int $flags, int &$i = 0, array $references = array())
     {
         $output = array();
-        $len = strlen($mapping);
+        $len = \strlen($mapping);
         ++$i;
         $allowOverwrite = false;
 
@@ -425,7 +425,7 @@ class Inline
 
             // key
             $offsetBeforeKeyParsing = $i;
-            $isKeyQuoted = in_array($mapping[$i], array('"', "'"), true);
+            $isKeyQuoted = \in_array($mapping[$i], array('"', "'"), true);
             $key = self::parseScalar($mapping, $flags, array(':', ' '), $i, false, array());
 
             if ($offsetBeforeKeyParsing === $i) {
@@ -439,12 +439,12 @@ class Inline
             if (!$isKeyQuoted) {
                 $evaluatedKey = self::evaluateScalar($key, $flags, $references);
 
-                if ('' !== $key && $evaluatedKey !== $key && !is_string($evaluatedKey) && !is_int($evaluatedKey)) {
+                if ('' !== $key && $evaluatedKey !== $key && !\is_string($evaluatedKey) && !\is_int($evaluatedKey)) {
                     throw new ParseException('Implicit casting of incompatible mapping keys to strings is not supported. Quote your evaluable mapping keys instead.', self::$parsedLineNumber + 1, $mapping);
                 }
             }
 
-            if (!$isKeyQuoted && (!isset($mapping[$i + 1]) || !in_array($mapping[$i + 1], array(' ', ',', '[', ']', '{', '}'), true))) {
+            if (!$isKeyQuoted && (!isset($mapping[$i + 1]) || !\in_array($mapping[$i + 1], array(' ', ',', '[', ']', '{', '}'), true))) {
                 throw new ParseException('Colons must be followed by a space or an indication character (i.e. " ", ",", "[", "]", "{", "}").', self::$parsedLineNumber + 1, $mapping);
             }
 
@@ -588,8 +588,8 @@ class Inline
                     case 0 === strpos($scalar, '!php/const'):
                         if (self::$constantSupport) {
                             $i = 0;
-                            if (defined($const = self::parseScalar(substr($scalar, 11), 0, null, $i, false))) {
-                                return constant($const);
+                            if (\defined($const = self::parseScalar(substr($scalar, 11), 0, null, $i, false))) {
+                                return \constant($const);
                             }
 
                             throw new ParseException(sprintf('The constant "%s" is not defined.', $const), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
@@ -668,7 +668,7 @@ class Inline
         $nextOffset += strspn($value, ' ', $nextOffset);
 
         // Is followed by a scalar and is a built-in tag
-        if ($tag && (!isset($value[$nextOffset]) || !in_array($value[$nextOffset], array('[', '{'), true)) && ('!' === $tag[0] || 'str' === $tag || 'php/const' === $tag || 'php/object' === $tag)) {
+        if ($tag && (!isset($value[$nextOffset]) || !\in_array($value[$nextOffset], array('[', '{'), true)) && ('!' === $tag[0] || 'str' === $tag || 'php/const' === $tag || 'php/object' === $tag)) {
             // Manage in {@link self::evaluateScalar()}
             return null;
         }
@@ -691,8 +691,8 @@ class Inline
     {
         $parsedBinaryData = self::parseScalar(preg_replace('/\s/', '', $scalar));
 
-        if (0 !== (strlen($parsedBinaryData) % 4)) {
-            throw new ParseException(sprintf('The normalized base64 encoded data (data without whitespace characters) length must be a multiple of four (%d bytes given).', strlen($parsedBinaryData)), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
+        if (0 !== (\strlen($parsedBinaryData) % 4)) {
+            throw new ParseException(sprintf('The normalized base64 encoded data (data without whitespace characters) length must be a multiple of four (%d bytes given).', \strlen($parsedBinaryData)), self::$parsedLineNumber + 1, $scalar, self::$parsedFilename);
         }
 
         if (!Parser::preg_match('#^[A-Z0-9+/]+={0,2}$#i', $parsedBinaryData)) {
diff --git a/src/Symfony/Component/Yaml/Parser.php b/src/Symfony/Component/Yaml/Parser.php
index 7caedbeabe..35e7443d13 100644
--- a/src/Symfony/Component/Yaml/Parser.php
+++ b/src/Symfony/Component/Yaml/Parser.php
@@ -126,7 +126,7 @@ class Parser
         $this->locallySkippedLineNumbers = array();
 
         if (null === $this->totalNumberOfLines) {
-            $this->totalNumberOfLines = count($this->lines);
+            $this->totalNumberOfLines = \count($this->lines);
         }
 
         if (!$this->moveToNextLine()) {
@@ -191,7 +191,7 @@ class Parser
                         // this is a compact notation element, add to next block and parse
                         $block = $values['value'];
                         if ($this->isNextLineIndented()) {
-                            $block .= "\n".$this->getNextEmbedBlock($this->getCurrentLineIndentation() + strlen($values['leadspaces']) + 1);
+                            $block .= "\n".$this->getNextEmbedBlock($this->getCurrentLineIndentation() + \strlen($values['leadspaces']) + 1);
                         }
 
                         $data[] = $this->parseBlock($this->getRealCurrentLineNb(), $block, $flags);
@@ -204,7 +204,7 @@ class Parser
                 }
             } elseif (
                 self::preg_match('#^(?P<key>(?:![^\s]++\s++)?(?:'.Inline::REGEX_QUOTED_STRING.'|(?:!?!php/const:)?[^ \'"\[\{!].*?)) *\:(\s++(?P<value>.+))?$#u', rtrim($this->currentLine), $values)
-                && (false === strpos($values['key'], ' #') || in_array($values['key'][0], array('"', "'")))
+                && (false === strpos($values['key'], ' #') || \in_array($values['key'][0], array('"', "'")))
             ) {
                 if ($context && 'sequence' == $context) {
                     throw new ParseException('You cannot define a mapping item when in a sequence', $this->currentLineNb + 1, $this->currentLine, $this->filename);
@@ -220,12 +220,12 @@ class Parser
                     throw $e;
                 }
 
-                if (!is_string($key) && !is_int($key)) {
+                if (!\is_string($key) && !\is_int($key)) {
                     throw new ParseException(sprintf('%s keys are not supported. Quote your evaluable mapping keys instead.', is_numeric($key) ? 'Numeric' : 'Non-string'), $this->getRealCurrentLineNb() + 1, $this->currentLine);
                 }
 
                 // Convert float keys to strings, to avoid being converted to integers by PHP
-                if (is_float($key)) {
+                if (\is_float($key)) {
                     $key = (string) $key;
                 }
 
@@ -244,7 +244,7 @@ class Parser
                             $refValue = (array) $refValue;
                         }
 
-                        if (!is_array($refValue)) {
+                        if (!\is_array($refValue)) {
                             throw new ParseException('YAML merge keys used with a scalar value instead of an array.', $this->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
                         }
 
@@ -261,7 +261,7 @@ class Parser
                             $parsed = (array) $parsed;
                         }
 
-                        if (!is_array($parsed)) {
+                        if (!\is_array($parsed)) {
                             throw new ParseException('YAML merge keys used with a scalar value instead of an array.', $this->getRealCurrentLineNb() + 1, $this->currentLine, $this->filename);
                         }
 
@@ -274,7 +274,7 @@ class Parser
                                     $parsedItem = (array) $parsedItem;
                                 }
 
-                                if (!is_array($parsedItem)) {
+                                if (!\is_array($parsedItem)) {
                                     throw new ParseException('Merge items must be arrays.', $this->getRealCurrentLineNb() + 1, $parsedItem, $this->filename);
                                 }
 
@@ -357,7 +357,7 @@ class Parser
                 }
 
                 // 1-liner optionally followed by newline(s)
-                if (is_string($value) && $this->lines[0] === trim($value)) {
+                if (\is_string($value) && $this->lines[0] === trim($value)) {
                     try {
                         $value = Inline::parse($this->lines[0], $flags, $this->refs);
                     } catch (ParseException $e) {
@@ -420,7 +420,7 @@ class Parser
             $data = new TaggedValue($tag, $data);
         }
 
-        if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && !is_object($data) && 'mapping' === $context) {
+        if (Yaml::PARSE_OBJECT_FOR_MAP & $flags && !\is_object($data) && 'mapping' === $context) {
             $object = new \stdClass();
 
             foreach ($data as $key => $value) {
@@ -483,7 +483,7 @@ class Parser
      */
     private function getCurrentLineIndentation(): int
     {
-        return strlen($this->currentLine) - strlen(ltrim($this->currentLine, ' '));
+        return \strlen($this->currentLine) - \strlen(ltrim($this->currentLine, ' '));
     }
 
     /**
@@ -619,7 +619,7 @@ class Parser
      */
     private function moveToNextLine(): bool
     {
-        if ($this->currentLineNb >= count($this->lines) - 1) {
+        if ($this->currentLineNb >= \count($this->lines) - 1) {
             return false;
         }
 
@@ -713,7 +713,7 @@ class Parser
                 }
             }
 
-            for ($i = 0, $linesCount = count($lines), $previousLineBlank = false; $i < $linesCount; ++$i) {
+            for ($i = 0, $linesCount = \count($lines), $previousLineBlank = false; $i < $linesCount; ++$i) {
                 if ('' === $lines[$i]) {
                     $value .= "\n";
                     $previousLineBlank = true;
@@ -730,7 +730,7 @@ class Parser
 
             $parsedValue = Inline::parse($value, $flags, $this->refs);
 
-            if ('mapping' === $context && is_string($parsedValue) && '"' !== $value[0] && "'" !== $value[0] && '[' !== $value[0] && '{' !== $value[0] && '!' !== $value[0] && false !== strpos($parsedValue, ': ')) {
+            if ('mapping' === $context && \is_string($parsedValue) && '"' !== $value[0] && "'" !== $value[0] && '[' !== $value[0] && '{' !== $value[0] && '!' !== $value[0] && false !== strpos($parsedValue, ': ')) {
                 throw new ParseException('A colon cannot be used in an unquoted mapping value.', $this->getRealCurrentLineNb() + 1, $value, $this->filename);
             }
 
@@ -774,7 +774,7 @@ class Parser
         // determine indentation if not specified
         if (0 === $indentation) {
             if (self::preg_match('/^ +/', $this->currentLine, $matches)) {
-                $indentation = strlen($matches[0]);
+                $indentation = \strlen($matches[0]);
             }
         }
 
@@ -787,7 +787,7 @@ class Parser
                     self::preg_match($pattern, $this->currentLine, $matches)
                 )
             ) {
-                if ($isCurrentLineBlank && strlen($this->currentLine) > $indentation) {
+                if ($isCurrentLineBlank && \strlen($this->currentLine) > $indentation) {
                     $blockLines[] = substr($this->currentLine, $indentation);
                 } elseif ($isCurrentLineBlank) {
                     $blockLines[] = '';
@@ -817,7 +817,7 @@ class Parser
             $previousLineIndented = false;
             $previousLineBlank = false;
 
-            for ($i = 0, $blockLinesCount = count($blockLines); $i < $blockLinesCount; ++$i) {
+            for ($i = 0, $blockLinesCount = \count($blockLines); $i < $blockLinesCount; ++$i) {
                 if ('' === $blockLines[$i]) {
                     $text .= "\n";
                     $previousLineIndented = false;
diff --git a/src/Symfony/Component/Yaml/Unescaper.php b/src/Symfony/Component/Yaml/Unescaper.php
index 78b8bacada..9c3a19ec5e 100644
--- a/src/Symfony/Component/Yaml/Unescaper.php
+++ b/src/Symfony/Component/Yaml/Unescaper.php
@@ -124,15 +124,15 @@ class Unescaper
     private static function utf8chr(int $c): string
     {
         if (0x80 > $c %= 0x200000) {
-            return chr($c);
+            return \chr($c);
         }
         if (0x800 > $c) {
-            return chr(0xC0 | $c >> 6).chr(0x80 | $c & 0x3F);
+            return \chr(0xC0 | $c >> 6).\chr(0x80 | $c & 0x3F);
         }
         if (0x10000 > $c) {
-            return chr(0xE0 | $c >> 12).chr(0x80 | $c >> 6 & 0x3F).chr(0x80 | $c & 0x3F);
+            return \chr(0xE0 | $c >> 12).\chr(0x80 | $c >> 6 & 0x3F).\chr(0x80 | $c & 0x3F);
         }
 
-        return chr(0xF0 | $c >> 18).chr(0x80 | $c >> 12 & 0x3F).chr(0x80 | $c >> 6 & 0x3F).chr(0x80 | $c & 0x3F);
+        return \chr(0xF0 | $c >> 18).\chr(0x80 | $c >> 12 & 0x3F).\chr(0x80 | $c >> 6 & 0x3F).\chr(0x80 | $c & 0x3F);
     }
 }