diff --git a/src/Symfony/Component/BrowserKit/Client.php b/src/Symfony/Component/BrowserKit/Client.php
index 1370f1c838..22c889ecd7 100644
--- a/src/Symfony/Component/BrowserKit/Client.php
+++ b/src/Symfony/Component/BrowserKit/Client.php
@@ -136,7 +136,7 @@ abstract class Client
      */
     public function getServerParameter($key, $default = '')
     {
-        return (isset($this->server[$key])) ? $this->server[$key] : $default;
+        return isset($this->server[$key]) ? $this->server[$key] : $default;
     }
 
     /**
diff --git a/src/Symfony/Component/Console/Helper/TableHelper.php b/src/Symfony/Component/Console/Helper/TableHelper.php
index 00814ecdd9..16aede1248 100644
--- a/src/Symfony/Component/Console/Helper/TableHelper.php
+++ b/src/Symfony/Component/Console/Helper/TableHelper.php
@@ -111,7 +111,7 @@ class TableHelper extends Helper
 
             default:
                 throw new \InvalidArgumentException(sprintf('Invalid table layout "%s".', $layout));
-        };
+        }
 
         return $this;
     }
diff --git a/src/Symfony/Component/Console/Output/ConsoleOutput.php b/src/Symfony/Component/Console/Output/ConsoleOutput.php
index 8e1f360141..f666c793e2 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
             PHP_OS,
         );
 
-        return false !== stristr(implode(';', $checks), 'OS400');
+        return false !== stripos(implode(';', $checks), 'OS400');
     }
 
     /**
diff --git a/src/Symfony/Component/DependencyInjection/Container.php b/src/Symfony/Component/DependencyInjection/Container.php
index fb0e31911b..75de9c4fde 100644
--- a/src/Symfony/Component/DependencyInjection/Container.php
+++ b/src/Symfony/Component/DependencyInjection/Container.php
@@ -536,6 +536,6 @@ class Container implements IntrospectableContainerInterface
      */
     public static function underscore($id)
     {
-        return strtolower(preg_replace(array('/([A-Z]+)([A-Z][a-z])/', '/([a-z\d])([A-Z])/'), array('\\1_\\2', '\\1_\\2'), strtr($id, '_', '.')));
+        return strtolower(preg_replace(array('/([A-Z]+)([A-Z][a-z])/', '/([a-z\d])([A-Z])/'), array('\\1_\\2', '\\1_\\2'), str_replace('_', '.', $id)));
     }
 }
diff --git a/src/Symfony/Component/DependencyInjection/Extension/Extension.php b/src/Symfony/Component/DependencyInjection/Extension/Extension.php
index f8e058bafd..20ea1002cb 100644
--- a/src/Symfony/Component/DependencyInjection/Extension/Extension.php
+++ b/src/Symfony/Component/DependencyInjection/Extension/Extension.php
@@ -91,9 +91,7 @@ abstract class Extension implements ExtensionInterface, ConfigurationExtensionIn
             $container->addResource(new FileResource($r->getFileName()));
 
             if (!method_exists($class, '__construct')) {
-                $configuration = new $class();
-
-                return $configuration;
+                return new $class();
             }
         }
     }
diff --git a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
index 95470ce7f7..b268cb9904 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/XmlFileLoader.php
@@ -91,8 +91,9 @@ class XmlFileLoader extends FileLoader
             return;
         }
 
+        $defaultDirectory = dirname($file);
         foreach ($imports as $import) {
-            $this->setCurrentDir(dirname($file));
+            $this->setCurrentDir($defaultDirectory);
             $this->import((string) $import['resource'], null, (bool) $import->getAttributeAsPhp('ignore-errors'), $file);
         }
     }
diff --git a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
index 440b46fa80..91adf2b78d 100644
--- a/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
+++ b/src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php
@@ -94,12 +94,13 @@ class YamlFileLoader extends FileLoader
             throw new InvalidArgumentException(sprintf('The "imports" key should contain an array in %s. Check your YAML syntax.', $file));
         }
 
+        $defaultDirectory = dirname($file);
         foreach ($content['imports'] as $import) {
             if (!is_array($import)) {
                 throw new InvalidArgumentException(sprintf('The values in the "imports" key should be arrays in %s. Check your YAML syntax.', $file));
             }
 
-            $this->setCurrentDir(dirname($file));
+            $this->setCurrentDir($defaultDirectory);
             $this->import($import['resource'], null, isset($import['ignore_errors']) ? (bool) $import['ignore_errors'] : false, $file);
         }
     }
diff --git a/src/Symfony/Component/Filesystem/Filesystem.php b/src/Symfony/Component/Filesystem/Filesystem.php
index 3ff72d28fb..4fe9f3485e 100644
--- a/src/Symfony/Component/Filesystem/Filesystem.php
+++ b/src/Symfony/Component/Filesystem/Filesystem.php
@@ -431,7 +431,7 @@ class Filesystem
         return strspn($file, '/\\', 0, 1)
             || (strlen($file) > 3 && ctype_alpha($file[0])
                 && substr($file, 1, 1) === ':'
-                && (strspn($file, '/\\', 2, 1))
+                && strspn($file, '/\\', 2, 1)
             )
             || null !== parse_url($file, PHP_URL_SCHEME)
         ;
diff --git a/src/Symfony/Component/HttpFoundation/HeaderBag.php b/src/Symfony/Component/HttpFoundation/HeaderBag.php
index bcf143099e..761be9673f 100644
--- a/src/Symfony/Component/HttpFoundation/HeaderBag.php
+++ b/src/Symfony/Component/HttpFoundation/HeaderBag.php
@@ -113,7 +113,7 @@ class HeaderBag implements \IteratorAggregate, \Countable
      */
     public function get($key, $default = null, $first = true)
     {
-        $key = strtr(strtolower($key), '_', '-');
+        $key = str_replace('_', '-', strtolower($key));
 
         if (!array_key_exists($key, $this->headers)) {
             if (null === $default) {
@@ -139,7 +139,7 @@ class HeaderBag implements \IteratorAggregate, \Countable
      */
     public function set($key, $values, $replace = true)
     {
-        $key = strtr(strtolower($key), '_', '-');
+        $key = str_replace('_', '-', strtolower($key));
 
         $values = array_values((array) $values);
 
@@ -163,7 +163,7 @@ class HeaderBag implements \IteratorAggregate, \Countable
      */
     public function has($key)
     {
-        return array_key_exists(strtr(strtolower($key), '_', '-'), $this->headers);
+        return array_key_exists(str_replace('_', '-', strtolower($key)), $this->headers);
     }
 
     /**
@@ -186,7 +186,7 @@ class HeaderBag implements \IteratorAggregate, \Countable
      */
     public function remove($key)
     {
-        $key = strtr(strtolower($key), '_', '-');
+        $key = str_replace('_', '-', strtolower($key));
 
         unset($this->headers[$key]);
 
diff --git a/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php b/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php
index a0a3f63080..37635c2e63 100644
--- a/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php
+++ b/src/Symfony/Component/HttpFoundation/ResponseHeaderBag.php
@@ -99,7 +99,7 @@ class ResponseHeaderBag extends HeaderBag
     {
         parent::set($key, $values, $replace);
 
-        $uniqueKey = strtr(strtolower($key), '_', '-');
+        $uniqueKey = str_replace('_', '-', strtolower($key));
         $this->headerNames[$uniqueKey] = $key;
 
         // ensure the cache-control header has sensible defaults
@@ -118,7 +118,7 @@ class ResponseHeaderBag extends HeaderBag
     {
         parent::remove($key);
 
-        $uniqueKey = strtr(strtolower($key), '_', '-');
+        $uniqueKey = str_replace('_', '-', strtolower($key));
         unset($this->headerNames[$uniqueKey]);
 
         if ('cache-control' === $uniqueKey) {
diff --git a/src/Symfony/Component/HttpKernel/Bundle/Bundle.php b/src/Symfony/Component/HttpKernel/Bundle/Bundle.php
index 8437af995a..9082b3e304 100644
--- a/src/Symfony/Component/HttpKernel/Bundle/Bundle.php
+++ b/src/Symfony/Component/HttpKernel/Bundle/Bundle.php
@@ -181,7 +181,7 @@ abstract class Bundle extends ContainerAware implements BundleInterface
         foreach ($finder as $file) {
             $ns = $prefix;
             if ($relativePath = $file->getRelativePath()) {
-                $ns .= '\\'.strtr($relativePath, '/', '\\');
+                $ns .= '\\'.str_replace('/', '\\', $relativePath);
             }
             $r = new \ReflectionClass($ns.'\\'.$file->getBasename('.php'));
             if ($r->isSubclassOf('Symfony\\Component\\Console\\Command\\Command') && !$r->isAbstract() && !$r->getConstructor()->getNumberOfRequiredParameters()) {
diff --git a/src/Symfony/Component/HttpKernel/HttpCache/Store.php b/src/Symfony/Component/HttpKernel/HttpCache/Store.php
index 41cfa86f53..c37cc459ea 100644
--- a/src/Symfony/Component/HttpKernel/HttpCache/Store.php
+++ b/src/Symfony/Component/HttpKernel/HttpCache/Store.php
@@ -38,10 +38,8 @@ class Store implements StoreInterface
     public function __construct($root)
     {
         $this->root = $root;
-        if (!is_dir($this->root)) {
-            if (false === @mkdir($this->root, 0777, true) && !is_dir($this->root)) {
-                throw new \RuntimeException(sprintf('Unable to create the store directory (%s).', $this->root));
-            }
+        if (!is_dir($this->root) && !@mkdir($this->root, 0777, true) && !is_dir($this->root)) {
+            throw new \RuntimeException(sprintf('Unable to create the store directory (%s).', $this->root));
         }
         $this->keyCache = new \SplObjectStorage();
         $this->locks = array();
@@ -249,10 +247,8 @@ class Store implements StoreInterface
             }
         }
 
-        if ($modified) {
-            if (false === $this->save($key, serialize($entries))) {
-                throw new \RuntimeException('Unable to store the metadata.');
-            }
+        if ($modified && false === $this->save($key, serialize($entries))) {
+            throw new \RuntimeException('Unable to store the metadata.');
         }
     }
 
@@ -273,7 +269,7 @@ class Store implements StoreInterface
         }
 
         foreach (preg_split('/[\s,]+/', $vary) as $header) {
-            $key = strtr(strtolower($header), '_', '-');
+            $key = str_replace('_', '-', strtolower($header));
             $v1 = isset($env1[$key]) ? $env1[$key] : null;
             $v2 = isset($env2[$key]) ? $env2[$key] : null;
             if ($v1 !== $v2) {
diff --git a/src/Symfony/Component/HttpKernel/Profiler/PdoProfilerStorage.php b/src/Symfony/Component/HttpKernel/Profiler/PdoProfilerStorage.php
index a545e6b44b..da50cedb15 100644
--- a/src/Symfony/Component/HttpKernel/Profiler/PdoProfilerStorage.php
+++ b/src/Symfony/Component/HttpKernel/Profiler/PdoProfilerStorage.php
@@ -187,9 +187,8 @@ abstract class PdoProfilerStorage implements ProfilerStorageInterface
             $stmt->bindValue($arg, $val, is_int($val) ? \PDO::PARAM_INT : \PDO::PARAM_STR);
         }
         $stmt->execute();
-        $return = $stmt->fetchAll(\PDO::FETCH_ASSOC);
 
-        return $return;
+        return $stmt->fetchAll(\PDO::FETCH_ASSOC);
     }
 
     protected function close($db)
diff --git a/src/Symfony/Component/HttpKernel/UriSigner.php b/src/Symfony/Component/HttpKernel/UriSigner.php
index 5a96ef2228..b56da28d3e 100644
--- a/src/Symfony/Component/HttpKernel/UriSigner.php
+++ b/src/Symfony/Component/HttpKernel/UriSigner.php
@@ -51,7 +51,7 @@ class UriSigner
 
         $uri = $this->buildUrl($url, $params);
 
-        return $uri.(false === (strpos($uri, '?')) ? '?' : '&').'_hash='.$this->computeHash($uri);
+        return $uri.(false === strpos($uri, '?') ? '?' : '&').'_hash='.$this->computeHash($uri);
     }
 
     /**
diff --git a/src/Symfony/Component/PropertyAccess/PropertyAccessor.php b/src/Symfony/Component/PropertyAccess/PropertyAccessor.php
index 5270df26f3..3b9b49490d 100644
--- a/src/Symfony/Component/PropertyAccess/PropertyAccessor.php
+++ b/src/Symfony/Component/PropertyAccess/PropertyAccessor.php
@@ -442,11 +442,11 @@ class PropertyAccessor implements PropertyAccessorInterface
             }
 
             foreach ($itemToRemove as $item) {
-                call_user_func(array($object, $access[self::ACCESS_REMOVER]), $item);
+                $object->{$access[self::ACCESS_REMOVER]}($item);
             }
 
             foreach ($itemsToAdd as $item) {
-                call_user_func(array($object, $access[self::ACCESS_ADDER]), $item);
+                $object->{$access[self::ACCESS_ADDER]}($item);
             }
         } elseif (!$access[self::ACCESS_HAS_PROPERTY] && property_exists($object, $property)) {
             // Needed to support \stdClass instances. We need to explicitly
diff --git a/src/Symfony/Component/Security/Http/Firewall/DigestAuthenticationListener.php b/src/Symfony/Component/Security/Http/Firewall/DigestAuthenticationListener.php
index 5e1159f733..4e5766756f 100644
--- a/src/Symfony/Component/Security/Http/Firewall/DigestAuthenticationListener.php
+++ b/src/Symfony/Component/Security/Http/Firewall/DigestAuthenticationListener.php
@@ -172,10 +172,8 @@ class DigestData
             throw new BadCredentialsException(sprintf('Missing mandatory digest value; received header "%s" (%s)', $this->header, implode(', ', $keys)));
         }
 
-        if ('auth' === $this->elements['qop']) {
-            if (!isset($this->elements['nc']) || !isset($this->elements['cnonce'])) {
-                throw new BadCredentialsException(sprintf('Missing mandatory digest value; received header "%s"', $this->header));
-            }
+        if ('auth' === $this->elements['qop'] && !isset($this->elements['nc'], $this->elements['cnonce'])) {
+            throw new BadCredentialsException(sprintf('Missing mandatory digest value; received header "%s"', $this->header));
         }
 
         if ($expectedRealm !== $this->elements['realm']) {
diff --git a/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php b/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
index 4b42a92ee9..ba63a4c530 100644
--- a/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
+++ b/src/Symfony/Component/Translation/Dumper/IcuResFileDumper.php
@@ -30,8 +30,8 @@ class IcuResFileDumper implements DumperInterface
         }
 
         // save a file for each domain
+        $file = $messages->getLocale().'.'.$this->getExtension();
         foreach ($messages->getDomains() as $domain) {
-            $file = $messages->getLocale().'.'.$this->getExtension();
             $path = $options['path'].'/'.$domain.'/';
 
             if (!is_dir($path) && !@mkdir($path) && !is_dir($path)) {
diff --git a/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php b/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php
index 1ebb68a49d..6275d1c547 100644
--- a/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php
+++ b/src/Symfony/Component/Validator/Mapping/Loader/XmlFileLoader.php
@@ -190,7 +190,7 @@ class XmlFileLoader extends FileLoader
      */
     private function loadClassMetadataFromXml(ClassMetadata $metadata, $classDescription)
     {
-        foreach ($classDescription->{'group-sequence-provider'} as $_) {
+        if (count($classDescription->{'group-sequence-provider'}) > 0) {
             $metadata->setGroupSequenceProvider(true);
         }