[DI] Added safeguards against invalid config in the YamlFileLoader

Exceptions explaining the mistake are better than fatal errors or weird
notices appearing when trying to deal with such invalid data.
Closes #11333

src/Symfony/Component/DependencyInjection/Loader/YamlFileLoader.php

@@ -55,6 +55,10 @@ class YamlFileLoader extends FileLoader
 
         // parameters
         if (isset($content['parameters'])) {
+            if (!is_array($content['parameters'])) {
+                throw new InvalidArgumentException(sprintf('The "parameters" key should contain an array in %s. Check your YAML syntax.', $file));
+            }
+
             foreach ($content['parameters'] as $key => $value) {
                 $this->container->setParameter($key, $this->resolveServices($value));
             }
@@ -92,7 +96,15 @@ class YamlFileLoader extends FileLoader
             return;
         }
 
+        if (!is_array($content['imports'])) {
+            throw new InvalidArgumentException(sprintf('The "imports" key should contain an array in %s. Check your YAML syntax.', $file));
+        }
+
         foreach ($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));
             $this->import($import['resource'], null, isset($import['ignore_errors']) ? (bool) $import['ignore_errors'] : false, $file);
         }
@@ -110,6 +122,10 @@ class YamlFileLoader extends FileLoader
             return;
         }
 
+        if (!is_array($content['services'])) {
+            throw new InvalidArgumentException(sprintf('The "services" key should contain an array in %s. Check your YAML syntax.', $file));
+        }
+
         foreach ($content['services'] as $id => $service) {
             $this->parseDefinition($id, $service, $file);
         }
@@ -130,7 +146,13 @@ class YamlFileLoader extends FileLoader
             $this->container->setAlias($id, substr($service, 1));
 
             return;
-        } elseif (isset($service['alias'])) {
+        }
+
+        if (!is_array($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, $file));
+        }
+
+        if (isset($service['alias'])) {
             $public = !array_key_exists('public', $service) || (bool) $service['public'];
             $this->container->setAlias($id, new Alias($service['alias'], $public));
 
@@ -204,6 +226,10 @@ class YamlFileLoader extends FileLoader
         }
 
         if (isset($service['calls'])) {
+            if (!is_array($service['calls'])) {
+                throw new InvalidArgumentException(sprintf('Parameter "calls" must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
+            }
+
             foreach ($service['calls'] as $call) {
                 $args = isset($call[1]) ? $this->resolveServices($call[1]) : array();
                 $definition->addMethodCall($call[0], $args);
@@ -212,10 +238,14 @@ class YamlFileLoader extends FileLoader
 
         if (isset($service['tags'])) {
             if (!is_array($service['tags'])) {
-                throw new InvalidArgumentException(sprintf('Parameter "tags" must be an array for service "%s" in %s.', $id, $file));
+                throw new InvalidArgumentException(sprintf('Parameter "tags" must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
             }
 
             foreach ($service['tags'] as $tag) {
+                if (!is_array($tag)) {
+                    throw new InvalidArgumentException(sprintf('A "tags" entry must be an array for service "%s" in %s. Check your YAML syntax.', $id, $file));
+                }
+
                 if (!isset($tag['name'])) {
                     throw new InvalidArgumentException(sprintf('A "tags" entry is missing a "name" key for service "%s" in %s.', $id, $file));
                 }
@@ -223,9 +253,9 @@ class YamlFileLoader extends FileLoader
                 $name = $tag['name'];
                 unset($tag['name']);
 
-                foreach ($tag as $attribute => $value) {
+                foreach ($tag as $value) {
                     if (!is_scalar($value)) {
-                        throw new InvalidArgumentException(sprintf('A "tags" attribute must be of a scalar-type for service "%s", tag "%s" in %s.', $id, $name, $file));
+                        throw new InvalidArgumentException(sprintf('A "tags" attribute must be of a scalar-type for service "%s", tag "%s" in %s. Check your YAML syntax.', $id, $name, $file));
                     }
                 }
 
@@ -279,7 +309,7 @@ class YamlFileLoader extends FileLoader
         }
 
         if (!is_array($content)) {
-            throw new InvalidArgumentException(sprintf('The service file "%s" is not valid.', $file));
+            throw new InvalidArgumentException(sprintf('The service file "%s" is not valid. It should contain an array. Check your YAML syntax.', $file));
         }
 
         foreach (array_keys($content) as $namespace) {
@@ -305,9 +335,9 @@ class YamlFileLoader extends FileLoader
     /**
      * Resolves services.
      *
-     * @param string $value
+     * @param string|array $value
      *
-     * @return Reference
+     * @return array|string|Reference
      */
     private function resolveServices($value)
     {

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/bad_calls.yml

@@ -0,0 +1,4 @@
+services:
+    method_call1:
+        class: FooClass
+        calls: foo

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/bad_import.yml

@@ -0,0 +1,2 @@
+imports:
+    - foo.yml

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/bad_imports.yml

@@ -0,0 +1,2 @@
+imports:
+    foo:bar

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/bad_parameters.yml

@@ -0,0 +1,2 @@
+parameters:
+    foo:bar

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/bad_service.yml

@@ -0,0 +1,2 @@
+services:
+    foo: bar

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/bad_services.yml

@@ -0,0 +1 @@
+services: foo

src/Symfony/Component/DependencyInjection/Tests/Fixtures/yaml/badtag4.yml

@@ -0,0 +1,6 @@
+services:
+    foo_service:
+        class:    FooClass
+        tags:
+          # tag is not an array
+          - foo

src/Symfony/Component/DependencyInjection/Tests/Loader/YamlFileLoaderTest.php

@@ -13,7 +13,6 @@ namespace Symfony\Component\DependencyInjection\Tests\Loader;
 
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Reference;
-use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\Config\Loader\Loader;
 use Symfony\Component\DependencyInjection\Loader\XmlFileLoader;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
@@ -80,6 +79,29 @@ class YamlFileLoaderTest extends \PHPUnit_Framework_TestCase
         }
     }
 
+    /**
+     * @dataProvider provideInvalidFiles
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
+     */
+    public function testLoadInvalidFile($file)
+    {
+        $loader = new YamlFileLoader(new ContainerBuilder(), new FileLocator(self::$fixturesPath.'/yaml'));
+
+        $loader->load($file.'.yml');
+    }
+
+    public function provideInvalidFiles()
+    {
+        return array(
+            array('bad_parameters'),
+            array('bad_imports'),
+            array('bad_import'),
+            array('bad_services'),
+            array('bad_service'),
+            array('bad_calls'),
+        );
+    }
+
     public function testLoadParameters()
     {
         $container = new ContainerBuilder();
@@ -179,7 +201,7 @@ class YamlFileLoaderTest extends \PHPUnit_Framework_TestCase
         $this->assertFalse($loader->supports('foo.foo'), '->supports() returns true if the resource is loadable');
     }
 
-    public function testNonArrayTagThrowsException()
+    public function testNonArrayTagsThrowsException()
     {
         $loader = new YamlFileLoader(new ContainerBuilder(), new FileLocator(self::$fixturesPath.'/yaml'));
         try {
@@ -191,6 +213,16 @@ class YamlFileLoaderTest extends \PHPUnit_Framework_TestCase
         }
     }
 
+    /**
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\InvalidArgumentException
+     * @expectedExceptionMessage A "tags" entry must be an array for service
+     */
+    public function testNonArrayTagThrowsException()
+    {
+        $loader = new YamlFileLoader(new ContainerBuilder(), new FileLocator(self::$fixturesPath.'/yaml'));
+        $loader->load('badtag4.yml');
+    }
+
     public function testTagWithoutNameThrowsException()
     {
         $loader = new YamlFileLoader(new ContainerBuilder(), new FileLocator(self::$fixturesPath.'/yaml'));