[DI] Add compiler pass which check extistence of service class and

factory_class name (using class_exists() ) if that is possible - definition is not syntetic or is
not definition via factory method.

src/Symfony/Bundle/FrameworkBundle/Tests/Controller/ControllerResolverTest.php

@@ -109,8 +109,8 @@ public function testGetControllerOnNonUndefinedFunction($controller, $exceptionN
     public function getUndefinedControllers()
     {
         return array(
-            array('foo', '\LogicException', 'Unable to parse the controller name "foo".'),
-            array('foo::bar', '\InvalidArgumentException', 'Class "foo" does not exist.'),
+            array('myfoo', '\LogicException', 'Unable to parse the controller name "myfoo".'),
+            array('myfoo::bar', '\InvalidArgumentException', 'Class "myfoo" does not exist.'),
             array('stdClass', '\LogicException', 'Unable to parse the controller name "stdClass".'),
             array(
                 'Symfony\Component\HttpKernel\Tests\Controller\ControllerResolverTest::bar',

src/Symfony/Component/DependencyInjection/Compiler/CheckServiceClassPass.php

@@ -0,0 +1,57 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Compiler;
+
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+use Symfony\Component\DependencyInjection\Definition;
+use Symfony\Component\DependencyInjection\Exception\BadServiceClassException;
+
+/**
+ * Checks your service exists by checking its definition "class" and "factory_class" keys
+ *
+ * @author Leszek "l3l0" Prabucki <leszek.prabucki@gmail.com>
+ */
+class CheckServiceClassPass implements CompilerPassInterface
+{
+    /**
+     * Checks if ContainerBuilder services exists
+     *
+     * @param ContainerBuilder $container The ContainerBuilder instances
+     */
+    public function process(ContainerBuilder $container)
+    {
+        $parameterBag = $container->getParameterBag();
+        foreach ($container->getDefinitions() as $id => $definition) {
+            if ($this->allowsToCheckClassExistenceForClass($definition) && !class_exists($parameterBag->resolveValue($definition->getClass()))) {
+                throw new BadServiceClassException($id, $definition->getClass(), 'class');
+            }
+            if ($this->allowsToCheckClassExistenceForFactoryClass($definition) && !class_exists($parameterBag->resolveValue($definition->getFactoryClass()))) {
+                throw new BadServiceClassException($id, $definition->getFactoryClass(), 'factory_class');
+            }
+        }
+    }
+
+    private function allowsToCheckClassExistenceForClass(Definition $definition)
+    {
+        return $definition->getClass() && !$this->isFactoryDefinition($definition) && !$definition->isSynthetic();
+    }
+
+    private function allowsToCheckClassExistenceForFactoryClass(Definition $definition)
+    {
+        return $definition->getFactoryClass() && !$definition->isSynthetic();
+    }
+
+    private function isFactoryDefinition(Definition $definition)
+    {
+       return $definition->getFactoryClass() || $definition->getFactoryService();
+    }
+}

src/Symfony/Component/DependencyInjection/Compiler/PassConfig.php

@@ -67,6 +67,7 @@ public function __construct()
                 new RemoveUnusedDefinitionsPass(),
             )),
             new CheckExceptionOnInvalidReferenceBehaviorPass(),
+            new CheckServiceClassPass(),
         );
     }
 

src/Symfony/Component/DependencyInjection/Exception/BadServiceClassException.php

@@ -0,0 +1,27 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Exception;
+
+class BadServiceClassException extends RuntimeException
+{
+    public function __construct($id, $className, $key)
+    {
+        parent::__construct(
+            sprintf(
+                'Class "%s" not found. Check the spelling on the "%s" configuration for your "%s" service.',
+                $className,
+                $key,
+                $id
+            )
+        );
+    }
+}

src/Symfony/Component/DependencyInjection/Tests/Compiler/CheckServiceClassPassTest.php

@@ -0,0 +1,106 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\DependencyInjection\Tests\Compiler;
+
+use Symfony\Component\DependencyInjection\Compiler\CheckServiceClassPass;
+use Symfony\Component\DependencyInjection\ContainerBuilder;
+
+class CheckServiceClassPassTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\BadServiceClassException
+     * @expectedExceptionMessage Class "\InvalidName\TestClass" not found. Check the spelling on the "class" configuration for your "a" service.
+     */
+    public function testThrowsBadNameExceptionWhenServiceHasInvalidClassName()
+    {
+        $container = new ContainerBuilder();
+        $container->register('a', '\InvalidName\TestClass');
+
+        $this->process($container);
+    }
+
+    public function testDoesNotThrowExceptionIfClassExists()
+    {
+        $container = new ContainerBuilder();
+        $container->register('a', '\Symfony\Component\DependencyInjection\Compiler\CheckServiceClassPass');
+        $container->register('b', '\stdClass');
+        $container->register('c', '\Symfony\Component\DependencyInjection\Tests\Compiler\MyTestService');
+        $container
+            ->register('d', '\stdClass')
+            ->setFactoryService('\Symfony\Component\DependencyInjection\Tests\Compiler\MyTestService')
+            ->setFactoryMethod('factoryMethod')
+        ;
+
+        $this->process($container);
+    }
+
+    public function testSynteticServicesClassNamesAreNotChecked()
+    {
+        $container = new ContainerBuilder();
+        $container
+            ->register('a', '\InvalidName\TestClass')
+            ->setSynthetic(true)
+        ;
+
+        $this->process($container);
+    }
+
+    /**
+     * @expectedException \Symfony\Component\DependencyInjection\Exception\BadServiceClassException
+     * @expectedExceptionMessage Class "\InvalidName\TestClass" not found. Check the spelling on the "factory_class" configuration for your "a" service.
+     */
+    public function testFactoryMethodServicesClassNamesAreNotChecked()
+    {
+        $container = new ContainerBuilder();
+        $container
+            ->register('a', '\stdClass')
+            ->setFactoryClass('\InvalidName\TestClass')
+            ->setFactoryMethod('factoryMethod')
+        ;
+
+        $this->process($container);
+    }
+
+    public function testServicesWithoutNameAreNotChecked()
+    {
+        $container = new ContainerBuilder();
+        $container
+            ->register('a')
+        ;
+
+        $this->process($container);
+    }
+
+    public function testSynteticServicesNameAreNotChecked()
+    {
+        $container = new ContainerBuilder();
+        $container
+            ->register('a', '\InvalidName\TestClass')
+            ->setSynthetic(true)
+        ;
+
+        $this->process($container);
+    }
+
+    protected function process(ContainerBuilder $container)
+    {
+        $pass = new CheckServiceClassPass();
+        $pass->process($container);
+    }
+}
+
+class MyTestService
+{
+    public function factoryMethod()
+    {
+    }
+}

src/Symfony/Component/DependencyInjection/Tests/Compiler/IntegrationTest.php

@@ -111,4 +111,20 @@ public function testProcessInlinesWhenThereAreMultipleReferencesButFromTheSameDe
         $this->assertFalse($container->hasDefinition('b'));
         $this->assertFalse($container->hasDefinition('c'), 'Service C was not inlined.');
     }
+
+    /**
+     * @expectedException        \Symfony\Component\DependencyInjection\Exception\BadServiceClassException
+     * @expectedExceptionMessage Class "\NotExist\InvalidClass" not found. Check the spelling on the "class" configuration for your "a" service.
+     */
+    public function testFriendlyErrorIsThrowedWhenServiceHasBadClassName()
+    {
+        $container = new ContainerBuilder();
+
+        $container
+            ->register('a', '\NotExist\InvalidClass')
+        ;
+
+        $container->compile();
+    }
+
 }

src/Symfony/Component/DependencyInjection/Tests/Fixtures/containers/container9.php

@@ -1,6 +1,7 @@
 <?php
 
 require_once __DIR__.'/../includes/classes.php';
+require_once __DIR__.'/../includes/foo.php';
 
 use Symfony\Component\DependencyInjection\ContainerInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;

src/Symfony/Component/DependencyInjection/Tests/Fixtures/includes/ProjectExtension.php

@@ -4,6 +4,19 @@
 use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\DependencyInjection\Extension\ExtensionInterface;
 
+//Services have to exist
+class FooClass
+{
+}
+
+class BAR
+{
+}
+
+class Foo
+{
+}
+
 class ProjectExtension implements ExtensionInterface
 {
     public function load(array $configs, ContainerBuilder $configuration)

src/Symfony/Component/DependencyInjection/Tests/Fixtures/includes/classes.php

@@ -59,3 +59,15 @@ public function __construct(BarClass $bar)
         $this->bar = $bar;
     }
 }
+
+class Baz
+{
+}
+
+class Request
+{
+}
+
+class ConfClass
+{
+}