[EventDispatcher] Add reference to the EventDispatcher on the Event

src/Symfony/Bundle/FrameworkBundle/Tests/ContainerAwareEventDispatcherTest.php

@@ -151,18 +151,20 @@ class ContainerAwareEventDispatcherTest extends \PHPUnit_Framework_TestCase
 
         $service = $this->getMock('Symfony\Bundle\FrameworkBundle\Tests\Service');
 
-        $service
-            ->expects($this->once())
-            ->method('onEvent')
-            ->with($event)
-        ;
-
         $container = new Container();
         $container->set('service.listener', $service);
 
         $dispatcher = new ContainerAwareEventDispatcher($container);
         $dispatcher->addListenerService('onEvent', array('service.listener', 'onEvent'));
 
+        $event->setDispatcher($dispatcher);
+
+        $service
+            ->expects($this->once())
+            ->method('onEvent')
+            ->with($event)
+        ;
+
         $this->assertTrue($dispatcher->hasListeners());
 
         if ($dispatcher->hasListeners('onEvent')) {

src/Symfony/Component/EventDispatcher/Event.php

@@ -37,6 +37,11 @@ class Event
      */
     private $propagationStopped = false;
 
+    /**
+     * @var EventDispatcher Dispatcher that dispatched this event
+     */
+    private $dispatcher;
+
     /**
      * Returns whether further event listeners should be triggered.
      *
@@ -63,4 +68,28 @@ class Event
     {
         $this->propagationStopped = true;
     }
+
+    /**
+     * Stores the EventDispatcher that dispatches this Event
+     *
+     * @param EventDispatcher $dispatcher
+     *
+     * @api
+     */
+    public function setDispatcher(EventDispatcher $dispatcher)
+    {
+        $this->dispatcher = $dispatcher;
+    }
+
+    /**
+     * Returns the EventDispatcher that dispatches this Event
+     *
+     * @return EventDispatcher
+     *
+     * @api
+     */
+    public function getDispatcher()
+    {
+        return $this->dispatcher;
+    }
 }

src/Symfony/Component/EventDispatcher/EventDispatcher.php

@@ -47,6 +47,8 @@ class EventDispatcher implements EventDispatcherInterface
             $event = new Event();
         }
 
+        $event->setDispatcher($this);
+
         $this->doDispatch($this->getListeners($eventName), $eventName, $event);
     }
 

tests/Symfony/Tests/Component/EventDispatcher/EventDispatcherTest.php

@@ -228,6 +228,16 @@ class EventDispatcherTest extends \PHPUnit_Framework_TestCase
         $this->dispatcher->removeSubscriber($eventSubscriber);
         $this->assertFalse($this->dispatcher->hasListeners(self::preFoo));
     }
+
+    public function testEventReceivesTheDispatcherInstance()
+    {
+        $test = $this;
+        $this->dispatcher->addListener('test', function ($event) use (&$dispatcher) {
+            $dispatcher = $event->getDispatcher();
+        });
+        $this->dispatcher->dispatch('test');
+        $this->assertSame($this->dispatcher, $dispatcher);
+    }
 }
 
 class TestEventListener