bug symfony#14633 [2.3][EventDispatcher] make listeners removable from an executed listener (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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[2.3][EventDispatcher] make listeners removable from an executed listener

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | symfony#13972
| License       | MIT
| Doc PR        |

This fixes symfony#13972 for Symfony 2.3. On Symfony 2.6 and higher, this has already been fixed with symfony#14355.

Commits
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54bb399 [EventDispatcher] make listeners removable from an executed listener

Author: fabpot

src/Symfony/Component/HttpKernel/Debug/TraceableEventDispatcher.php

@@ -88,6 +88,18 @@ public function addSubscriber(EventSubscriberInterface $subscriber)
      */
     public function removeListener($eventName, $listener)
     {
+        if (isset($this->wrappedListeners[$this->lastEventId])) {
+            foreach ($this->wrappedListeners[$this->lastEventId] as $wrappedListener) {
+                $originalListener = $this->wrappedListeners[$this->lastEventId][$wrappedListener];
+
+                if ($originalListener === $listener) {
+                    unset($this->wrappedListeners[$this->lastEventId][$wrappedListener]);
+
+                    return $this->dispatcher->removeListener($eventName, $wrappedListener);
+                }
+            }
+        }
+
         return $this->dispatcher->removeListener($eventName, $listener);
     }
 

src/Symfony/Component/HttpKernel/Tests/Debug/TraceableEventDispatcherTest.php

@@ -223,6 +223,19 @@ public function testStopwatchStopControllerOnRequestEvent()
         $kernel->handle($request);
     }
 
+    public function testListenerCanRemoveItselfWhenExecuted()
+    {
+        $eventDispatcher = new TraceableEventDispatcher(new EventDispatcher(), new Stopwatch());
+        $listener1 = function () use ($eventDispatcher, &$listener1) {
+            $eventDispatcher->removeListener('foo', $listener1);
+        };
+        $eventDispatcher->addListener('foo', $listener1);
+        $eventDispatcher->addListener('foo', function () {});
+        $eventDispatcher->dispatch('foo');
+
+        $this->assertCount(1, $eventDispatcher->getListeners('foo'), 'expected listener1 to be removed');
+    }
+
     protected function getHttpKernel($dispatcher, $controller)
     {
         $resolver = $this->getMock('Symfony\Component\HttpKernel\Controller\ControllerResolverInterface');