fix(events): close deferred scope after listener failure

Signed-off-by: Sebastian Krupinski <krupinski01@gmail.com>

core/lib/Event/EventDispatcher.php

@@ -60,6 +60,7 @@ final class EventDispatcher implements EventDispatcherInterface, DeferredEventPr
             throw new \LogicException('Cannot process deferred events for an inactive execution.');
         }
 
+        try {
             $processed = 0;
             $deadline = microtime(true) + 1.0;
             $deadlineExceeded = false;
@@ -78,16 +79,15 @@ final class EventDispatcher implements EventDispatcherInterface, DeferredEventPr
                 $processed += $this->invoke($event, DeliveryMode::Deferred);
             }
 
-        $remaining = count($this->deferred[$executionId]);
-        unset($this->deferred[$executionId]);
-        $this->activeExecution = null;
-
             return new DeferredProcessingResult(
                 $processed,
-            $remaining,
+                count($this->deferred[$executionId]),
                 $deadlineExceeded,
                 $limitExceeded,
             );
+        } finally {
+            $this->discardDeferred($executionId);
+        }
     }
 
     public function discardDeferred(string $executionId): void

tests/php/Unit/Event/EventDispatcherTest.php

@@ -167,6 +167,43 @@ final class EventDispatcherTest extends TestCase
         $dispatcher->dispatch(new Event('test.event'));
     }
 
+    #[Test]
+    #[TestDox('Propagated deferred failures close their execution scope')]
+    public function recoversFromDeferredFailure(): void
+    {
+        $registry = new EventListenerRegistry();
+        $registry->listen(
+            'test',
+            'test.event',
+            FailingListener::class,
+            'fail',
+            DeliveryMode::Deferred,
+            failurePolicy: FailurePolicy::Propagate,
+        );
+        $registry->freeze();
+
+        $dispatcher = new EventDispatcher(
+            $registry,
+            new RecordingContainer([FailingListener::class => new FailingListener()]),
+            new NullLogger(),
+        );
+        $dispatcher->beginExecution('failed');
+        $dispatcher->dispatch(new Event('test.event'));
+
+        try {
+            $dispatcher->processDeferred('failed');
+            self::fail('Expected deferred listener failure to propagate.');
+        } catch (\RuntimeException $error) {
+            self::assertSame('Listener failed.', $error->getMessage());
+        }
+
+        $dispatcher->beginExecution('next');
+        $result = $dispatcher->processDeferred('next');
+
+        self::assertSame(0, $result->processed);
+        self::assertSame(0, $result->remaining);
+    }
+
     #[Test]
     #[TestDox('Deferred processing stops at its configured count limit')]
     public function boundsDeferredWork(): void