bug symfony#61291 [Messenger] Remove fix NoAutoAckStamp handling in Worker::flush() (wazum)

This PR was merged into the 6.4 branch.

Discussion
----------

[Messenger] Remove fix `NoAutoAckStamp` handling in `Worker::flush()`

| Q             | A
| ------------- | ---
| Branch?       | 6.4
| Bug fix?      | yes
| New feature?  | no
| Deprecations? | no
| Issues        | -
| License       | MIT

## Description

This PR removes unused code in the `Worker::flush()` method where an envelope modification was never used.

## Changes

- Removed the line `$envelope = $envelope->withoutAll(NoAutoAckStamp::class);` which was modifying a local variable that was immediately discarded
- Moved the `NoAutoAckStamp` removal to the catch block where it's actually needed

## Why this change?

The line was unused code because:
1. If `dispatch()` succeeds: The modified envelope is never used (foreach continues/ends)
2. If `dispatch()` throws: The line is never reached

Moving the stamp removal to the `catch` block ensures that envelopes stored for acknowledgment have clean state - they shouldn't contain a "no auto ack" stamp when they're about to be acknowledged.

Commits
-------

06b1d8f [Messenger] Fix NoAutoAckStamp handling in Worker::flush()

Author: nicolas-grekas

src/Symfony/Component/Messenger/Tests/Fixtures/DummyReceiver.php

@@ -63,4 +63,9 @@ public function getAcknowledgedEnvelopes(): array
     {
         return $this->acknowledgedEnvelopes;
     }
+
+    public function getRejectedEnvelopes(): array
+    {
+        return $this->rejectedEnvelopes;
+    }
 }

src/Symfony/Component/Messenger/Tests/WorkerTest.php

@@ -38,6 +38,8 @@
 use Symfony\Component\Messenger\MessageBusInterface;
 use Symfony\Component\Messenger\Middleware\HandleMessageMiddleware;
 use Symfony\Component\Messenger\Stamp\ConsumedByWorkerStamp;
+use Symfony\Component\Messenger\Stamp\FlushBatchHandlersStamp;
+use Symfony\Component\Messenger\Stamp\NoAutoAckStamp;
 use Symfony\Component\Messenger\Stamp\ReceivedStamp;
 use Symfony\Component\Messenger\Stamp\SentStamp;
 use Symfony\Component\Messenger\Stamp\StampInterface;
@@ -584,6 +586,49 @@ public function testFlushBatchOnStop()
 
         $this->assertSame($expectedMessages, $handler->processedMessages);
     }
+
+    public function testFlushRemovesNoAutoAckStampOnException()
+    {
+        $envelope = new Envelope(new DummyMessage('Test'));
+        $receiver = new DummyReceiver([[$envelope]]);
+
+        $bus = new class implements MessageBusInterface {
+            public function dispatch(object $message, array $stamps = []): Envelope
+            {
+                $envelope = Envelope::wrap($message, $stamps);
+                if ($envelope->last(FlushBatchHandlersStamp::class)) {
+                    throw new \RuntimeException('Flush failed');
+                }
+
+                return $envelope;
+            }
+        };
+
+        $dispatcher = new EventDispatcher();
+        $dispatcher->addListener(WorkerRunningEvent::class, function (WorkerRunningEvent $event) {
+            static $calls = 0;
+            if (++$calls >= 2) {
+                $event->getWorker()->stop();
+            }
+        });
+
+        $worker = new Worker(['transport' => $receiver], $bus, $dispatcher, clock: new MockClock());
+
+        $reflection = new \ReflectionClass($worker);
+        $unacksProperty = $reflection->getProperty('unacks');
+        $unacks = $unacksProperty->getValue($worker);
+        $dummyHandler = new DummyBatchHandler();
+        $envelopeWithNoAutoAck = $envelope->with(new NoAutoAckStamp(new HandlerDescriptor($dummyHandler)));
+        $unacks->attach($dummyHandler, [$envelopeWithNoAutoAck, 'transport']);
+
+        $worker->run();
+
+        $this->assertSame(1, $receiver->getRejectCount());
+        $rejectedEnvelopes = $receiver->getRejectedEnvelopes();
+        $this->assertCount(1, $rejectedEnvelopes);
+        $rejectedEnvelope = $rejectedEnvelopes[0];
+        $this->assertNull($rejectedEnvelope->last(NoAutoAckStamp::class));
+    }
 }
 
 class DummyQueueReceiver extends DummyReceiver implements QueueReceiverInterface

src/Symfony/Component/Messenger/Worker.php

@@ -257,9 +257,9 @@ private function flush(bool $force): bool
             [$envelope, $transportName] = $unacks[$batchHandler];
             try {
                 $this->bus->dispatch($envelope->with(new FlushBatchHandlersStamp($force)));
-                $envelope = $envelope->withoutAll(NoAutoAckStamp::class);
                 unset($unacks[$batchHandler], $batchHandler);
             } catch (\Throwable $e) {
+                $envelope = $envelope->withoutAll(NoAutoAckStamp::class);
                 $this->acks[] = [$transportName, $envelope, $e];
             }
         }