Failing test case: TraceableMessageBus crashes when computing backtrace of array_map() call

Ocramius · Ocramius · commit a894125625b3 · 2021-10-27T15:28:33.000+02:00
This test shows that `array_map([new TraceableMessageBus(...), 'dispatch'], $messages)` does not work at all,
because `debug_backtrace()` is used in internals to compute the call-site, and it is not considering the fact
that the caller may be:

 * an internal PHP function
 * a callback (this example test scenario)
 * generated code (`eval()` result)

The output of such a failure:

```
1) Symfony\Component\Messenger\Tests\TraceableMessageBusTest::testItTracesExceptionsWhenMessageBusIsFiredFromArrayCallback
Undefined array key "line"

/app/src/Symfony/Component/Messenger/TraceableMessageBus.php:66
/app/src/Symfony/Component/Messenger/TraceableMessageBus.php:36
/app/src/Symfony/Component/Messenger/Tests/TraceableMessageBusTest.php:175
```
diff --git a/src/Symfony/Component/Messenger/Tests/TraceableMessageBusTest.php b/src/Symfony/Component/Messenger/Tests/TraceableMessageBusTest.php
@@ -156,4 +156,22 @@ public function testItTracesExceptions()
             ],
         ], $actualTracedMessage);
     }
+
+    public function testItTracesExceptionsWhenMessageBusIsFiredFromArrayCallback(): void
+    {
+        $message = new DummyMessage('Hello');
+        $exception = new \RuntimeException();
+
+        $bus = $this->createMock(MessageBusInterface::class);
+        $bus->expects($this->once())
+            ->method('dispatch')
+            ->with($message)
+            ->willThrowException($exception);
+
+        $traceableBus = new TraceableMessageBus($bus);
+
+        $this->expectExceptionObject($exception);
+
+        array_map([$traceableBus, 'dispatch'], [$message]);
+    }
 }
