[Messenger] Add method HandlerFailedException::getNestedExceptionOfClass

To know if specific exception are the origin of messenger failure

src/Symfony/Component/Messenger/Exception/HandlerFailedException.php

@@ -49,4 +49,16 @@ class HandlerFailedException extends RuntimeException
     {
         return $this->exceptions;
     }
+
+    public function getNestedExceptionOfClass(string $exceptionClassName): array
+    {
+        return array_values(
+            array_filter(
+                $this->exceptions,
+                function ($exception) use ($exceptionClassName) {
+                    return is_a($exception, $exceptionClassName);
+                }
+            )
+        );
+    }
 }

src/Symfony/Component/Messenger/Tests/Exception/HandlerFailedExceptionTest.php

@@ -5,6 +5,8 @@ namespace Symfony\Component\Messenger\Tests\Exception;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Messenger\Envelope;
 use Symfony\Component\Messenger\Exception\HandlerFailedException;
+use Symfony\Component\Messenger\Tests\Fixtures\MyOwnChildException;
+use Symfony\Component\Messenger\Tests\Fixtures\MyOwnException;
 
 class HandlerFailedExceptionTest extends TestCase
 {
@@ -28,4 +30,31 @@ class HandlerFailedExceptionTest extends TestCase
         $this->assertIsString($originalException->getCode(), 'Original exception code still with original type (string)');
         $this->assertSame($exception->getCode(), $originalException->getCode(), 'Original exception code is not modified');
     }
+
+    public function testThatNestedExceptionClassAreFound()
+    {
+        $envelope = new Envelope(new \stdClass());
+        $exception = new MyOwnException();
+
+        $handlerException = new HandlerFailedException($envelope, [new \LogicException(), $exception]);
+        $this->assertSame([$exception], $handlerException->getNestedExceptionOfClass(MyOwnException::class));
+    }
+
+    public function testThatNestedExceptionClassAreFoundWhenUsingChildException()
+    {
+        $envelope = new Envelope(new \stdClass());
+        $exception = new MyOwnChildException();
+
+        $handlerException = new HandlerFailedException($envelope, [$exception]);
+        $this->assertSame([$exception], $handlerException->getNestedExceptionOfClass(MyOwnException::class));
+    }
+
+    public function testThatNestedExceptionClassAreNotFoundIfNotPresent()
+    {
+        $envelope = new Envelope(new \stdClass());
+        $exception = new \LogicException();
+
+        $handlerException = new HandlerFailedException($envelope, [$exception]);
+        $this->assertCount(0, $handlerException->getNestedExceptionOfClass(MyOwnException::class));
+    }
 }

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

@@ -0,0 +1,16 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Messenger\Tests\Fixtures;
+
+class MyOwnChildException extends MyOwnException
+{
+}

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

@@ -0,0 +1,16 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Messenger\Tests\Fixtures;
+
+class MyOwnException extends \Exception
+{
+}