Added a test case for postLoad on fetch-joined entities

see https://github.com/doctrine/doctrine2/issues/6568

tests/Doctrine/Tests/ORM/Functional/LifecycleCallbackTest.php

@@ -269,6 +269,47 @@ DQL;
         }
     }
     
+    /**
+     * https://github.com/doctrine/doctrine2/issues/6568
+     */
+    public function testPostLoadIsInvokedOnFetchJoinedEntities()
+    {
+        $entA = new LifecycleCallbackCascader();
+        $this->_em->persist($entA);
+        
+        $entB_1 = new LifecycleCallbackTestEntity();
+        $entB_2 = new LifecycleCallbackTestEntity();
+
+        $entA->entities[] = $entB_1;
+        $entA->entities[] = $entB_2;
+        $entB_1->cascader = $entA;
+        $entB_2->cascader = $entA;
+
+        $this->_em->flush();
+        $this->_em->clear();
+
+        $dql = <<<'DQL'
+SELECT
+    entA, entB
+FROM
+    Doctrine\Tests\ORM\Functional\LifecycleCallbackCascader AS entA
+LEFT JOIN
+    entA.entities AS entB
+WHERE
+    entA.id = %s
+DQL;
+
+        $fetchedA = $this
+            ->_em
+            ->createQuery(sprintf($dql, $entA->getId()))
+            ->getOneOrNullResult();
+
+        $this->assertTrue($fetchedA->postLoadCallbackInvoked);
+        foreach ($fetchedA->entities as $fetchJoinedEntB) {
+            $this->assertTrue($fetchJoinedEntB->postLoadCallbackInvoked);
+        }
+    }
+
     public function testLifecycleCallbacksGetInherited()
     {
         $childMeta = $this->_em->getClassMetadata(LifecycleCallbackChildEntity::class);