symfony
diff --git a/‎src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorMapping.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorMapping.php
+1-1Lines changed: 1 addition & 1 deletion b/‎src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorMapping.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Serializer/Mapping/ClassDiscriminatorMapping.php
+1-1Lines changed: 1 addition & 1 deletion
diff --git a/‎src/Symfony/Component/Serializer/Tests/Mapping/ClassDiscriminatorMappingTest.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Serializer/Tests/Mapping/ClassDiscriminatorMappingTest.php
+1Lines changed: 1 addition & 0 deletions b/‎src/Symfony/Component/Serializer/Tests/Mapping/ClassDiscriminatorMappingTest.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Serializer/Tests/Mapping/ClassDiscriminatorMappingTest.php
+1Lines changed: 1 addition & 0 deletions
@@ -53,7 +53,7 @@ public function getClassForType(string $type): ?string
     public function getMappedObjectType($object): ?string
     {
         foreach ($this->typesMapping as $type => $typeClass) {
-            if (is_a($object, $typeClass)) {
+            if (is_a($object, $typeClass, true)) {
                 return $type;
             }
         }
 
@@ -39,6 +39,7 @@ public function testMappedObjectType()
             'third' => AbstractDummyThirdChild::class,
         ]);
 
+        $this->assertEquals('first', $mapping->getMappedObjectType(AbstractDummyFirstChild::class));
         $this->assertEquals('first', $mapping->getMappedObjectType(new AbstractDummyFirstChild()));
         $this->assertNull($mapping->getMappedObjectType(new AbstractDummySecondChild()));
         $this->assertSame('third', $mapping->getMappedObjectType(new AbstractDummyThirdChild()));
Original file line number	Diff line number	Diff line change
`@@ -53,7 +53,7 @@ public function getClassForType(string $type): ?string`
`53`	`53`	`public function getMappedObjectType($object): ?string`
`54`	`54`	`{`
`55`	`55`	`foreach ($this->typesMapping as $type => $typeClass) {`
`56`		`- if (is_a($object, $typeClass)) {`
	`56`	`+ if (is_a($object, $typeClass, true)) {`
`57`	`57`	`return $type;`
`58`	`58`	`}`
`59`	`59`	`}`