Test MetaData merge with parent annotation.
public function testLoadParentClassMetadata() {
$loader = new AnnotationLoader(new AnnotationReader());
// Load Parent MetaData
$parent_metadata = new ClassMetadata('Symfony\\Component\\Validator\\Tests\\Fixtures\\EntityParent');
$loader
->loadClassMetadata($parent_metadata);
$expected_parent = new ClassMetadata('Symfony\\Component\\Validator\\Tests\\Fixtures\\EntityParent');
$expected_parent
->addPropertyConstraint('other', new NotNull());
$expected_parent
->getReflectionClass();
$this
->assertEquals($expected_parent, $parent_metadata);
}