public function testMetadataExtend()
{
$reflection = new ReflectionClass();
$reflection->class = 'TestChild';
$reflection->comment = <<<'EOT'
/**
* @Groups({"group1"})
*/
EOT;
$hierarchy = new ReflectionHierarchy();
$hierarchy->addReflectionClass($reflection);
$method = new ReflectionMethod();
$method->reflectionClass = $reflection;
$method->class = 'Test';
$method->name = 'benchFoo';
$method->comment = <<<'EOT'
/**
* @Groups({"group2", "group3"}, extend=true)
*/
EOT;
$reflection->methods[$method->name] = $method;
$metadata = $this->createDriver()->getMetadataForHierarchy($hierarchy);
$subjects = $metadata->getSubjects();
$this->assertCount(1, $subjects);
$subjectOne = array_shift($subjects);
$this->assertEquals(['group1', 'group2', 'group3'], $subjectOne->getGroups());
}