@expectedException \Symfony\Component\Validator\Exception\NoSuchMetadataException
public function testMetadataMustExistIfTraversalIsDisabled() {
$entity = new Entity();
$entity->reference = new \ArrayIterator();
$this->metadata
->addPropertyConstraint('reference', new Valid(array(
'traverse' => false,
)));
$this->visitor
->validate($entity, 'Default', '');
}