function let(EventDispatcherInterface $dispatcher, Spec $specA, Spec $specAB, Spec $specAC)
 {
     $builder = new Builder($dispatcher->getWrappedObject());
     $builder->open('A', $specA->getWrappedObject())->link('A', 'B', $specAB->getWrappedObject())->link('A', 'C', $specAC->getWrappedObject());
     $this->beConstructedThrough(array($builder, 'getWorkflow'));
 }