'An update that is ignorant about certain parts of a node\'s state only
updates the information it knows about.'

def test_partial_update(self):

    service = self.service()
    service.apply_changes([NodeState(hostname=u'host1', applications={APP1.name: APP1}), NodeState(hostname=u'host1', applications=None, manifestations={MANIFESTATION.dataset_id: MANIFESTATION}, devices={}, paths={})])
    self.assertEqual(service.as_deployment(), DeploymentState(nodes=[NodeState(hostname=u'host1', manifestations={MANIFESTATION.dataset_id: MANIFESTATION}, devices={}, paths={}, applications={APP1.name: APP1})]))
