'If there is no known state for the destination of a handoff, then no
handoff is suggested by ``calculate_changes``.'

def test_no_handoff_if_destination_unknown(self):

    node_state = NodeState(uuid=uuid4(), hostname=u'192.2.0.1', manifestations={MANIFESTATION.dataset_id: MANIFESTATION}, devices={}, paths={})
    current = DeploymentState(nodes=[node_state])
    desired = Deployment(nodes={Node(uuid=uuid4(), manifestations={MANIFESTATION.dataset_id: MANIFESTATION})})
    api = P2PManifestationDeployer(node_state.hostname, create_volume_service(self), node_uuid=node_state.uuid)
    changes = api.calculate_changes(desired, current, NodeLocalState(node_state=node_state))
    self.assertEqual(NO_CHANGES, changes)
