'If no devices exist and no datasets are part of the configuration for
the deployer\'s node, no state changes are calculated.'

def test_no_devices_no_local_datasets(self):

    dataset_id = unicode(uuid4())
    manifestation = Manifestation(dataset=Dataset(dataset_id=dataset_id), primary=True)
    node = u'192.0.2.1'
    node_uuid = uuid4()
    other_node = u'192.0.2.2'
    other_node_uuid = uuid4()
    configuration = Deployment(nodes={Node(hostname=other_node, uuid=other_node_uuid, manifestations={dataset_id: manifestation})})
    state = DeploymentState(nodes=[])
    deployer = create_blockdevicedeployer(self, hostname=node, node_uuid=node_uuid)
    local_state = local_state_from_shared_state(node_state=state.get_node(node_uuid, hostname=node), nonmanifest_datasets={})
    changes = deployer.calculate_changes(configuration, state, local_state)
    self.assertEqual(in_parallel(changes=[]), changes)
