'``NonManifestDatasets.update_cluster_state`` returns a new
``DeploymentState`` instance with its ``nonmanifest_datasets`` field
replaced with the value of the ``NonManifestDatasets.datasets`` field.'

def test_update_cluster_state(self):

    dataset = Dataset(dataset_id=unicode(uuid4()))
    datasets = {dataset.dataset_id: dataset}
    nonmanifest = NonManifestDatasets(datasets=datasets)
    deployment = DeploymentState()
    updated = nonmanifest.update_cluster_state(deployment)
    self.assertEqual(datasets, thaw(updated.nonmanifest_datasets))
