def test_no_volumes(self):
        raw_state = self.deployer._discover_raw_state()
        self.assertEqual(raw_state.volumes, [])
``BlockDeviceDeployer._discover_raw_state`` returns a
dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/test/test_blockdevice.py/BlockDeviceDeployerDiscoverRawStateTests.test_no_volumes