def test_attached_unmounted_device(self):
        dataset_id = uuid4()
        volume = self.api.create_volume(
            dataset_id=dataset_id,
            size=LOOPBACK_MINIMUM_ALLOCATABLE_SIZE,
        )
        self.api.attach_volume(
            volume.blockdevice_id,
            attach_to=self.this_node,
        )
        device_path = self.api.get_device_path(volume.blockdevice_id)
        make_filesystem(device_path, block_device=True)
        assert_discovered_state(
            self, self.deployer,
            persistent_state=PersistentState(
                blockdevice_ownership={
                    dataset_id: volume.blockdevice_id,
                }
            ),
            expected_discovered_datasets=[
                DiscoveredDataset(
                    state=DatasetStates.ATTACHED,
                    dataset_id=volume.dataset_id,
                    blockdevice_id=volume.blockdevice_id,
                    maximum_size=LOOPBACK_MINIMUM_ALLOCATABLE_SIZE,
                    device_path=device_path,
                ),
            ],
        )
If a volume is attached but not mounted, it is discovered as
dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/test/test_blockdevice.py/BlockDeviceDeployerDiscoverStateTests.test_attached_unmounted_device