def test_create_result(self):
        reactor = FakeProcessReactor()
        snapshots = ZFSSnapshots(reactor, Filesystem(b"mypool", None))
        d = snapshots.create(b"name")
        reactor.processes[0].processProtocol.processEnded(
            Failure(ProcessDone(0)))
        self.assertEqual(self.successResultOf(d), None)
The result of ``ZFSSnapshots.create()`` is a ``Deferred`` that fires
dataset/ETHPy150Open ClusterHQ/flocker/flocker/volume/test/test_filesystems_zfs.py/ZFSSnapshotsTests.test_create_result