'A ``zfs`` subprocess is launched with the given arguments.'

def test_call(self):

    reactor = FakeProcessReactor()
    zfs_command(reactor, ['-H', 'lalala'])
    arguments = reactor.processes[0]
    self.assertEqual((arguments.executable, arguments.args, arguments.env), ('zfs', ['zfs', '-H', 'lalala'], os.environ))
