'Verify that ``MountBlockDevice.run`` mounts the filesystem from the
block device for the attached volume it is given.'

def _run_test(self, mountpoint):

    scenario = _MountScenario.generate(self, mountpoint)
    self.successResultOf(scenario.create())
    change = scenario.state_change()
    return (scenario, run_state_change(change, scenario.deployer, InMemoryStatePersister()))
