'If the same change is passed to ``in_parallel`` twice then it is run
twice.'

def test_duplicates_run(self):

    deployer = DummyDeployer()
    the_change = RunSpyStateChange(value=0)
    parallel = in_parallel(changes=[the_change, the_change])
    self.successResultOf(parallel.run(deployer, state_persister=InMemoryStatePersister()))
    self.assertEqual(2, the_change.value)
