def test_after(self):
     t = Transition('a', ['b'], after=self.sample_hook(4))
     assert t.after() == 4
     assert t.before() == None
 def test_both_hooks(self):
     t = Transition('a', ['b'],
                    before=self.sample_hook(4),
                    after=self.sample_hook(5))
     assert t.before() == 4
     assert t.after() == 5
 def test_empty_hooks(self):
     t = Transition('a', ['b'])
     assert t.before() == None
     assert t.after() == None