    def test_simple_action(self):
        '''Tests a simple action being performed upon transitioning.'''
        helper = Helper()
        states = ['one', 'two']
        transitions = [
            {'source': 'one', 'dest': 'two', 'action': helper.increment},
            {'source': 'two', 'dest': 'one'}
        ]
        sm = StateMachine(states, transitions, 'one')
        assert(helper.x == 0)
        assert(str(sm.state) == 'one')
        sm.step()
        assert(helper.x == 1)
        assert(str(sm.state) == 'two')
Tests a simple action being performed upon transitioning.
tests/state_machine_test.py