def test_revert_to_previous_state():
m = StateMachine('m')
off = State('Off')
on = State('On')
m.add_state(off, initial=True)
m.add_state(on)
m.add_transition(on, off, events=['off'])
m.add_transition(off, on, events=['on'])
m.initialize()
off.handlers = {
'test_no_history': lambda s, e: m.revert_to_previous_leaf_state()
}
assert m.leaf_state == off
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == off
assert list(m.leaf_state_stack.deque) == []
m.dispatch(_e('on'))
assert m.leaf_state == on
assert list(m.leaf_state_stack.deque) == [off]
m.dispatch(_e('off'))
assert m.leaf_state == off
assert list(m.leaf_state_stack.deque) == [off, on]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == on
assert list(m.leaf_state_stack.deque) == [off, on]
def test_revert_to_previous_state_not_reverting_after_first_iteration():
m = StateMachine('m')
one = State('One')
two = State('Two')
three = State('Three')
four = State('Four')
m.add_state(one, initial=True)
m.add_state(two)
m.add_state(three)
m.add_state(four)
m.add_transition(one, two, events=['switch_to_two'])
m.add_transition(two, three, events=['switch_to_three'])
m.add_transition(three, four, events=['switch_to_four'])
m.initialize()
for state in [one, two, three, four]:
state.handlers = {
'test_no_history': lambda s, e: m.revert_to_previous_leaf_state()
}
assert m.leaf_state == one
assert list(m.leaf_state_stack.deque) == []
m.dispatch(_e('switch_to_two'))
m.dispatch(_e('switch_to_three'))
m.dispatch(_e('switch_to_four'))
assert m.leaf_state == four
assert list(m.leaf_state_stack.deque) == [one, two, three]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == three
assert list(m.leaf_state_stack.deque) == [one, two]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == two
assert list(m.leaf_state_stack.deque) == [one]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == one
assert list(m.leaf_state_stack.deque) == []
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == one
assert list(m.leaf_state_stack.deque) == []
def test_revert_to_previous_state_not_reverting_after_first_iteration():
m = StateMachine('m')
one = State('One')
two = State('Two')
three = State('Three')
four = State('Four')
m.add_state(one, initial=True)
m.add_state(two)
m.add_state(three)
m.add_state(four)
m.add_transition(one, two, events=['switch_to_two'])
m.add_transition(two, three, events=['switch_to_three'])
m.add_transition(three, four, events=['switch_to_four'])
m.initialize()
for state in [one, two, three, four]:
state.handlers = {
'test_no_history': lambda s, e: m.revert_to_previous_leaf_state()
}
assert m.leaf_state == one
assert list(m.leaf_state_stack.deque) == []
m.dispatch(_e('switch_to_two'))
m.dispatch(_e('switch_to_three'))
m.dispatch(_e('switch_to_four'))
assert m.leaf_state == four
assert list(m.leaf_state_stack.deque) == [one, two, three]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == three
assert list(m.leaf_state_stack.deque) == [one, two]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == two
assert list(m.leaf_state_stack.deque) == [one]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == one
assert list(m.leaf_state_stack.deque) == []
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == one
assert list(m.leaf_state_stack.deque) == []
def test_revert_to_previous_state():
m = StateMachine('m')
off = State('Off')
on = State('On')
m.add_state(off, initial=True)
m.add_state(on)
m.add_transition(on, off, events=['off'])
m.add_transition(off, on, events=['on'])
m.initialize()
off.handlers = {
'test_no_history': lambda s, e: m.revert_to_previous_leaf_state()
}
assert m.leaf_state == off
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == off
assert list(m.leaf_state_stack.deque) == []
m.dispatch(_e('on'))
assert m.leaf_state == on
assert list(m.leaf_state_stack.deque) == [off]
m.dispatch(_e('off'))
assert m.leaf_state == off
assert list(m.leaf_state_stack.deque) == [off, on]
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == on
assert list(m.leaf_state_stack.deque) == [off]
# Nothing should change now as the "on" state doesn't handle the
# "test_no_history"" event.
try:
m.dispatch(_e('test_no_history'))
except Exception as exc:
assert not exc
assert m.leaf_state == on
assert list(m.leaf_state_stack.deque) == [off]