A question about from "outside-to-child-transition"

[Alexey Morozov]

Hi!

I got another question which is likely caused by my misunderstanding what is possible to do with hierarchical SMs and what is not. Is it legal to jump directly from a  particular state to another state's child? Should the call sequence be "straightforward" in this case or maybe some extra steps are expected?

I have prepared a test case which demonstrates my troubles regarding this question

Suppose we have the following state machine description:

public class HierarchicalStateMachineTest {

    public enum HState {
        A, D, E, E1
    }
    public enum HEvent {
        A2D, D2E1
    }

    @States({
        @State(name="A", initialState=true),
        @State(name="D", entryCallMethod="enterD", exitCallMethod="leftD"),
        @State(name="E", entryCallMethod="enterE", exitCallMethod="leftE"),
        @State(parent="E", name="E1", entryCallMethod="enterE1", exitCallMethod="leftE1"),
        })
    @Transitions({
        @Transit(from="A", to="D", on="A2D", callMethod="transitA2D"),
        @Transit(from="D", to="E1", on="D2E1", callMethod="transitD2E1"),
        @Transit(from="A", to="C", on="Finish", callMethod="transitA2C"),
        })
    static class HierachicalStateMachine extends AbstractStateMachine<HierachicalStateMachine, HState, HEvent, Integer> {
        ... methods definitions as in HierarchicalStateMachineTest from the Squirrel Test Suite
    }

    @Test
    public void testChildTransition() {
      stateMachine.start();
      stateMachine.consumeLog();
      stateMachine.fire(HEvent.A2D, 1);
      stateMachine.consumeLog();
      stateMachine.fire(HEvent.D2E1, 2);
      assertThat(stateMachine.consumeLog(), is(equalTo("leftD.transitD2E1.enterE.enterE1")));
      assertThat(stateMachine.getCurrentState(), is(equalTo(HState.E1)));
    }

The test fails. The actual call sequence in this case happens to be the following: "leftD.enterD.leftD.transitD2E1.enterE.enterE1". As one may see, one extra `enterD` and `leftD` happen, quite unexpectedly for me. I'm still not sure if this is a problem of the test (that is somewhere in the state machine definition) or the problem in the state machine processor.

I've have attached the complete test as a patch to the HierarchicalStateMachineTest.java from current master.

Thanks,
Alexey

[Alexey Morozov]

What's more intriguing is that introduction of an otherwise unneeded child state D1 and jumping from D1 to E1 solves the problem completely. The resulting sequence is 'leftD1.leftD.transitD12E1.enterE.enterE1'.

[He Henry]

Hi,

I think your expectation is correct. It is probably a bug. I will fixed later.

Thanks,

Henry

在 2014年7月29日星期二UTC+8上午7时48分17秒，Alexey Morozov写道：

[He Henry]

Fixed in latest snapshot version.

[Alexey Morozov]

Thank you so much!

31.07.2014 17:19, He Henry writes:
> Fixed in latest snapshot version.
>