nxtep-io/nano-fsm

Minimalistic finite state machine for Typescript / Javascript environments.

nano-fsm's Issues

Transition should fail if beforeTransition or afterTransition return false

Only the return value of onTransition is considered on a transition change - if beforeTransition or afterTransition return false, the transition will still work as expected.

Also, if beforeTransition throws it works as expected because the error bubbles up and goTo throws before calling setTo.
But if afterTransition throws, goTo still throws, but setTo is called and the state is changed.

BUG: Winston 3 Logger

Winston 3 no longer accepts using new Logger() and this always throws an error when you try to initialize a StateMachine without passing the logger:
Simple logger constructor is deprecated in Winston 3, use Logger.initialize() instead (stackId: bb8e6b70-5ffc-488e-ad17-607805315b87)

Get back to 100% test coverage

There are currently two ternary operators not fully covered by the test suit, as all test cases follow the same branch of it.

Feature Request: Throw error if action is registered with non-registered status

Moving to same state will only call afterTransition lifecycle

An state change to the same state is defined here:

nano-fsm/lib/FiniteStateMachine.ts

Lines 143 to 148 in 371c0f7

	if (to === state && !this.options.allowSameState) {
	throw new Error(`Machine is already in "${state}" state`);
	} else if (to === state) {
	await this.setState(state, to, []);
	return true;
	}

And the afterTransition lifecycle is called by setState

nano-fsm/lib/FiniteStateMachine.ts

Lines 121 to 132 in 371c0f7

	protected async setState(
	from: State | (State | string)[],
	to: State,
	actions: Action<Instance, State>[]
	): Promise<void> {
	// Set the next state locally
	this._state = to;
	// Notify we're entered the next state
	await Promise.all(actions.map(action => action.afterTransition(this.instance)));
	await this.afterTransition(from, to);
	}

But no other lifecycles are called on this case.