Merge pull request #50 from qmuntal/dynerr

Return error from PermitDynamic

statemachine.go

@@ -381,10 +381,9 @@ func (sm *StateMachine) internalFireOne(ctx context.Context, trigger Trigger, ar
 		transition := Transition{Source: source, Destination: t.Destination, Trigger: trigger}
 		err = sm.handleReentryTrigger(ctx, representativeState, transition, args...)
 	case *dynamicTriggerBehaviour:
-		destination, ok := t.ResultsInTransitionFrom(ctx, source, args...)
-		if !ok {
-			err = fmt.Errorf("stateless: Dynamic handler for trigger %v in state %v has failed", trigger, source)
-		} else {
+		var destination interface{}
+		destination, err = t.Destination(ctx, args...)
+		if err == nil {
 			transition := Transition{Source: source, Destination: destination, Trigger: trigger}
 			err = sm.handleTransitioningTrigger(ctx, representativeState, transition, args...)
 		}

triggers.go

@@ -113,15 +113,6 @@ type dynamicTriggerBehaviour struct {
 	Destination func(context.Context, ...interface{}) (State, error)
 }
 
-func (t *dynamicTriggerBehaviour) ResultsInTransitionFrom(ctx context.Context, _ State, args ...interface{}) (st State, ok bool) {
-	var err error
-	st, err = t.Destination(ctx, args...)
-	if err == nil {
-		ok = true
-	}
-	return
-}
-
 type internalTriggerBehaviour struct {
 	baseTriggerBehaviour
 	Action ActionFunc