Unable to access event.currentScope in $stateChangeSuccess

[ncuillery]

I searched a way to get the scope associated to the current state. I used the $stateChangeSuccess event who expose the event.currentScope... but I found a strange behavior when logging the event.currentScope :

$scope.$on('$stateChangeSuccess', function(event) {
    console.log('event ', event);
    console.log('event.currentScope', event.currentScope);
});

The first console.log displays the whole event object, and I can see what I need under the property currentScope.
But if I try to log specifically event.currentScope, I get an another scope (the $rootScope, I think).

With console.log or anything else, I can't get the currentScope.

See it in action here : http://jsfiddle.net/Cuicui74/HxrSd/11/ (open console).

[ncuillery]

I did some debugging into the $broadcast method and I think I understood the problem:

Chrome Dev Tools (and Firefox too) displays directly the Scope object in the second log (console.log(event.currentScope)) and it's the good one (the one who has his method $on used).

But with the first log (console.log(event)), it only keeps a reference and displays "Object" for the currentScope property. The value is displayed only when the user expand it by clicking on the arrow: at this time, in the $broadcast method, the "broadcast loop" is done and the currentScope property is the deepest scope in the tree, it has nothing to do with the event (or coincidentally has).

I think crazy things can happened when using a $timeout function referencing the event.currentScope for the same reason so it's a real bug. But it concerns AngularJS, not the UI-Router.

I'll make a PR.

[nateabele]

To be clear, there is no explicit support or notion of a 'current scope' when it comes to state events. There are a number of reasons for this, including the fact that a state can be attached to to any number of scopes from zero to infinity (because a state can have any number of views). Secondly, it crosses the abstraction boundary between view management and the state machine.

[ncuillery]

Thanks for explanation @nateabele.

Here is the end of the story:

I submit a PR about this problem. A correction arises from this, consisting in setting event.currentScope to null at the end of the broadcast loop. No more misleading behavior.