"More tasks executed then were scheduled" exception thrown

[mdekrey]

First off, I'll admit to not knowing whether this is an Angular2 or Zone.js issue. Sorry if I'm putting it in the wrong Issues list!

When loading the Google Maps API asynchronously, setTimeout and clearTimeout appear to be called which causes the error More tasks executed then were scheduled.

When I load it before the zone.js library, I am able to get further in the process. However, callbacks threw similar errors (eventually) without further instrumentation. (I'm not sure if this is expected, but I suspect it is. I figured I'd mention it just in case.)

I have not been able to resolve, however, that the error occurs again if I leave the window and return upon moving my mouse over the map again. This event appears to be wholly internal to Google Maps, and I can't capture it. Unfortunately, due to the debugger; line in the code, I'm unable to just ignore it for the time being without altering the codebase.

I'm using Angular 2.0.0-beta.11 and zone.js 0.6.4.

[robwormald]

Could you post a reproduction in a plunker? This wouldn't wholly surprise me but I can't reproduce it.

[fxck]

@robwormald happens when using this lib https://github.com/stabzs/Angular2-Toaster as well, after the notification timeouts and is about to disappear

[born2net]

+1 seeing same issues
Another plunkr for reference: http://plnkr.co/edit/coyaquV0zuwwVGLGAGUE?p=preview
drag the sliders to reproduce...

[born2net]

I will add that this seems to have started in 0.10...

[born2net]

FYI disabled snippet is a workaround until issue is fixed in zone.ts

line: 763 zone.ts
if (next < 0) {
        debugger;
        throw new Error('More tasks executed then were scheduled.');
      }

[rvalimaki]

Happens with my app as well, all the time. I'm not using anything related to Google Maps, so I guess it's completely irrelevant to the subject. Probably the title should be altered to better match the subject.

@born2net: What do you mean by "disabled snippet"? I there any workaround over this issue without touching Zone.js?

I'm not sure if it's related, but I'm also receiving exceptions about Task cancellation:
"EXCEPTION: Error: Task does not support cancellation, or is already canceled.

at ZoneDelegate.cancelTask (eval at (http://localhost:8080/polyfills.bundle.js:1106:2), :218:23)
at Zone.cancelTask (eval at (http://localhost:8080/polyfills.bundle.js:1106:2), :128:44)
at eval (eval at (http://localhost:8080/polyfills.bundle.js:101:2), :88:23)
at clearTimeout (eval at createNamedFn (eval at (http://localhost:8080/polyfills.bundle.js:372:2)), :3:39)
...
"

[born2net]

yes I removed the above code from the zone file so it does not error... for now..

[DominicBoettger]

Installed angular beta9. Same issue....

[born2net]

still same issue in 0.12

More tasks executed then were scheduled.

[rvalimaki]

@DominicBoettger

did you just downgrade Angular version, or the Zone.js version too?

I'm pretty sure I didn't have any problems with our rather large application in beta.9 (apart from the obvious: minifying broken etc., but those are easy to overcome).

EDIT:
Confirmed with several times. It doesn't occur when Angular version is beta .9 and Zone.js 0.5.15, but occurs with Angular beta.11 (and reportedly 0.10 and 0.12 too) with Zone.js 0.6.4 all the time with our product.

I'm using ~latest version of Angular2-webpack-starter, and I needed to downgrade only Angular & Zone versions as well as older polyfills.ts accordingly to get rid of all errors.

EDIT2: This issue is still completely unrelated to usage of Google Maps Javascript API, as also proved by the plunker above. Though it's possible that this is somehow related to any use of an external library, such as jQuery, as is the case with above plunker and my own code.

[fxck]

no luck with b12 and 0.6.6, it's still throwing the error, the only difference is that it's not triggering debugger

[born2net]

this is a big showstopper for me...
I can't release ng 0.12 Kitchen sink: http://ng2.javascriptninja.io
due to this bug...

ng team, PLEASE remove the Throw Exceptions in zone.js

Regards,

Sean

[CaptainCodeman]

I am getting this on beta-12 - it happens when using angular2-moment, specifically the timeago pipe but not consistently. It "feels" like it's when things are rendered and removed a few times but I haven't tracked it down yet. Bizarrely, turning on source-maps to diagnose the problem seemed to make it happen less (possibly random chance or my imagination).

[ericmartinezr]

@mdekrey could you edit the title of the issue to make it easier to find please? Something like More tasks executed then were scheduled.

By the way this is being tracked here also angular/angular#7721