console warning: cycle-plugin.js:49 Cyclic next detected

Worrying console message

cycle-plugin.js:49 Cyclic next detected; type = subject; value = Scroll(anchor: 'null', position: 'null'); subscribed at
RouterScroller.push../node_modules/@angular/router/fesm5/router.js.RouterScroller.createScrollEvents()@http://localhost:5009/vendor.js:73846:35
RouterScroller.push../node_modules/@angular/router/fesm5/router.js.RouterScroller.init()@http://localhost:5009/vendor.js:73841:46
RouterInitializer.push../node_modules/@angular/router/fesm5/router.js.RouterInitializer.bootstrapListener()@http://localhost:5009/vendor.js:74223:24
{anonymous}()@http://localhost:5009/vendor.js:43425:56

Evidently something going on in Angular router. Not asking you to fix it.

I am asking what the warning is telling me and what someone (the Angular team?) should do about it.

Trying this promising library for the first time with angular@^6.1.9 and rxjs@^6.3.3

[bschantz]

@msorens The console environment won’t have any knowledge of CyclePlugin – it needs to be in code:

import { create } from 'rxjs-spy';
import { CyclePlugin } from 'rxjs-spy/plugin';
const spy = create();
spy.unplug(spy.find(CyclePlugin));

[cartant]

Could you may deploy a new version of rxjs-spy so that we can consume it with npm.

No. I’m not inclined to do that. Soon, I’m going to release rxjs-devtools. It will have some new features and will replace rxjs-spy. The changes you mention were reverted and the work I was doing was moved to a new repo - which will also include a Chrome DevTools extension.

Could you explain it easier?

Not really. It means there is a feedback loop. That is, when a source observable emits, something happens in a listener that effects another synchronous emission from the source observable.