[Testing with readFirst] Observable type error on nx version 15.0.6 and above

Hi,

I have an angular application and am currently on nx version 15.0.5 with rxjs version 7.5.6 and have the problem that the unit test fail when I update to all the newer patch versions.

Current Behavior

The unit test fail on the readFirst, as it seems that the Observable import is not the same as the Observable import of rxjs, which confuses me. The exact error:

Argument of type ‘import(“/…/node_modules/rxjs/dist/types/internal/Observable”).Observable<boolean>’ is not assignable to parameter of type ‘import(“/…/node_modules/@nrwl/angular/node_modules/rxjs/internal/Observable”).Observable<boolean>’.

Type ‘Observable<boolean>’ is missing the following properties from type ‘Observable<boolean>’: _isScalar, _trySubscribe, _subscribe

Expected Behavior

No type error, unit test succeeds just like in nx version 15.0.5.

Steps to Reproduce

Use readFirst for a unit test in nx version 15.0.6 or above.

[sjimenez77]

Yes, you are right @Coly010! I forgot completely the firstValueFrom operator 😄. I think that I will replace it everywhere.

[Coly010]

You might be able to use the firstValueFrom operator from RxJS itself https://rxjs.dev/api/index/function/firstValueFrom