Testing and mocking lettable operators in RxJS 5.5

Question

Before lettable operator, I did a helper to modify debounceTime method, so it uses a TestScheduler:

export function mockDebounceTime(
    scheduler: TestSche         


        

Answer 1

You can use the second argument that accepts a custom Scheduler.

  debounceTime(DEFAULT_DEBOUNCE_TIME, rxTestScheduler),

All code

import { Scheduler } from 'rxjs/scheduler/Scheduler';
import { asap } from 'rxjs/scheduler/asap';

@Injectable()
export class EffectsService {
  constructor(private scheduler: Scheduler = asap) { }

  @Effect()
  public filterUpdated$ = this.actions$
    .ofType(UPDATE_FILTERS)
    .pipe(
        debounceTime(DEFAULT_DEBOUNCE_TIME, this.scheduler),
        mergeMap(action => [...])
    );
}

Then on test

describe('Service: EffectsService', () => {
  //setup
  beforeEach(() => TestBed.configureTestingModule({
    EffectsService, 
    { provide: Scheduler, useValue: rxTestScheduler} ]
  }));

  //specs
  it('should update filters using debounce', inject([EffectsService], service => {
    // your test
  });
});