stewx

export function setFakeTimer(maxFrames?: number): TestScheduler {
  const originalTimer = Observable.timer;
  const scheduler = new TestScheduler((a, b) => expect(a).toEqual(b));
  if (maxFrames) {
    scheduler.maxFrames = maxFrames;
  }
  spyOn(Observable, 'timer').and.callFake((initialDelay: number, dueTime: number) => {
    return originalTimer.call(this, initialDelay, dueTime, scheduler);
  });