describe('use jasmine.clock()', () => {
  // need to config __zone_symbol__fakeAsyncPatchLock flag
  // before loading zone.js/dist/zone-testing
  beforeEach(() => { jasmine.clock().install(); });
  afterEach(() => { jasmine.clock().uninstall(); });
  it('should auto enter fakeAsync', () => {
    // is in fakeAsync now, don't need to call fakeAsync(testFn)
    let called = false;
    setTimeout(() => { called = true; }, 100);
    jasmine.clock().tick(100);
    expect(called).toBe(true);
  });
});