Function createRouterScroller

packages/router/test/router_scroller.spec.ts:342–372

(
  {
    scrollPositionRestoration,
    anchorScrolling,
  }: {
    scrollPositionRestoration: 'disabled' | 'enabled' | 'top';
    anchorScrolling: 'disabled' | 'enabled';
  },
  extraProviders: any[] = [],
)

});

function createRouterScroller(
  {
    scrollPositionRestoration,
    anchorScrolling,
  }: {
    scrollPositionRestoration: 'disabled' | 'enabled' | 'top';
    anchorScrolling: 'disabled' | 'enabled';
  },
  extraProviders: any[] = [],
) {
  if (extraProviders.length > 0) {
    TestBed.configureTestingModule({providers: extraProviders});
  }

  const events = new Subject<Event | PrivateRouterEvents>();
  (TestBed.inject(NavigationTransitions) as Writable<NavigationTransitions>).events = events;

  const viewportScroller = TestBed.inject(ViewportScroller);
  spyOn(viewportScroller, 'getScrollPosition');
  spyOn(viewportScroller, 'scrollToPosition');
  spyOn(viewportScroller, 'scrollToAnchor');
  spyOn(viewportScroller, 'setHistoryScrollRestoration');
  setScroll(viewportScroller, 0, 0);

  const scroller = TestBed.runInInjectionContext(
    () => new RouterScroller({scrollPositionRestoration, anchorScrolling}),
  );
  scroller.init();

  return {events, viewportScroller};
}

function setScroll(viewportScroller: any, x: number, y: number) {
  viewportScroller.getScrollPosition.and.returnValue([x, y]);