Function createFixture

packages/core/test/acceptance/defer_spec.ts:187–244

* Given a template, creates a component fixture and returns * a set of helper functions to trigger rendering of prefetching * of a defer block.

(template: string)

 * of a defer block.
 */
function createFixture(template: string) {
  @Component({
    selector: 'nested-cmp',
    template: '{{ block }}',

    changeDetection: ChangeDetectionStrategy.Eager,
  })
  class NestedCmp {
    @Input() block!: string;
  }

  @Component({
    selector: 'simple-app',
    imports: [NestedCmp],
    template,

    changeDetection: ChangeDetectionStrategy.Eager,
  })
  class MyCmp {
    trigger = false;
    prefetchTrigger = false;
  }

  let loadingTimeout = 0;
  const deferDepsInterceptor = {
    intercept() {
      return () => {
        return [dynamicImportOf(NestedCmp, loadingTimeout)];
      };
    },
  };

  TestBed.configureTestingModule({
    providers: [
      ...COMMON_PROVIDERS,
      {provide: ɵDEFER_BLOCK_DEPENDENCY_INTERCEPTOR, useValue: deferDepsInterceptor},
    ],
  });

  clearDirectiveDefs(MyCmp);

  const fixture = TestBed.createComponent(MyCmp);
  fixture.detectChanges();

  const trigger = (loadingResourcesTime: number) => () => {
    loadingTimeout = loadingResourcesTime;
    fixture.componentInstance.trigger = true;
    fixture.detectChanges();
  };

  const triggerPrefetch = (loadingResourcesTime: number) => () => {
    loadingTimeout = loadingResourcesTime;
    fixture.componentInstance.prefetchTrigger = true;
    fixture.detectChanges();
  };

  return {trigger, triggerPrefetch, fixture};
}