Running jasmine tests for a component with NgZone dependency

Andrey picture Andrey · Nov 27, 2017 · Viewed 13.2k times · Source

How would I go ahead with running a jasmine test for the following component:

@Component({
  moduleId: module.id,
  selector: "testComp",
  template: "<div>{{value}}</div>",
})
export class TestComp {
  public value: string = "This is me";
  constructor(public zone: NgZone) {
    this.zone.run(() => console.log("zone is here"));
  }
}

The following fails with the Can't resolve all parameters for NgZone:

describe("test", () => {
    let fixture;
    let component;

beforeEach(async(() => {
    TestBed.configureTestingModule({
        declarations: [TestComp],
        schemas: [NO_ERRORS_SCHEMA],
        providers: [NgZone]
    }).compileComponents;
}));
beforeEach(() => {
    fixture = TestBed.createComponent(TestComp);
    component = fixture.debugElement.componentInstance;
});
it("should check that the component is created", () => {
    expect(component).toBeTruthy();
});

})

using Angular 4.1.3. I found the MockNgZone class @ https://no-shadow-angular-io.firebaseapp.com/docs/ts/latest/api/core/testing/MockNgZone-class.html. But it seems unavailable in the @angular/core/testing for this particular version: enter image description here

Anybody knows what I should do to test this component?

Regards

Answer

maxime1992 picture maxime1992 · May 17, 2018

If your problem is about runOutsideAngular because then you cannot use async or fakeAsync, the only thing you need to mock is that function and the following works well:

const ngZone = TestBed.get(NgZone);

spyOn(ngZone, 'runOutsideAngular').and.callFake((fn: Function) => fn());