Angular 变量始终未定义为wait Jasmine

我需要测试一个函数，在该函数中创建一个变量并为其赋值

但有效载荷常数始终未定义

活动卡.component.ts

async ngOnInit() {
    const { uid } = await this.auth.currentUser
    const { payload } = await this.firestore.surveysUsers(this.survey.id).doc(uid).snapshotChanges().pipe(first()).toPromise();
    this.completed = payload.exists
  }

beforeEach(waitForAsync(() => {
    fireStoreServiceMock.surveysUsers.and.returnValue({ 
      doc: () => { return {
        snapshotChanges: () => { return {
          pipe: () => { return {
            toPromise: () => { return { exists: true }}
          }}
        }}
      }}
    });
  }));

describe('tests in delete', () => {
    it('should update surveys', fakeAsync(() => {
      fixture.detectChanges();
      component.delete().then(() => {
      });
      fixture.detectChanges();
      tick();

      expect(fireStoreServiceMock.surveys).toHaveBeenCalled();
      expect(snackBarMock.open).toHaveBeenCalled();
    }));
  });

组件卡.组件规范ts

async ngOnInit() {
    const { uid } = await this.auth.currentUser
    const { payload } = await this.firestore.surveysUsers(this.survey.id).doc(uid).snapshotChanges().pipe(first()).toPromise();
    this.completed = payload.exists
  }

beforeEach(waitForAsync(() => {
    fireStoreServiceMock.surveysUsers.and.returnValue({ 
      doc: () => { return {
        snapshotChanges: () => { return {
          pipe: () => { return {
            toPromise: () => { return { exists: true }}
          }}
        }}
      }}
    });
  }));

describe('tests in delete', () => {
    it('should update surveys', fakeAsync(() => {
      fixture.detectChanges();
      component.delete().then(() => {
      });
      fixture.detectChanges();
      tick();

      expect(fireStoreServiceMock.surveys).toHaveBeenCalled();
      expect(snackBarMock.open).toHaveBeenCalled();
    }));
  });

错误

Error: Uncaught (in promise): TypeError: Cannot read property 'exists' of undefined
TypeError: Cannot read property 'exists' of undefined
    at CampaignsCardComponent.<anonymous> (http://localhost:9876/_karma_webpack_/webpack:/src/app/modules/campaigns/pages/campaigns-card/campaigns-card.component.ts:43:4)
    at Generator.next (<anonymous>)
    at fulfilled (http://localhost:9876/_karma_webpack_/webpack:/node_modules/tslib/tslib.es6.js:71:42)
    at ZoneDelegate.invoke (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:372:1)
    at ProxyZoneSpec.onInvoke (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/proxy.js:126:1)
    at ZoneDelegate.invoke (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:371:1)
    at Object.onInvoke (http://localhost:9876/_karma_webpack_/webpack:/node_modules/@angular/core/fesm2015/core.js:28535:1)
    at ZoneDelegate.invoke (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:371:1)
    at Zone.run (http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:134:1)
    at http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:1276:1

错误：未捕获（承诺中）：TypeError:无法读取未定义的属性“exists”
TypeError:无法读取未定义的属性“exists”
在活动斯卡德组件。(http://localhost:9876/_karma_webpack_/webpack:/src/app/modules/campaigns/pages/campaigns-卡片/活动卡片.组件ts:43:4）
在Generator.next（）处
至少(http://localhost:9876/_karma_webpack_/webpack:/node_modules/tslib/tslib.es6.js:71:42)
在ZoneDelegate.invoke(http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:372:1）
在Proxyzonspect.onInvoke(http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/proxy.js:126:1)
在ZoneDelegate.invoke(http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:371:1）
在Object.onInvoke(http://localhost:9876/_karma_webpack_/webpack:/node_modules/@angular/core/fesm2015/core.js:28535:1）
在ZoneDelegate.invoke(http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:371:1）
在Zone.run(http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-常青树.js:134:1）
在http://localhost:9876/_karma_webpack_/webpack:/node_modules/zone.js/dist/zone-evergreen.js:1276:1

差不多了。问题是这是一个可观察的，您不应该在其上模拟

管道

函数，而是从函数调用返回一个可观察的

试试这个：

import { of } from 'rxjs';
....
beforeEach(waitForAsync(() => {
    fireStoreServiceMock.surveysUsers.and.returnValue({ 
      doc: () => { return {
        snapshotChanges: () => of({ exists: true }) // mock the observable with of
        }}
      }}
    });
  }));

---

我可能把括号（{}）和更改弄乱了，但这应该可以做到。

我做了这个更改，但问题仍然是一样的。我设法解决了这个问题，因为它是一个常量，我需要返回一个内部存在的有效负载对象。