Question

我有一个UserManagementService，它暴露了Observable中的BehaviourSubject。

this.userSignInState$ = this.signInStateSubject.asObservable();

我在userSignInState组件中订阅了nav。

constructor(public userManagementService: UserManagementService, private fb:FormBuilder, private helper:HelperService) {
    this.userSignInStateSubscription = this.userManagementService.userSignInState$.subscribe(
          (result:Result)=> {
            console.log("In nav - result from user signin state ",result);
            let subscribed:UserSigninState = result.additionalInfo;
            console.log("new user signin state received:", subscribed);
            this.userLoggedIn = subscribed.isSignedIn;
            if(subscribed.isSignedIn && subscribed['additional-info'] !== ''){
              this.profile = JSON.parse(subscribed['additional-info']) as UserProfileAPI
            }
            if(!subscribed.isSignedIn && subscribed['additional-info'] !== ''){
            //  let error:ServerResponseAPI = JSON.parse(subscribed['additional-info']) as ServerResponseAPI
              //let errorMessage:string = this.helper.userFriendlyErrorMessage(error);
              this.navEvent.emit(new NavContext(subscribed['additional-info']));
            }
          },
        (error:ServerResponseAPI)=>{
            console.log("got error from the Observable: ",error);

           let errorMessage:string = this.helper.userFriendlyErrorMessage(error);
           this.navEvent.emit(new NavContext(errorMessage));
    //       this.userloggedIn =false;
      },
      ()=>{ //observable complete
        console.log("observable completed")
        //this.userloggedIn =false;
      });
  }

我想对nav进行单元测试。 spec应该测试component订阅了userSignInState$并正确处理Result。我该怎么做呢？由于这是单元测试，因此我不想使用真正的UserManagementService

我编写了以下规范

fit('should subscribe to user sign in state observable',()=>{
    let userManagementService = TestBed.get(UserManagementService);
    let navComponent:NavComponentComponent = component;
    console.log('component is ',navComponent);
    navComponent.userLoggedIn = false;
    let dummyUserProfile = new UserProfileAPI(new User('fn','ln','test@test.com'));
    userManagementService.signInStateSubject.next(new Result('success',(new UserSigninState(true,JSON.stringify(dummyUserProfile ))).toString));
    expect(navComponent.userLoggedIn).toBe(true)
  });

但是我收到错误消息Expected undefined to be true.

我不明白为什么userLoggedIn未定义。我在nav类中声明了它

export class NavComponentComponent implements OnInit  {

  userLoggedIn:boolean;
...
}

我在ngOnInit中设置了它。

ngOnInit(){

    this.userLoggedIn = false;
  ...
}

我也将订阅逻辑移至ngOnInit，但这也不起作用，并且给出了相同的结果。

Answer 1

问题出在我创建Result的方式上。我不应该将.toString与userSignInState一起使用。关于我在SO中发布的另一个问题，“对不带（）的.toString的引用只是对该函数的引用，因此，如果您记录下来，则可以获取该函数的代码。”另外，“ toString（）将不起作用，因为userSignInState没有有意义的字符串表示，并且默认为[object Object]”。我删除了toString，工作为additional-info的代码属于any

如何以角度对BehaviourSubject的订阅进行单元测试

1 个答案: