Question

我是角单元测试的新手。测试方案：html中的表单视图值等于组件表单值。电子邮件值是通过共享值检索的，并在组件注册表单中使用。我可以使用反应形式从组件中检索电子邮件值，但是当尝试通过本机元素进行访问时，它为空。下面是component.ts

ngOnit(public serviceEmail) {
    this.assignEmailAvailable();
    this.createRegistration();

    }
assignEmailAvailable() {
 if(service.email){
    this.email = serviceEmail.email;
  }
 }   
createRegistration() {
   this.registerForm = new FormGroup({
       email:new FormControl({value:this.email})
    })
}

在component.spec.ts中，我将调用此函数并检查两个值是否相同。 component.spec.ts

 beforeEach(() => {
    fixture = TestBed.createComponent(RegisterComponent);
    component = fixture.componentInstance;
    service = TestBed.get(serviceEmail);
  });
it('Registration Form Creation', fakeAsync(() => {
    service.email = "dsf@gmail.com";

    fixture.detectChanges();

    component.assignEmailAvailable();
    component.createRegisterForm();

    fixture.detectChanges();
    fixture.whenStable().then(() => {
    const email = fixture.debugElement.query(By.css('input[id="email"]')).nativeElement;
//The value is empty even after creating the form using the component function
    expect(email.value).toBe(component.emailValue);
    });
//THis returns me the value set
    expect(component.registerForm.get('email').value).toBe(component.emailValue);
  }));

Answer 1

我花了大约2个小时来解决这个问题。根据我的经验，在beforeEach（）函数中存在一些需要解决的问题。首先，您需要将ReactiveFormsModule导入到TestBed中，以便更改检测可以正确执行所有操作。其次，您需要在beforeEach（）调用中手动运行ngOnInit（）和Fixture.detectChanges（）来设置表单。请参阅下面的我的beforeEach（）函数。我还包含了我的其余代码，其他有此问题的人可能会发现它们与之相关。

组件模板：


    <form [formGroup]='emailForm' (ngSubmit)='handleSubmit()'>
      <div class='form-group'>
        <label for='email'>Email address</label>
        <input type='email' class='form-control' id='email' placeholder='Enter email'
          formControlName='email'>

组件TS：

      constructor(
        private apiService: ApiService,
        private fb: FormBuilder,
        private router: Router
      ) { }
    
      ngOnInit() {
        this.initializeForm();
      }
    
      initializeForm(): void {
        this.formSubmitted = false;
        this.serverProcessing = false;
        this.emailForm = this.fb.group({
          email: ['', Validators.compose([Validators.required, Validators.email])]
        });
      }
    
      get email() {return this.emailForm.get('email');}

在Spec TS中，两个beforeEach（）调用：

      beforeEach(
        async(() => {
    
          apiServiceSpy = jasmine.createSpyObj('ApiService', ['sendResetPasswordEmail']);
          routerSpy = jasmine.createSpyObj('Router', ['navigateByUrl']);
    
          TestBed.configureTestingModule({
            declarations: [ SendPasswordResetEmailComponent ],
    
            // Need to import this if we're messing with Reactive Form inputs!!
            imports: [ReactiveFormsModule],
    
            providers: [
              {provide: ApiService, useValue: apiServiceSpy},
              {provide: Router, useValue: routerSpy},
              {provide: FormBuilder},
            ]
          })
          .compileComponents();
        })
      );
    
      beforeEach(() => {
        fixture = TestBed.createComponent(SendPasswordResetEmailComponent);
        component = fixture.componentInstance;
    
        // ngOnInit() doesn't get called automatically, so we have to do it ourselves
        component.ngOnInit();
    
        // Telling the fixture to detect changes is really important to correctly bind data
        // Do this after calling ngOnInit() so changes propagate to the template 
        fixture.detectChanges();
      });

样品测试规格：

      it('should have an error for no username', () => {
        const componentElement: HTMLElement = fixture.nativeElement;
        const emailInput: HTMLInputElement = componentElement.querySelector('input');
        emailInput.value = '@gmail.com';
        emailInput.dispatchEvent(new Event('input'));
        fixture.detectChanges();
        expect(component.email.errors.email).toBeTruthy('@gmail.com valid');
      });
    
      it('should have no error if the email is valid', () => {
        const componentElement: HTMLElement = fixture.nativeElement;
        const emailInput: HTMLInputElement = componentElement.querySelector('input');
        emailInput.value = 'joe@test.go';
        emailInput.dispatchEvent(new Event('input'));
        fixture.detectChanges();
        expect(component.email.errors).toBeFalsy('joe@test.go invalid');
      });

角单元测试-反应形式值未更新

1 个答案: