Question

我正在为Component with async service用角度7编写单元测试用例，并得到此错误：

错误：预期的间谍创建已被调用一次。被称为0 时间。

这是我的组件：

export class RegistrationComponent implements OnInit {

   submitRegistrationForm() {
        if (this.profileForm.invalid) {
          this.validateAllFields(this.profileForm);
        } else {
          // send a http request to save this data
          this.guestUserService.create(this.profileForm.value).subscribe(
            result => {
              if (result) {
                console.log('result', result);
                this.router.navigate(['/login']);
              }
            },
            error => {
              console.log('error', error);
            });
        }
  }

单元测试用例：

  describe('RegistrationComponent', () => {
      let component: RegistrationComponent;
      let fixture: ComponentFixture<RegistrationComponent>;
      let myService;
      let mySpy;

      beforeEach(async(() => {

        TestBed.configureTestingModule({
          declarations: [RegistrationComponent],
          imports: [ ],
          providers: [
            { provide: GuestUserService, useValue: new MyServiceStub() }]
        })
          .compileComponents();
      }));

      beforeEach(() => {
        fixture = TestBed.createComponent(RegistrationComponent);
        component = fixture.componentInstance;
        fixture.detectChanges();
      });

 it('should submit Registration Form', async(inject([Router], (router) => {
    myService = TestBed.get(GuestUserService);
    mySpy = spyOn(myService, 'create');
    spyOn(router, 'navigate');
    spyOn(component, 'submitRegistrationForm');


component.profileForm.controls['firstName'].setValue('Arjun');
    component.profileForm.controls['lastName'].setValue('Singh');
    component.profileForm.controls['password'].setValue('12345678');
    component.profileForm.controls['confirmPassword'].setValue('12345678');
    component.submitRegistrationForm();

    expect(component.profileForm.invalid).toBe(false);

    expect(component.submitRegistrationForm).toHaveBeenCalled();

    expect(myService).toBeDefined();
    expect(mySpy).toBeDefined();
    expect(mySpy).toHaveBeenCalledTimes(1); // Getting error is this
    expect(router.navigate).toHaveBeenCalled();
  })
  ));

我试图将间谍减速移动到beforeEach，但仍然会给出相同的错误。

如何解决此错误？

谢谢！

Answer 1

预期被调用的间谍创建不是错误，而是测试失败。

之所以发生这种情况，是因为您没有使用callThrough（）;要么在您的间谍上。

 it('should submit Registration Form', async(inject([Router], (router) => {

    myService = TestBed.get(GuestUserService);
    mySpy = spyOn(myService, 'create').and.callThrough(); //callThrough()

    spyOn(router, 'navigate');

    spyOn(component, 'submitRegistrationForm').and.callThrough(); //callThrough()


    component.submitRegistrationForm();

    expect(component.profileForm.invalid).toBe(false);

    expect(component.submitRegistrationForm).toHaveBeenCalled();

    expect(myService).toBeDefined();
    expect(mySpy).toBeDefined();
    expect(mySpy).toHaveBeenCalledTimes(1); 
    expect(router.navigate).toHaveBeenCalled();
  })
  ));

Answer 2

SpyOn将帮助您设置在测试中调用该函数时应如何反应。基本上，这是创建模拟的茉莉花方式。

在您的情况下，您已定义了在调用服务功能（即callThrough）时应执行的测试。问题在于，您还需要对服务函数（或调用服务方法的范围函数）进行操作，以触发将调用Through的SpyOn。

[
    ['id' => 1, 'name' => 'Spend', 'amount' => 10.52],
    ['id' => 2, 'name' => 'Spend', 'amount' => 10.55],
]

}）;

这是一个简单的测试，我们将模拟SpyOn对字符串的响应

it('load snapshot',function(){

  //setup
  spyOn(MyService, 'loadSomething').and.callThrough(); //statement 2

  //act

  //either call the scope function which uses the service 
  //$scope.yourServiceCallFunction();

  //or call the service function directly
  MyService.loadSomething(1); //this will callThrough

错误：预期的间谍创建已被调用

2 个答案: