Question

我已经定义了自己的表单类，该类通过以下构造函数扩展了FormGroup：

public constructor(/* params */) {
    function myValidator(): ValidatorFn {
      //return validator function
    }

    super({ /* controls */}, [myValidator()]);
  }

当我运行我的应用程序时，它可以工作，但是当我对其运行单元测试时，它在超级构造函数上中断，并且出现以下错误消息：

TypeError：如果没有'new'，则无法调用类构造函数FormGroup

它是在组件的ngOnInit函数中构造的，就像这样：

ngOnInit() {
    this.myForm = new MyForm(/* args */);
    //call service
  }

我的规格文件：

let component: MyComponent;
let fixture: ComponentFixture<MyComponent>;

const myArray = ['object'];
let myServiceMock: any;
let getCallSpy: any;

describe('ErdwwLoggingComponent', () => {

  beforeEach(async(() => {
    myServiceMock = jasmine.createSpyObj('MyService', ['getCall']);
    getCallSpy = myService.getCall.and.returnValue( of(myArray) );

    TestBed.configureTestingModule({
      declarations: [
        MyComponent
      ],
      providers: [
        { provide: MyService, useValue: myServiceMock }
      ]
    });

    TestBed.overrideComponent(MyComponent, {
      remove: {
        templateUrl: './my.component.html'
      },
      add: {
        template: '<div>test</div>'
      }
    });

    TestBed.compileComponents().then(() => {
      fixture = TestBed.createComponent(MyComponent);
      component = fixture.componentInstance;
    });
  }));

  //succeeds
  it('should have spies defined', () => {
    expect(myServiceMock.getCall).toBeDefined('myServiceMock.getCall not defined');
    expect(getCallSpy).toBeDefined('getCallSpy not defined');
  });

  describe('initialisation', () => {
    //succeeds
    it('should be defined', () => {
      expect(component).toBeDefined();
    });

    //fails
    it('should call getCall', () => {
      // I also tried explicitly calling component.ngOnInit();
      fixture.detectChanges(); // onInit()

      expect(myServiceMock.getCall).toHaveBeenCalled();
    });
  });
});

Answer 1

问题出在我的tsconfig.spec.json文件中。

在compilerOptions中，我有"target": "es5"，当我删除该错误后，我不再收到错误消息。

在ngOnInit中调用时，Jasmine如何使用FormGroup超级构造函数？

1 个答案: