如何为 public 静态方法编写 jasmine-karma 测试用例？

Question

我正在为一个服务编写 jasmine-karma 测试用例，其中的方法本质上是 public 静态的。我如何无法访问它们或在 spec.ts 文件中为它们编写测试用例。谁能告诉我怎么做？

这是我在app.service.ts

中的方法

public static getModifiedDate(dateVal: any): string {
    if ('' === dateVal) {
      return null;
    }
    const year = dateVal.substring(
      dateVal.lastIndexOf('/') + 1,
      dateVal.length
    );
    const month = dateVal.substring(0, dateVal.indexOf('/'));
    const date = dateVal.substring(
      dateVal.indexOf('/') + 1,
      dateVal.lastIndexOf('/')
    );
    return year + '-' + month + '-' + date;
  }

在 spec.ts 文件中，我无法为这个函数编写测试用例，因为我试过，

describe('AppService', () => {
  let service: AppService;
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      imports: [HttpClientTestingModule],
      providers: [RestClientService, AppService]
    });
    service = TestBed.get(AppService);
  }));

  it('getModifieddate should return date in the expected format', () => {
    const date = service.getModifiedDate('04/20/2017');
    expect(date).toEqual('2017-04-20');
  }); 
});

显示错误，因为 getModifiedDate 是 public 静态方法。解决这个问题的正确方法是什么？

Answer 1

您应该以静态方式调用静态方法：AppService.getModifiedDate。测试可以简化如下：

describe('AppService', () => {
  it('getModifieddate should return date in the expected format', () => {
    const date = AppService.getModifiedDate('04/20/2017');
    expect(date).toEqual('2017-04-20');
  }); 
});

Answer 2

有几项您可以尝试，这里是：

it('getModifieddate should return date in the expected format', () => {
    const date = (service as any).getModifiedDate('04/20/2017');
    expect(date).toEqual('2017-04-20');
  });

it('getModifieddate should return date in the expected format', () => {
    spyOn(service as any, 'getModifiedDate').and.callFake(() => {return '2017-04-20'; });
    const date = (service as any).getModifiedDate('04/20/2017');
    expect(date).toEqual('2017-04-20');
  });

it('getModifieddate should return date in the expected format', () => {
    const date = AppService.getModifiedDate('04/20/2017');
    expect(date).toEqual('2017-04-20');
  });

希望这对您有所帮助。如果您有任何疑问，请告诉我。

如何为 public 静态方法编写 jasmine-karma 测试用例？

How do I write jasmine-karma test cases for public static methods?

jasmine

typescript

karma-jasmine

angular