Branches on constructor not covered

问题:

I am creating my unit tests with Jasmine and I have a question about the branch covered.

Does anyone know why the code part shows that the branches are not covered as we can see below?

This is the unit test:

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

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ MyComponent ],
      imports: [ MaterializeModule, FormsModule, ReactiveFormsModule, HttpModule ],
      providers: [
        MyService,
        FormBuilder
      ]
    })
    .compileComponents();
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(MyComponent);
    component = fixture.componentInstance;
    slotsService = TestBed.get(MyService);
    fixture.detectChanges();
  });

  function updateForm(name, surname) {
    component.myForm.controls['name'].setValue(name);
    component.myForm.controls['surname'].setValue(name);
  }

  it('should create', () => {
    expect(component).toBeTruthy();
  });
}

回答1:

I've had the same issue for months from the moment I upgraded my projects to angular 4. Unfortunately it is a bug with the angular-cli version 1 and angular 4.

This bug is already logged in the angular-cli project: Test-coverage says that coverage is not 100%, but it truly is! #5871. Unfortunately at the moment, this issue is still open.

This is a snapshot from that logged issue, which matches the one you are asking about:

回答2:

If you are facing this problem and , nevertheless, want to reach 100% branch coverage, there is at least a workaround available (see https://github.com/angular/angular-cli/issues/5526#issuecomment-324429322).

Simply add /* istanbul ignore next */ after the class export (without any line breaks):

export class InternalComponent {
    constructor(private authService: any) { 
    }
} /* istanbul ignore next */

回答3:

For Angular 2+ projects, this is now fixed if you upgrade to Angular CLI 1.5.

GitHub post: https://github.com/angular/angular-cli/issues/5526