进行角度单位测试时出错?

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我在进行Angular单元测试时遇到错误。我正在尝试测试创建组件请查看下面的错误文件并让我知道为什么我面临这一点,我还导入与模块的提供者和导入相关的服务。

单元测试时,Karma会显示以下错误。我想我错过了一些东西

TypeError: Cannot read property 'userName' of undefined
at Object.eval [as updateRenderer] (ng:///DynamicTestModule/ProfilePersonalInformationComponent.ngfactory.js:72:38)
at Object.debugUpdateRenderer [as updateRenderer] (webpack:///./node_modules/@angular/core/esm5/core.js?:14909:21)
at checkAndUpdateView (webpack:///./node_modules/@angular/core/esm5/core.js?:14023:14)
at callViewAction (webpack:///./node_modules/@angular/core/esm5/core.js?:14369:21)
at execEmbeddedViewsAction (webpack:///./node_modules/@angular/core/esm5/core.js?:14327:17)
at checkAndUpdateView (webpack:///./node_modules/@angular/core/esm5/core.js?:14019:5)
at callViewAction (webpack:///./node_modules/@angular/core/esm5/core.js?:14369:21)
at execEmbeddedViewsAction (webpack:///./node_modules/@angular/core/esm5/core.js?:14327:17)
at checkAndUpdateView (webpack:///./node_modules/@angular/core/esm5/core.js?:14019:5)
at callViewAction (webpack:///./node_modules/@angular/core/esm5/core.js?:14369:21)

为了解决上面的错误,我创建了PerosnalInfoStub类,但它没有用。

component.spec.ts文件

describe('ProfilePersonalInformationComponent', () => {
  let component: ProfilePersonalInformationComponent;
  let fixture: ComponentFixture<ProfilePersonalInformationComponent>;
  let personalInfo : PersonalInfo;

  class PersonalInfoStub{
      personalInfo: Subject<any[]> = new Subject<any[]>();



  }

  beforeEach(async(() => {
    TestBed.configureTestingModule({

        imports: [FormsModule, SharedModule, HttpModule, BrowserModule],
      declarations: [ ProfilePersonalInformationComponent ],
      providers: [
        {
           provide: PersonalInfo, useClass: PersonalInfo
        },

        {
            provide: NotificationService, useClass: NotificationService
        },

        {
            provide: LoginService, useClass: LoginService
        },
        {
            provide: ConfigService, useClass: ConfigService
        }

    ],


    })
    .compileComponents();
  }));

  beforeEach(() => {

    fixture = TestBed.createComponent(ProfilePersonalInformationComponent);
    component = fixture.componentInstance;

    fixture.detectChanges();
  });

  it('should create', () => {

    expect(component).toBeTruthy();
  });

个人info.ts

export class PersonalInfo {
  userName: string;
}

组件的类文件

ProfilePersonalInformationComponent implements OnInit {




  @Input() personalInfo: PersonalInfo;
  @Input() loadingData;
  savingData: boolean;

  passwordHelpTextArray: string[];
  passwordHelpText: string;
  formErrors: any = {
    username: {
      error: '',
      errorMessage: ''
    },
    currentPassword: {
      error: '',
      errorMessage: ''
    },
    newPassword: {
      error: '',
      errorMessage: ''
    },
    verifyNewPassword: {
      error: '',
      errorMessage: ''
    }
  };

  updatedUsername: string = '';
  existingPassword: string = '';
  newPassword: string = '';
  reEnterNewPassword: string = '';

  constructor(private personalInfoService: PersonalInformationService,
    private notificationService: NotificationService) { }

  ngOnInit(): void {
    this.populateInfo();
  }

  populateInfo() {
    setTimeout(() => {
      if (this.loadingData === false) {
        this.updatedUsername = this.personalInfo.userName;
      } else {
        this.populateInfo();
      }

    }, 500);
  }

用户名的Html代码

 <div class="col-sm-2">
        <h3>Username</h3>
        <p>{{personalInfo.userName}}</p>
      </div>
      <div class="col-sm-2">
        <h3>Password</h3>
        <p>********</p>
      </div>
提问于
用户回答回答于

你应该在测试时模拟组件数据,尤其是@Input通常从父组件获取值的属性。但是在单元测试中,你必须自己模拟它,因为没有涉及父组件。

beforeEach(() => {
    fixture = TestBed.createComponent(ProfilePersonalInformationComponent);
    component = fixture.componentInstance;
    // mock input data
    component.personalInfo = {"userName" : "XYZ"};
    fixture.detectChanges();
});

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