angular - 测试 angular if else block 和 subscribe(response => {} block in jasmine

Question

我在编写组件方法测试用例时遇到问题。

如何在 subscribe((res) => {///block} 和 ToasterService 中测试 Angular 组件方法 if else block 里面。

我在 component.ts 文件中调用了 Angular 服务方法。在服务调用 subscribe(response=>{} 中。

我已经验证了 if else block 中的响应值，并根据结果显示 toastr 消息，但我的 karma 报告说:response=> function not covered 和 inside if else block not 语句未被覆盖。

组件.ts

constructor(private userService: UserService,
    private toastr: ToastrService) { }
sortUsers(sortKey: string) {
    this.userService.getSortUserList(sortKey).subscribe((res) => {
      if(res.Success){
        this.userService.users = res.Data as User[];
      }else{
        this.toastr.error(res.Message);
      }
      
    });
  }

组件.spec.ts

it('call sortUser when users are sorted', () => {
    const users: User[] = [{
      User_Id: 1,
      First_Name: 'Madhu Ranjan',
      Last_Name: 'Vannia Rajan',
      Employee_Id: 12345,
      Project_Id: 1,
      Task_Id:1,
      _id: 'xcv'
    }];

    component.sortUsers('First_Name');
    const res = {Success: true, Data: users}
    spyOn(service, 'getSortUserList').and.returnValue(of({Success: true, Data: users}));    
  });

希望下面的代码块也能被 jasmine 测试:

subscribe((res) => {
      if(res.Success){
        this.userService.users = res.Data as User[];
      }else{
        this.toastr.error(res.Message);
      }
      
    });

karma 报告:

Karma report

Answer 1

尝试

constructor(
    public userService: UserService,
    public toastr: ToastrService) { 
}

在规范文件中:

it('call sortUser when users are sorted with success', () => {
    const users: User[] = [{
      User_Id: 1,
      First_Name: 'Madhu Ranjan',
      Last_Name: 'Vannia Rajan',
      Employee_Id: 12345,
      Project_Id: 1,
      Task_Id:1,
      _id: 'xcv'
    }];    
    const res = {Success: true, Data: users}
    spyOn(component.userService, 'getSortUserList').and.returnValue(of(res));  
    spyOn(component.toastr,'error').and.callThrough();
    component.userService.users = undefined;
    component.sortUsers('First_Name');
    expect(component.userService.users).toBeDefined()   
    expect(component.toastr.error).not.toHaveBeenCalled()  
  });

it('call Error Toaster in sortUser() when users are sorted', () => {
    const res = {Message: 'error_msg'}
    spyOn(component.userService, 'getSortUserList').and.returnValue(of(res));  
    spyOn(component.toastr,'error').and.callThrough();
    component.userService.users = undefined;
    component.sortUsers('First_Name');
    expect(component.userService.users).not.toBeDefined()   
    expect(component.toastr.error).toHaveBeenCalledWith('error_msg')  
  });

由于您是 karama 的新手，我强烈建议您使用 read this article其中包含一组文章，用于在底部页面处理 Angular 单元测试。