Javascript 带karma的Angular 8测试组件失败

我正在尝试开始测试我的组件。我想测试的第一件事是

ngOnInit

是否调用了正确的服务

协议.组件.ts：

  constructor(private agreementService: AgreementService,
              private operatorService: OperatorService,
              private accountService: AccountService,
              private route: ActivatedRoute,
              private router: Router,
              private sessionService: SessionService,
              private settingsService: SettingsService) {
    this.agreementId = Number(this.route.snapshot.paramMap.get('agreementId'));
  }

  async ngOnInit() {
    this.session = await this.sessionService.getSession();
    this.settings = await this.settingsService.getSettings();

    this.operatorService.getOperators(this.session.bic).subscribe(data => {
      this.operators = data;
    });
  ...
  }

协议组件规范ts

import {AgreementComponent} from './agreement.component';
import {async, TestBed} from '@angular/core/testing';
import {ActivatedRoute, convertToParamMap, Router} from '@angular/router';
import {RouterTestingModule} from '@angular/router/testing';
import {AgreementService} from '../../../services/agreement.service';
import {AccountService} from '../../../services/account.service';
import {SessionService} from '../../../services/session.service';
import {SettingsService} from '../../../services/settings.service';

describe('agreementComponent', () => {
  let mockAgreementService: AgreementService;
  let mockOperatorService;
  let mockAccountService: AccountService;
  let mockRoute: ActivatedRoute;
  let mockRouter: Router;
  let mockSessionService: SessionService;
  let mockSettingsService: SettingsService;
  let component: AgreementComponent;

  beforeEach(async(() => {
    mockAgreementService = jasmine.createSpyObj(['getAgreement']);
    mockOperatorService = jasmine.createSpyObj(['getOperators']);
    mockAccountService = jasmine.createSpyObj(['getFeeAccounts']);
    mockRoute = jasmine.createSpyObj(['route']);
    mockRouter = jasmine.createSpyObj(['router']);
    mockSessionService = jasmine.createSpyObj(['getSession']);
    mockSettingsService = jasmine.createSpyObj(['getSettings']);

    TestBed.configureTestingModule({
      declarations: [AgreementComponent],
      imports: [
        RouterTestingModule
      ],
      providers: [
        {
          provide: ActivatedRoute, useValue:
            {
              snapshot: {
                paramMap: convertToParamMap({agreementId: '0'})
              }
            }
        },
      ]
    });

    component = new AgreementComponent(mockAgreementService, mockOperatorService, mockAccountService,
      mockRoute, mockRouter, mockSessionService, mockSettingsService);
  }));


  it('should call operators service', () => {
    component.ngOnInit();

    expect(mockOperatorService).toHaveBeenCalled();

  });
});

目前我得到：

失败：无法读取未定义的属性“paramMap”

TypeError:无法读取未定义的属性“ngOnInit”

---

我确信这段代码缺少很多东西才能正常工作，我就是不知道到底缺少了什么以及应该做些什么，因为谷歌搜索我的错误让我对大量不同的解决方案感到困惑。我对角度测试非常陌生，因此我想就如何以正确的方式编写测试提出一些建议。

采用不同的方法，创建存根，如中所述

已将可重用存根创建为：

等其他服务

根据需要在导入中使用路由测试模块

模拟

ActivatedRoute

和中的其他服务，如下所示：

我意识到没有一套合适的文章来学习角度测试，所以我写了这篇文章。我希望这会有帮助

更新： 要按照评论中的要求进行侦查，您可以执行以下操作：

  it('should call getOperators service in ngOnInit', () => {
    spyOn(component.operatorService,"getOperators").and.callThrough();
    component.ngOnInit();
    expect(component.operatorService.getOperators).toHaveBeenCalled();
    // you can also be more specific by using ".toHaveBeenCalledWith()"
  });

---

很好，谢谢，先生，真的很有帮助。我相信beforeach设置现在工作正常，现在我想测试

getOperators

from

operatorservice

是否正在

ngonit

上调用。我在想我该怎么做间谍。它应该在组件上还是在服务上？我尝试过这样创建：

spyOn（MockOperatorService.prototype，'getOperators'）。和.callThrough（）
component.ngOnInit（）
expect（MockOperatorService.prototype.getOperators）.toHaveBeenCalled（）但我得到了一个错误：
预期spy getOperators会被调用。
@developer1:m很高兴它有所帮助。我已经更新了答案。本文还介绍了如何使用
spy
。看看那些文章。也请将此标记为帮助其他人寻找类似问题的答案：）好的，谢谢！但它仍然没有像预期的那样工作。但是你确定我应该监视组件.操作器服务吗？我不应该监视我的模拟服务，然后期望调用模拟服务方法吗？嗯，这很奇怪。因为当我测试是否调用了
sessionService.getSession（）
时，我的测试通过了。但是如果我尝试测试是否调用了
settingsService.getSettings（）
，这就像在
ngOnInit
中调用相同一样，它会失败。有什么区别或问题吗？如果我正在测试是否调用了异步方法，我的
it
函数调用是否也应该是异步的？

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [AgreementComponent],
      imports: [
        RouterTestingModule
      ],
      providers: [
        {
          provide: ActivatedRoute, useValue:
            {
              snapshot: {
                paramMap: convertToParamMap({agreementId: '0'})
              }
            }
        },
        {provide: OperatorService , useClass: MockOperatorService},
        {....similarly for AgreementService etc etc}
      ]
    });
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(AgreementComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });



  it('should call getOperators service in ngOnInit', () => {
    spyOn(component.operatorService,"getOperators").and.callThrough();
    component.ngOnInit();
    expect(component.operatorService.getOperators).toHaveBeenCalled();
    // you can also be more specific by using ".toHaveBeenCalledWith()"
  });