使用异步承诺测试 angular 2 项与 jasmine 的服务

Question

所以，我在测试 angular 2 服务时遇到了一些问题。我的测试被标记为通过，但我在控制台中收到此错误：

context.js:243 Unhandled Promise rejection: 'expect' was used when there was no current spec, this could be because an asynchronous test timed out ; Zone: ProxyZone ; Task: Promise.then ; Value: Error: 'expect' was used when there was no current spec, this could be because an asynchronous test timed out

我的服务使用 PouchDB，return是一个承诺。

这是我的服务：

import { Injectable } from '@angular/core';
import { Project } from './project';
declare var PouchDB:any;

@Injectable()
export class ProjectService {

  db: any;

  constructor() {
    if(navigator.vendor && navigator.vendor.indexOf('Apple') > -1){
      this.db = new PouchDB('projects', {adapter: 'fruitdown'});
    }else{
      this.db = new PouchDB('projects');
    }   
  }

  saveProject(project:Project): Promise<any>{
    return this.db.put(project);
  }

  getProjects(limit:number,skip:number): Promise<any> {
    return this.db.allDocs({
      include_docs: true,
      attachments: false,
      descending: true,
      limit: limit,
      skip: skip
    });
  }

}

这是我的规格

import { TestBed, inject, async } from '@angular/core/testing';

import { Project, ProjectService } from './index';

describe('ProjectService', () => {

  let project: Project;
  let service: ProjectService;

  let createFakeProject = function() {
    let project = new Project;
    project._id = 'iwhxu27i';
    project.name = 'foo bar';
    project.email = 'foo@b.ar';
    return project;
  }


  beforeEach(() => {
    const injector = TestBed.configureTestingModule({
      providers: [ProjectService]
    });

    service = injector.get(ProjectService);
    project = createFakeProject();

  });

  it('should be able to CREATE a new project (async)',
    async( (done) => {
    service.saveProject(project).then( 
      response => {
        expect(response).toEqual(project);
        done();
      } );

  }));

});

...好的，所以我已经摆弄了一段时间。我可能需要使用 fakeAsync 和 tick()？ fakeAsync 感觉不对，不过。看起来我应该在 .finally() 块中调用 done() 但 .finally() 不是一种方法。我刚开始使用 Jasmine 测试 Promises，所以也许我遗漏了一些明显的东西？如果您知道任何使用 angular2、jasmine 和 promises 的代码（或示例代码）；那会很有帮助。

我不想模拟 PouchDB 和 return 我自己的 Promise。

此测试应该会失败，因为 response != project;它没有，但我在我的控制台中收到错误消息。求助！

Answer 1

由 service.saveProject(project).then( 编辑的承诺 return 未等待，要么从方法中删除 async，并从测试中删除 return 这个承诺，要么等待承诺测试结果。

it('should be able to CREATE a new project (async)',
    async (done) => {
      let response = await service.saveProject(project)
      expect(response).toEqual(project);
  });

使用异步承诺测试 angular 2 项与 jasmine 的服务

testing angular 2 services with jasmine using async promises

promise

jasmine

pouchdb

typescript

angular