嘲笑男生

Question

我在index.js中有如下明确的POST路由设置

  import * as Busboy from 'busboy';
  public publish = async (req: Request, res: Response) => {
    const busboy = new Busboy({ headers: req.headers });
    const pl = { title: '' };
    busboy.on('field', (fieldname, val) => {
      switch (fieldname) {
        case 'title':
          pl.title = val;
          break;
      }
    });
    busboy.on('file', (fieldname, file, filename, encoding, mimetype) => {
      // Process files
    });
    busboy.on('finish', async () => {
      // Process request
      res.send({payload: pl});
    });
  } 

在使用indexest的test index.test.js中，我如何模拟此模块，以便可以验证包含请求中发送的表单字段title的响应？ 目前，我使用jest.mock('busboy');，但由于这个原因，没有任何调用。

jest.mock('busboy');
let service: ServiceController;
describe('Mosaic Research Capture Service', () => {
it('should publish', async () => {
 service = new ServiceController();
 const req = {
      headers: {
        'Content-Type': 'multipart/form-data'
      },
      body: {}
 };
 const res = {
  send: jest.fn()
 };
 await service.publish(req, res);
});
});

React客户端如下调用此请求

 const formData = new FormData();
 formData.append('title', 'SomeTitle');
 const header = {
   credentials: 'include',
   'Content-Type': 'multipart/form-data',
 };
 const response =  await axios.post('/publish, formData, header); 

Answer 1

您需要一个“技巧”来模拟event-listener动作。问题https://github.com/airbnb/enzyme/issues/426

您多次滥用async/await，如果您使用Promises，只需使用这些关键字。

这是针对您的情况的建议更新：

index.js：只需删除所有async关键字

 import * as Busboy from 'busboy';
  public publish = (req: Request, res: Response) => {
    const busboy = new Busboy({ headers: req.headers });
    const pl = { title: '' };
    busboy.on('field', (fieldname, val) => {
      switch (fieldname) {
        case 'title':
          pl.title = val;
          break;
      }
    });
    busboy.on('file', (fieldname, file, filename, encoding, mimetype) => {
      // Process files
    });
    busboy.on('finish', () => {
      // Process request
      res.send({payload: pl});
    });
  } 

index.test.js

import { ServiceController } from "./handler";
import * as Busboy from 'busboy';

jest.mock('busboy');
describe('Mosaic Research Capture Service', () => {
  let service: ServiceController;
  const mockedEvenMap = {};

  beforeAll(() => {
    Busboy.mockImplementation(() => {
      return { // mock `on` event of Busby instance
        on: (event, callback) => {
          mockedEvenMap[event] = callback;
        },
      };
    });

    service = new ServiceController();
  });

  afterAll(() => {
    Busboy.mockRestore();
  });

  it('should publish', () => {
    const expectedTile = "MY_TITLE";
    const filenameToTest = 'title';

    const req = {
      headers: {
        'Content-Type': 'multipart/form-data'
      },
      body: {}
    };
    const res = {
      send: jest.fn()
    };
    service.publish(req, res); // remove await

    // fire simulate event
    mockedEvenMap['field'](filenameToTest, expectedTile);
    mockedEvenMap['finish']();

    // you expect send function will be call with a payload with includes the title
    expect(res.send).toBeCalledWith({ payload: {title: expectedTile} });
  });
});