如何使用笑话功能发送响应？ 它给出了异步回调错误

Question

我尝试使用玩笑来模拟模型响应。 它将进入我的jest.mock.createMondayBox函数中，并且可以显示“ hello world”，这意味着它可以真正进入替换原始模型的模拟模型中。

车型/ mondayModel.js

var mondayModel = function() {
  function createBox (req, payload, callback) { 
   ...
   boxClient.request(req, {
     method: 'POST'
     path:
     body: 
     headers: { }
   }, function(error, response) {
      if(error || (response.statusCode && response.statusCode !== 200)) { 
        return callback(new ErrorObject({
           errorName:'createBoxFailure', 
           errorMessage: 'Error in creating box'
        })
      }
      return callback(null, {resultSet: response.body})
   })

  }
  function fnB (req, callback) { }
  function fnC (req, callback) { }
  function fnD (req, callback) { }
  return {
    createBox: createBox,
    fnB: fnB,
    fnC: fnC,
    fnD: fnD
  }
}

module.exports = mondayModel

控制器/ boxController.js

var MondayModel = require('../models/mondayModel');


function createMondayBox(req, res, next) {
   ...
   var mondayModel = new MondayModel();
   mondayModel.createBox(req, payload, function(error, result) {

      if(error) {
         res.json({'status': 'BADREQUEST', 'statusCode': 400})

      } else {
         var mondaybox = result.resultSet.mondayboxes && result.resultSet.mondayboxes[0]

         var mappedResponse = Response.mapCreateMondaybox(req, resultSet);
         utils.logKK(req, utils.getKK(mappedResponse.mondayboxes[0]))
         res.json(mappedResponse);
      }

   ...
   }
}

boxController-test.jest

let boxController = null

describe('money tracker', () => {
    beforeAll(() => {        
        jest.mock('../../../../models/mondayBox',
            () => function mondayBoxModel() {
               console.log("hello world")
               return {
                createBox: (req, payload, callback) => {
                  return callback(null, {
                        resultSet: {
                            mondayboxes: [{ name: '1' }, { name: '2' }]
                        },
                        json: jest.fn()
                    })}
                fnB: jest.fn(),
                fnC: jest.fn(),
                fnD: jest.fn()
                }
               }
        }))    
    )
        boxController = require('../controllers/boxController')
    })

    test('success case', done => {
       const req = {}
       const res = new Promise(r =>
         r({ json: jest.fn(), status: jest.fn() })
       )
       mondayBoxController.createMondayBox(req, res, (cbErr, cbRes) => {
          expect(res.json).toBeCalled();
          done()
       }) 
    }
}

TypeError：res.json不是函数

我可以知道如何解决这个问题吗？ 如何编写模拟模型响应？ 谢谢

Answer 1

首先，您只需要测试控制器，因此您应该

将控制器更新为

var MondayModel = require('../models/mondayModel');


function createMondayBox(req, res, next) {
 ...
 var mondayModel = new MondayModel();
 mondayModel.createBox(req, payload, function(error, result) {

   if(error) {
     res.json({'status': 'BADREQUEST', 'statusCode': 400})

   } else {
     var mondaybox = result.resultSet.mondayboxes && 
     result.resultSet.mondayboxes[0]

     var mappedResponse = Response.mapCreateMondaybox(req, resultSet);
     utils.logKK(req, utils.getKK(mappedResponse.mondayboxes[0]))
     res.json(mappedResponse);
     next();
   }

  ...
 }
}

并在测试文件中：

import {createRequest, createResponse}  from 'node-mocks-http'
import boxController from 'controller/boxController.js'
import mondayBoxModal from 'models/mondayBox';

jest.mock('models/mondayBox', () => () => ({ createBox: (req, payload, cb) => cb(null, { resultSet: { mondayboxes: ['resultsData']} } }));

describe('money tracker', () => {
 let req;
 let res;
 let next = jest.fn;
 beforeEach(() => {
    jest.clearAllMocks();
    req  = createRequest({
      method: 'GET',
      url: '/user/42',
      params: {
       id: 42
      }
    });

    res = httpMocks.createResponse();
    res.json = jest.fn;

 })

 test('success case', done => {
   const req = {}

   mondayBoxController.createMondayBox(req, res, (cbErr, cbRes) => {
      expect(res.json).toBeCalled();
      done()
   })
}

}

Answer 2

您的函数transfer(req, res, next)接受3个参数，并在调用boxController.transfer(req, {}, fn)传递空对象时使用res.json() 。 它可能在这里无声地失败了。

在您的样本中， transfer根本没有调用。

请确保您的示例准确地类似于实际代码。

更新

它与异步无关

如果你写这个

const res = new Promise(r =>
  r({ json: jest.fn(), status: jest.fn() })
)
mondayBoxController.createMondayBox(req, res, (cbErr, cbRes) => {
  expect(res.json).toBeCalled();
  done();
})

然后

mondayModel.createBox(req, payload, function (error, result) {
  console.log(res); // Promise, which has no json method
  console.log(res.json); // undefined
  // but
  console.log(await res); // the desired mocked res obj
  // btw this is incorrect usage of await
  if (error) {
    res.json();
  } else {
    ...
  }
});

mondayModel.createBox的回调中的res就是您传递给mondayBoxController.createMondayBox(req, res, handler) 。

相反，这样做

const res = {
  json: jest.fn(); // or whatever behaviour you desire
};
mondayBoxController.createMondayBox(req, res, handler);