Sails.js：无法将辅助程序存根用于单元测试

编程问答 2022-08-11

问题描述

节点版本：v12.18.3 帆船版本 （帆船）：1.2.3

执行单元测试时，我无法使用帆助手。我有一个助手来处理与数据库的所有通信。而且，我有一个使用此帮助程序的API。在我的测试中，我试图像这样使用sinon对助手进行打桩：

API：

fn: async function (inputs,exits) {
 // Stuff done here
 // I need to stub this helper
 let result = await sails.helpers.arangoQuery.with({
      requestId: REQUEST_ID,query: query,queryParams: params
    });
  
}

我的测试：

describe('Get Organization',() => {
    it('Server Error - Simulates a failure in fetching the data from arangoDB',(done) => {
        sinon.stub(sails.helpers,'arangoQuery').returns(null,{status: "success"});

        supertest(sails.hooks.http.app)
            .get('/organization')
            //.expect(200)
            .end((error,response) => {
              return done()
            }
      })
})

运行测试时，出现以下错误：

  error: Error: cannot GET /organization (500)
      at Response.toError (/opt/designhubz/organization-service/node_modules/superagent/lib/node/response.js:94:15)
      at ResponseBase._setStatusProperties (/opt/designhubz/organization-service/node_modules/superagent/lib/response-base.js:123:16)
      at new Response (/opt/designhubz/organization-service/node_modules/superagent/lib/node/response.js:41:8)
      at Test.Request._emitResponse (/opt/designhubz/organization-service/node_modules/superagent/lib/node/index.js:752:20)
      at /opt/designhubz/organization-service/node_modules/superagent/lib/node/index.js:916:38
      at IncomingMessage.<anonymous> (/opt/designhubz/organization-service/node_modules/superagent/lib/node/parsers/json.js:19:7)
      at IncomingMessage.emit (events.js:327:22)
      at endReadableNT (_stream_readable.js:1220:12)
      at processticksAndRejections (internal/process/task_queues.js:84:21) {
    status: 500,text: '{}',method: 'GET',path: '/organization'
  }

根本没有关于此问题的文档。谁能告诉我如何向助手打桩？

解决方法

风帆助手使用machine，这会使存根变得更加棘手。

AFAIK ，通过对真正的 fn 函数进行存根，可以替代存根帆助手，因为计算机将调用助手的fn函数。>

更新：更改使用超级测试的示例。

例如：

  • 我使用HelloController创建端点GET / hello，
  • 我使用helper's example中的帮助程序format-welcome-message，
  • 我为端点GET / hello创建测试规范。
  • 我使用不带lifecycle.js的mocha来运行它，但将生命周期嵌入了测试规范（reference）中。

端点GET / hello定义：

// File: HelloController.js
module.exports = {
  hello: async function (req,res) {
    // Dummy usage of helper with predefined input test.
    const output = await sails.helpers.formatWelcomeMessage.with({ name: 'test' });
    // Just send the output.
    res.send(output);
  }
};

不要忘记在config / routes.js中添加路由：'GET /hello': 'HelloController.hello'。

测试规范包含3种情况（正常调用，存根错误和存根成功）。

// File: hello.test.js
const sails = require('sails');
const sinon = require('sinon');
const { expect } = require('chai');
const supertest = require('supertest');

describe('Test',function () {
  let fwm;
  // Copy from example testing lifecycle.
  before(function(done) {
    sails.lift({
      hooks: { grunt: false },log: { level: 'warn' },},function(err) {
      if (err) { return done(err); }
      // Require helper format welcome message here!
      fwm = require('../api/helpers/format-welcome-message');
      return done();
    });
  });

  after(function(done) {
    sails.lower(done);
  });

  it('normal case',function (done) {
    // Create spy to make sure that real helper fn get called.
    const spy = sinon.spy(fwm,'fn');
    supertest(sails.hooks.http.app)
      .get('/hello')
      .expect(200)
      // Expect endpoint output default value.
      .expect('Hello,test!')
      .end(function() {
        // Make sure spy is called.
        expect(spy.calledOnce).to.equal(true);
        // Restore spy.
        spy.restore();
        done();
      });
  });

  it('case stub error',function (done) {
    // Stub the real fn function inside custom helper.
    const stubError = sinon.stub(fwm,'fn');
    stubError.callsFake(async function (input,exits) {
      // Setup your error here.
      exits.error(new Error('XXX'));
    });

    supertest(sails.hooks.http.app)
      .get('/hello')
      .expect(500)
      .end(function() {
        // Make sure stub get called once.
        expect(stubError.calledOnce).to.equal(true);
        // Restore stub.
        stubError.restore();
        done();
      });
  });

  it('case stub success',function (done) {
    // Define fake result.
    const fakeResult = 'test';
    // Stub the real fn function inside custom helper.
    const stubSuccess = sinon.stub(fwm,'fn');
    stubSuccess.callsFake(async function (input,exits) {
      // Setup your success result here.
      exits.success(fakeResult);
    });

    supertest(sails.hooks.http.app)
      .get('/hello')
      // Expect endpoint to output fake result.
      .expect(fakeResult)
      .end(function() {
        // Make sure stub get called once.
        expect(stubSuccess.calledOnce).to.equal(true);
        // Restore stub.
        stubSuccess.restore();
        done();
      });
  });
});

当我使用mocha运行它时：

$ npx mocha test/hello.test.js 

  Test
    ✓ normal case
error: Sending 500 ("Server Error") response: 
 Error: XXX
    at Object.<anonymous> ...
    ✓ case stub error
    ✓ case stub success

  3 passing (407ms)

$
sails.jssinonstubunit-testing