unit-testing - Sails.js:无法为单元测试目的 stub 帮助程序

Question

节点版本 : v12.18.3
帆版 (帆):1.2.3

执行单元测试时，我无法 stub sails helper。我有一个助手来处理与数据库的所有通信。此外，我有一个 API，它使用这个助手。在我的测试中，我试图使用 sinon 来 stub 助手:
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()
            }
      })
})

当我运行测试时，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 stub helper ？

Answer 1

风帆助手使用 machine ，这使得 stub 制作更加棘手。
AFAIK ，stubsails helpers 的替代方法是通过stubbing 真正的 fn 函数，因为机器会调用助手的 fn 函数。
更新 : 更改使用 supertest 的示例。
例如:

我使用 HelloController 创建端点 GET/hello，

我使用来自 helper's example 的助手格式欢迎信息,

我为端点 GET/hello 创建了测试规范。

我使用 mocha 运行它而不使用 Lifecycle.js，但将生命周期嵌入到测试规范 ( 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);
  }
};

并且不要忘记添加路由: 'GET /hello': 'HelloController.hello'在 config/routes.js。
测试规范包含 3 种情况(正常调用、 stub 错误和 stub 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)

$