javascript - 如何正确 stub 作为另一个 Promise 一部分的 Promise 对象

Question

我有一个 Promise 函数，它根据客户端 cookie 执行身份验证

const getInitialState = (id_token) => {
  let initialState;
  return new Promise((resolve,reject) => {
    if(id_token == null){
      initialState = {userDetails:{username: 'Anonymous',isAuthenticated: false}}
      resolve(initialState)
    }else{
        var decoded = jwt.verify(JSON.parse(id_token),'rush2112')
        db.one('SELECT  * FROM account WHERE account_id = $1',decoded.account_id)
          .then(function(result){
            console.log('result is : ',result)
            initialState = {userDetails:{username:result.username,isAuthenticated:true}}
            resolve(initialState)
          })
          .catch(function(err){
            console.log('There was something wrong with the token',e)
            reject('There was an error parsing the token')
          })
    }
  })
}

getInitialState 是一个 Promise 对象，如果 cookie 有效，它会调用数据库函数(另一个 Promise 对象)。

我想在此处 stub 数据库调用以解析为用户名。但无论我怎么尝试它都不起作用

我尝试了两个库sinonStubPromise和sinon-as-promised。但两者似乎都会导致超时错误，这告诉我 db 函数没有得到解决

我相信我没有正确地 stub 数据库函数

这些是我尝试过的各种方法

stub2 = sinon.stub(db,'one')

stub2.returnsPromise().resolves({username:'Kannaj'})

或

sinon.stub(db,'one').returns({username:'Kannaj'})

或

sinon.stub(db,'one')
         .withArgs('SELECT  * FROM account WHERE account_id = $1',1)
         .returns({username:'Kannnaj'})

或

let db = sinon.stub(db).withArgs('SELECT  * FROM account WHERE account_id = $1',1).returns({username:'Kannnaj'})

所有这些都会导致 Mocha 超时错误

Error: timeout of 2000ms exceeded. Ensure the done() callback is being called in this test.

这是我的整个测试函数

  it('should return a valid user if id_token is valid',function(){
    id_token = '{"account_id":1}'
    console.log('stub1: ',stub1(), typeof(stub1))
    console.log('stub2 : ',stub2,typeof(stub2))

    // my attempts here
    return expect(getInitialState(id_token)).to.eventually.be.true
  })

出于某种原因，我相信 mocha/sinon 一旦调用 db.any 就会失去 pg-promise 上下文。不知道为什么。

Answer 1

我无法与 sinon-as-promised 或 sinonStubPromise 交谈，但你不需要它们来完成这样的事情。

const sinon = require('sinon');
const chai = require('chai');
chai.use(require('chai-as-promised'));
const expect = chai.expect;

// real object
const db = {
  one: function () {
    // dummy function
  }
};

// real function under test
function foo () {
  return db.one('SELECT * FROM account WHERE account_id = $1');
}

describe('foo', function () {
  beforeEach(function () {
    sinon.stub(db, 'one')
      .withArgs('SELECT * FROM account WHERE account_id = $1')
      .returns(Promise.resolve({username: 'Kannaj'}));
  });

  it('should not timeout', function () {
    return expect(foo())
      .to
      .eventually
      .eql({username: 'Kannaj'});
  });

  afterEach(function () {
    db.one.restore();
  });
});