how to refactor it ?

promise

var request = [
            profileUtil.createUser('[email protected]', 'qwer1234', 'test', 'Company'),
            profileUtil.createUser('[email protected]', 'qwer1234', 'test2', 'Company'),
        ];

        request[0].then(function(value) {
                return request[1];
            })
            .then(function(value) {
                return request[2];
            })
            .then(function  (value) {
                done();
            })
            .catch(function(reason) {
                console.log(reason);
                // (reason.errmsg).should.include('duplica2te');
                done();
            });

其實他已經是對的了，只是他在request宣告時就開始執行了

ok('1') 這時候就已經執行了

所以這case可以改成下面這樣，就能一個接著一個做

function job(code){
    return new Promise(function(resolve, reject){
        setTimeout(function(){
            console.log(code);
            if(code >=0){
                resolve(code);
            }else{
                reject(code);
            }
        },1000);
    });
}

function done(){
    console.log('done');
}

var request = [1, 2, -1, 3];

var promise = Promise.resolve('start');

for(var i=0; i<request.length; i++) {
    function exec(i) {
        promise = promise.then(function(value){
            console.log('value', value, i);

            return job(i);
        });
    }
    exec(i);
}
//all resolved
promise.then(function  (value) {
    console.log('value', value);
    done();
})
.catch(function(error) {
    console.log('err', error);
    // (error.errmsg).should.include('duplica2te');
    done();
});

或是把job包成function 需要的時候再執行()

function ok(msg){
    return function(){
        return new Promise(function(resolve, reject){
            setTimeout(function(){
                console.log(msg);
                resolve(msg);
            },1000);
        });
    }
}

function fail(msg){
    return function(){
        return new Promise(function(resolve, reject){
            setTimeout(function() {
                console.log(msg);
                reject(new Error('err'));
            },1000);
        });
    }
}

function done(){
    console.log('done');
}    

var jobs = [ok('1'), ok('2'), fail('123'), ok('3')];

var promise = Promise.resolve('start');

for(var i=0; i<jobs.length; i++) {
    function exec(i) {
        promise = promise.then(function(value){
            console.log('value', value, i);
            //start exec here
            return jobs[i]();
        });
    }
    exec(i);
}
//all resolved
promise.then(function  (value) {
    console.log('value', value);
    done();
})
.catch(function(error) {
    console.log('err', error);
    // (error.errmsg).should.include('duplica2te');
    done();
});

By the way,

如果for loop那邊用的i是用let宣告的(不是var)，應該就不會有這問題了

node要用es6語法的話，開頭加'use strict'
就可以用const, let宣告，可以避免很多var常見的陷阱(hoisting)

另外也支援這樣的匿名function

//1 原本宣告方法
let f1 = function(arg1,arg2) {
    return arg1+arg2;
}
//2 單行，不用return跟分號
let f2 = (arg1, arg2)=> arg1+arg2

//3 多行，要自己加return
let f3 = (arg1, arg2)=> {
    return arg1+arg2;
}

/* 
其他還有一些list的operation
像是filter, map
 */
let arr = [1,2,3];
//[2,4,6]
console.log(arr.map(value=>value*2));
//[2,3]
console.log(arr.filter(value=>value>=2));
//[1,2,3]
console.log(arr);