Async promise loop

promiseLoop.js

var Promise = require('bluebird');
var _       = require('lodash');

function promiseA() {
  return Promise.resolve([1]);
}

function promiseB(prevResult) {
  prevResult.push(2)
  return Promise.resolve(prevResult);
}

function promiseC(prevResult) {
  prevResult.push(3)
  return Promise.resolve(prevResult);
}

function loopingPromise(prevResult) {
  var nextResult = prevResult;

  if (nextResult.length === 10) {
    return Promise.resolve(nextResult);
  }

  return new Promise(function(resolve, reject) {
    setTimeout(function() {
      nextResult.push(_.last(nextResult) + 1);
      resolve(nextResult);
    }, 10);
  }).then(loopingPromise);
};

promiseA()
.then(promiseB)
.then(promiseC)
.then(loopingPromise)
.then(function (result) {
  console.log(result);
})
.catch(function(err) {
  console.log('ERROR: ', err);
});

/*
 » node promiseloop.js
[ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 ]
*/