getLastResolvedPromise

example.js

import getLastResolvedPromise from './getLastResolvedPromise'

const promise1 = Promise.resolve(3);
const promise2 = new Promise(function(resolve, reject) {
  setTimeout(resolve, 200, 'foo');
});
const promise3 = new Promise(function(resolve, reject) {
  setTimeout(resolve, 100, 'bar');
});

getLastResolvedPromise([promise1, promise2, promise3]).then(function(lastResult) {
  console.log('lastResult', lastResult);
});

getLastResolvedPromise.js

let lastResult

const withSaveResult = promise => (
 promise.then(result => { 
  lastResult = result 
 })
)

const getLastResolvedPromise = promises => {
 lastResult = null
 return Promise.all(promises.map(withSaveResult)).then(() => lastResult)
}

export default getLastResolvedPromise