🐒 Better promise.series simple implementation ! It now gives the result array.

jojoPromiseSeriesV2.js

'use strict';

Promise.series = promises =>
  ((results = []) =>
    promises
      .reduce(
        (promise, current) => promise
          .then(current)
          .then(function () {
            results.push(arguments);
            return results
          }),
        Promise.resolve()
      ))();