sniffs for global variables

globalsniffer.js

/**
 * Detect Globals
 * @source https://github.com/sindresorhus/log-globals
 */

(function () {
  'use strict';

  function getIframe() {
    var el = document.createElement('iframe');
    el.style.display = 'none';
    document.body.appendChild(el);
    var win = el.contentWindow;
    document.body.removeChild(el);
    return win;
  }

  function detectGlobals() {
    var iframe = getIframe();
    var globals = Object.create(null);
    for (var prop in window) {
      if (!(prop in iframe)) {
        globals[prop] = window[prop];
      }
    }
    return globals;
  }

  console.log(detectGlobals());
})();