text: var foo = 123;
  var bar = foo.toString();
  var test = window;
  window.helloWorld = function () { return console.log('hello world'); };
  window.helloWorld();
  Math.seedrandom();
  Date.parse;
  String.prototype.endsWith = function (suffix) {
      var str = this;
      return str && str.indexOf(suffix, str.length - suffix.length) !== -1;
  };
  console.log('foo bar'.endsWith('bas'));
  console.log('foo bas'.endsWith('bas'));
  