Repro example for needing to Polyfill Date/Number prototypes in node.

intl-node-protoype-example.js

var express = require('express');
var app = express();

if (global.Intl) {
    // `Intl` exists, but it doesn't have the data we need, so load the
    // polyfill and patch the constructors we need with the polyfill's.
    var IntlPolyfill    = require('intl');
    Intl.NumberFormat   = IntlPolyfill.NumberFormat;
    Intl.DateTimeFormat = IntlPolyfill.DateTimeFormat;

    // HERE, Date/Number prototypes still seem to need polyfilled (node@4.2.1, node@5.8.0).
    IntlPolyfill.__applyLocaleSensitivePrototypes();
} else {
    // No `Intl`, so use and load the polyfill.
    global.Intl = require('intl');

    // HERE, Even when replacing Intl with the polyfill,
    // the the prototypes need polyfilled.
    global.Intl.__applyLocaleSensitivePrototypes();
}

app.get('/', function (req, res) {
  var date = new Date();
  var options = {
      weekday: 'long',
      year: 'numeric',
      month: 'long',
      day: 'numeric'
  };
  var ar = date.toLocaleDateString('ar', options);
  var gb = date.toLocaleDateString('en-GB', options);
  res.send('ar: ' + ar + ' gb: ' + gb);
});

app.listen(3000, function () {
  console.log('Example app listening on port 3000!');
});