local-storage.js/lib/localStorage.js

// http://www.rajdeepd.com/articles/chrome/localstrg/LocalStorageSample.htm

// NOTE:
// this varies from actual localStorage in some subtle ways

// also, there is no persistence
// TODO persist
(function () {
  "use strict";

  var db;

  function LocalStorage() {
  }
  db = LocalStorage;

  db.prototype.getItem = function (key) {
    if (this.hasOwnProperty(key)) {
      return String(this[key]);
    }
    return null;
  };

  db.prototype.setItem = function (key, val) {
    this[key] = String(val);
  };

  db.prototype.removeItem = function (key) {
    delete this[key];
  };

  db.prototype.clear = function () {
    var self = this;
    Object.keys(self).forEach(function (key) {
      self[key] = undefined;
      delete self[key];
    });
  };

  db.prototype.key = function (i) {
    i = i || 0;
    return Object.keys(this)[i];
  };

  db.prototype.__defineGetter__('length', function () {
    return Object.keys(this).length;
  });

  if (global.localStorage) {
    module.exports = localStorage;
  } else {
    module.exports = new LocalStorage();
  }
}());