gistfile1.js

var assert = require('assert');

var a = {
  get a() {
    return "a";
  }
};
assert.deepEqual(Object.keys(a), ['a'], 'es6 enhanced object literals');

var b = {};
Object.defineProperty(b, 'b', {
  get: function() {
    return 'b';
  },
  enumerable: true
});
assert.deepEqual(Object.keys(b), ['b'], 'ES5 getter');

var c = {};
Object.defineProperty(c, 'c', {
  get: function() {
    return 'c';
  },
  set: function(c) {
    // lol don't care;
  },
  enumerable: true
});
assert.deepEqual(Object.keys(c), ['c'], 'ES5 getter/setter (setters shouldn\'t change anything)');

var d = {_d:'_d'};
Object.defineProperty(d, 'd', {
  get: function() {
    return this._d;
  },
  set: function(d) {
    this._d = d;
  },
  enumerable: true
});
assert.deepEqual(Object.keys(d), ['_d', 'd'], 'ES5 silly proxy/getter of a property');

var e = {};
Object.defineProperties(e, {
  '_e': { value: 'e', writable: true },
  'e': {
    get: function() { return this._e; },
    set: function(e) { this._e = e; },
    enumerable: true
  }
});
assert.deepEqual(Object.keys(e), ['e'], 'defineProperties works the same as defineProperty, right?');

function F() { }
Object.defineProperties(F.prototype, {
  '_f': { value: 'f', writable: true },
  'f': {
    get: function() { return this._f; },
    set: function(f) { this._f = f; },
    enumerable: true
  }
});
var f = new F();
assert.deepEqual(Object.keys(f), [], 'prototype properties aren\'t inherited... why the fuck not?');

function G() {
  Object.defineProperties(this, {
    '_g': { value: 'g', writable: true },
    'g': {
      get: function() { return this._g; },
      set: function(g) { this._g = g; },
      enumerable: true
    }
  });
}
var g = new G();
assert.deepEqual(Object.keys(g), ['g'], 'at least this works...');