EmberInflector

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle',
  plural: Ember.computed(function() { 
      return Ember.Inflector.inflector.pluralize("gas"); 
  }),
  singular: Ember.computed(function() { 
      return Ember.Inflector.inflector.singularize("gases"); 
  }), 
});

application.template.hbs

<h1>Ember-Inflector Bug</h1>
<br>
<br>

<h2> Pluralizing Gas </h2>
{{plural}} 
<br>
<h2> Singularizing Gases </h2>
{{singular}}

twiddle.json

{
  "version": "0.4.13",
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.1.0/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.1.0/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.1.0/ember-template-compiler.js"
  }
}