async computed property experiment

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle'
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>

models.child.js

import DS from 'ember-data';

export default DS.Model.extend({
  firstName: DS.attr(),
  lastName: DS.attr(),
  
  parent: DS.belongsTo('parent', { async: true }),
  
  fullName: Ember.computed('firstName', 'lastName', function() {
    var firstName = this.get('firstName');
    var lastName = this.get('lastName');
    
    return firstName + lastName;
  })
});

models.parent.js

import DS from 'ember-data';

export default DS.Model.extend({
  child: DS.belongsTo('child', { async: true })
});

twiddle.json

{
  "version": "0.4.11",
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "pretender": "https://rawgit.com/pretenderjs/pretender/master/pretender.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.9/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/1.13.11/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.9/ember-template-compiler.js"
  }
}