Awesome Macros Array Dependents

controllers.application.js

import Ember from 'ember';
import { array } from 'ember-awesome-macros';
import computed from 'ember-macro-helpers/computed';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  array: [{ someProp: 1 }],
  prop: 'someProp',
  
  mappedArray: computed(array.mapBy('array', 'prop'), (array) => array),
  
  init() {
   	this._super(...arguments);
    this.set('dependents', this.mappedArray._dependentKeys.join(', '));
  },
  
  actions: {
   addItem() {
  	this.get('array').pushObject({ someProp: 1 }); 
   }
  }
});

templates.application.hbs

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

array.mapBy Dependents: {{dependents}}
<br>
<br>
array: {{array.length}}
<br>
mappedArray: {{mappedArray.length}}
<br>
<br>

<button {{action 'addItem'}}>Add Item</button>

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1",
    "ember-awesome-macros": "0.36.0",
    "ember-macro-helpers": "0.14.1"
  }
}