when setting goes wrong

application.controller.js

import Ember from 'ember';

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

application.template.hbs

<h1> when 'set'-ing goes wrong </h1>

<p>
Bar is a computed property based on foo.

<ol>
<li>click on 'set foo' & see the property change</li>
<li>click on 'set bar' & see the property change</li>
<li>click on 'set foo' again. notice that after setting the property, the computed property is now overwritten</li>
</ol>
</p>

{{my-component}}

my-component.component.js

import Ember from 'ember';

export default Ember.Component.extend({
  foo: 'original foo',
  bar: Ember.computed('foo', function() {
  	return this.get('foo') + 'computed';
  }),
  
  actions: {
    setBar: function() {
      this.set('bar', 'bar set');
    },
    
    setFoo: function() {
      this.set('foo', 'new foo'); 
    }
  }
});

my-component.template.hbs

<h2> bar reads: {{bar}} </h2>

<button {{action 'setBar'}}> set bar </button>

<button {{action 'setFoo'}}> set foo </button>

twiddle.json

{
  "version": "0.5.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.2.0/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember-template-compiler.js"
  }
}