New Twiddle

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  publishable: true,
  
  actions: {
  	publish() {
    	console.log('publish');
    }
  }
});

application.template.hbs

<button {{action (if publishable 'publish' (action (mut undefProp)))}}>Publish</button>
<br>
<br>

twiddle.json

{
  "version": "0.4.16",
  "EmberENV": {
    "FEATURES": {}
  },
  "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"
  }
}