Promise rejection

controllers.application.js

import Ember from 'ember';
import RSVP from 'rsvp';
import computed from 'ember-computed';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  _deferStuff: computed(() => RSVP.defer()),
  awaitStuff: computed.readOnly('_deferStuff.promise'),
  setup() {
    this.get('awaitStuff').then(() => {
      this.set('message', 'Stuff was done');
    });
    this.get('awaitStuff').catch(() => {
      this.set('message', 'Stuff was cancelled');
    });
  },

  actions: {
    setup() {
      this.setup();
    },
    resolve() {
      this.get('_deferStuff').resolve();
    },
    reject() {
      this.get('_deferStuff').reject();
    },
    reset() {
      this.setProperties({
        _deferStuff: RSVP.defer(),
        message: '',
      });
    },
  }
});

templates.application.hbs

<h1>Ember catches rejected promise</h1>

<p>Even if we handle rejection?</p>

<a href="#" {{action 'setup'}}>Setup</a>
<a href="#" {{action 'resolve'}}>Resolve</a>
<a href="#" {{action 'reject'}}>Reject</a>
<a href="#" {{action 'reset'}}>Reset</a>


<p>{{message}}</p> 

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"
  }
}