Overriding CP

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  firstName: 'John',
  lastName: 'Doe',
  fullName: Ember.computed('firstName', 'lastName', {
    get() {
      return `${this.get('firstName')} ${this.get('lastName')}`.trim()
    },
    /*set(prop, value) {
      return `[setter: ${value}!]`
    }*/
  })
});

controllers.application.js

import Ember from 'ember';

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

templates.application.hbs

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

{{my-component fullName="Overridden Fullname"}}

templates.components.my-component.hbs

<p>Hello {{fullName}}</p>

twiddle.json

{
  "version": "0.13.1",
  "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": "2.16.3"
  }
}