New Twiddle

components.component-handles-own-actions.js

import Ember from 'ember';

export default Ember.Component.extend({
  init(){
    this._super(...arguments);
    this.name = 'foo';
  },
  actions: {
    toggleName(){
      this.set('name', this.name === 'foo' ? 'bar' : 'foo') 
    }
  }
});

components.one-way-bound.js

import Ember from 'ember';

export default Ember.Component.extend({
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  actions: {
    toggleCaps(){
      if(isUpperCase(this.get('model'))){
        this.set('model', this.get('model').toLowerCase());
      }else{
        this.set('model', this.get('model').toUpperCase());
      }
    }
  }
});


function isUpperCase(str) {
    return str === str.toUpperCase();
}

routes.application.js

import Ember from 'ember';

export default Ember.Route.extend({
  model(){
    return "I am a model"; 
  },
  setupController(controller, model){
    controller.set('model', "Something other than what the model hook returned");
    controller.set('whatTheModelHookReturned', model);
  }
});

templates.application.hbs

{{one-way-bound passedData=model onButtonPress=(action 'toggleCaps')}}

templates.components.component-handles-own-actions.hbs

<button {{action 'toggleName'}}>{{name}}</button>

templates.components.one-way-bound.hbs

{{passedData}} 
<button {{action onButtonPress}}>Toggle caps</button>

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}