New Twiddle

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  actions: {
    clicked() {
      this.$().append("Clicked");
    }
  }
});

components.my-sub-component.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'
});

templates.application.hbs

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

{{my-component}}

templates.components.my-component.hbs

{{my-sub-component clicked=(action 'clicked')}}

templates.components.my-sub-component.hbs

<button {{action clicked}}>Click me</button>

tests.helpers.resolver.js

import Resolver from '../../resolver';
import config from '../../config/environment';

const resolver = Resolver.create();

resolver.namespace = {
  modulePrefix: config.modulePrefix,
  podModulePrefix: config.podModulePrefix
};

export default resolver;

tests.integration.components.my-component-test.js

import { moduleForComponent, test } from 'ember-qunit';
import hbs from 'htmlbars-inline-precompile';

moduleForComponent('my-component', 'three different ways to test component actions in a component integration test', {
  integration: true
});

test('it interacts with the action thru the real my-sub-component', function(assert) {
  this.render(hbs`{{my-component}}`);
  assert.equal(this.$().text().trim(), 'Click me');

  this.$("button").click();

  // "Clicked" comes from the action defined in
  // components/my-component.js
  assert.equal(this.$().text().trim(), 'Click meClicked');

  this.$("button").click();
  assert.equal(this.$().text().trim(), 'Click meClickedClicked');  
});

test('it uses fake a fake component and template to create a simplified DOM element we can interact with', function(assert) {

  // Override component and template for this test specifically
  // This may work well if you want to "stub" out nested components
  // because they are overly complex
  this.register('component:my-sub-component', Ember.Component.extend());
  this.register('template:components/my-sub-component',  
      hbs`<div {{action clicked}}>Click me</div>`
   );

  this.render(hbs`{{my-component}}`);
  assert.equal(this.$().text().trim(), 'Click me');

  // The 'div' here shows us that we are not rendering the
  // button in templates/components/my-sub-component.hbs but
  // instead using the div defined a few lines up in this test.
  this.$("div").click();

  // "Clicked" is still coming from the action defined in
  // components/my-component.js
  assert.equal(this.$().text().trim(), 'Click meClicked');

  this.$("div").click();
  assert.equal(this.$().text().trim(), 'Click meClickedClicked'); 
});


// 
//  This is my  favorite of all of the approaches listed.
// 
test('it tests an action by defining the action in the test and calling the action directly', function(assert) {
  let clicked = () => { this.$().append("WAT"); };
  this.set('actions.clicked', clicked);
  this.render(hbs`{{my-component clicked=(action 'clicked')}}`);
  assert.equal(this.$().text().trim(), 'Click me');
  
  clicked();

  // The term WAT shows that we are defining the action
  // a few lines up in this test. Even though the real 
  // my-sub-component is used this shows that we are using
  //  the action defined  in the test.
  assert.equal(this.$().text().trim(), 'Click meWAT');

  clicked();
  assert.equal(this.$().text().trim(), 'Click meWATWAT');  
});

tests.test-helper.js

import resolver from './helpers/resolver';
import {
  setResolver
} from 'ember-qunit';

setResolver(resolver);

twiddle.json

{
  "version": "0.11.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": true
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.11.0",
    "ember-data": "2.11.0",
    "ember-template-compiler": "2.11.0",
    "ember-testing": "2.11.0"
  },
  "addons": {}
}