slow promise testing

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  text: 'nothing',
  
  p1() {
    return new Ember.RSVP.Promise((resolve, reject) => {
      let delay = 10; // <= 10 passes, > 10 fails
      // doesn't matter if you resolve or rejectt
      setTimeout(resolve, delay);    
    });
  },

  p2() {
    return this.p1().then(() => {
      console.log('shouldnt go here');
    }, () => {
      console.log('rejected');
      return 2;
    });
  },
  p3() {
    return this.p2().then(() => {
      this.set('text', 'clicked');
    });
  },

  actions: {
    click() {
      this.p3();
    }
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
<button {{action "click"}}>click me</button>
<p>{{text}}</p>
<br>
<br>

tests.acceptance.my-acceptance-test.js

import { test } from 'qunit';
import moduleForAcceptance from '../../tests/helpers/module-for-acceptance';

moduleForAcceptance('TODO: put something here');

test('visiting /my-acceptance', function(assert) {
  assert.expect(1);
  visit('/');
  click('button')
  andThen(function() {
    assert.equal(find('p:contains(clicked)').length, 1, 'clicked found');
  });
});

tests.helpers.destroy-app.js

import Ember from 'ember';

export default function destroyApp(application) {
  Ember.run(application, 'destroy');
}

tests.helpers.module-for-acceptance.js

import { module } from 'qunit';
import startApp from '../helpers/start-app';
import destroyApp from '../helpers/destroy-app';

export default function(name, options = {}) {
  module(name, {
    beforeEach() {
      this.application = startApp();

      if (options.beforeEach) {
        options.beforeEach.apply(this, arguments);
      }
    },

    afterEach() {
      if (options.afterEach) {
        options.afterEach.apply(this, arguments);
      }

      destroyApp(this.application);
    }
  });
}

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.helpers.start-app.js

import Ember from 'ember';
import Application from '../../app';
import config from '../../config/environment';

export default function startApp(attrs) {
  let application;

  let attributes = Ember.merge({rootElement: "#test-root"}, config.APP);
  attributes = Ember.merge(attributes, attrs); // use defaults, but you can override;

  Ember.run(() => {
    application = Application.create(attributes);
    application.setupForTesting();
    application.injectTestHelpers();
  });

  return application;
}

tests.test-helper.js

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

setResolver(resolver);

twiddle.json

{
  "version": "0.7.2",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": true
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.4.4/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.4.3/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.4.4/ember-template-compiler.js"
  }
}