File Chooser Tests Working Ember 2.5.1

components.file-chooser.js

import Ember from 'ember';

// this doesn't work in Ember Twiddle
// import { testing } = Ember;

export default Ember.Component.extend({
  actions: {
    filesSelected(event) {
      // this doesn't work in Ember Twiddle
      // const files = testing ? event.testingFiles : event.target.files;
      const files = event.testingFiles;
      if (files.length === 0) {
        Ember.Logger.log('you must add a file');
      } else if (files.length > 0) {
        this.sendAction('action', files);
      }
    }
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  firstFile: null,
  
  actions: {
    addFiles(files) {
     	this.set('firstFile', files[0].name); 
    }
  }
});

templates.application.hbs

{{file-chooser action="addFiles"}}
<br>
<p>first file: <span id="first-file-text">{{firstFile}}</span></p>

templates.components.file-chooser.hbs

<input type="file" id="file-chooser" onchange={{action "filesSelected"}}>
<label for="file-chooser" >choose file</label>

tests.acceptance.file-chooser-test.js

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

moduleForAcceptance('Acceptance: File Upload');

test('upload file', function(assert) {
  visit('/');
  uploadFile('#file-chooser', ['test text'], {});

  andThen(function() {
    assert.equal(currentURL(), '/');
    assert.equal(find('#first-file-text').text(), 'test.txt', {});
  });
});

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 Ember from 'ember';
import startApp from '../helpers/start-app';
import destroyApp from '../helpers/destroy-app';

const { RSVP: { Promise } } = Ember;

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

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

    afterEach() {
      let afterEach = options.afterEach && options.afterEach.apply(this, arguments);
      return Promise.resolve(afterEach).then(() => 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';

import uploadFile from './utils/upload-file';

const { run } = Ember;
const assign = Ember.assign || Ember.merge;

export default function startApp(attrs) {
  let application;

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

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

  return application;
}

tests.helpers.utils.upload-file.js

/* global Blob */

import Ember from 'ember';

function createFile(content = ['test'], options = {}) {
  const {
    name,
    type
  } = options;

  const file = new Blob(content, {type : type ? type : 'text/plain'});
  file.name = name ? name : 'test.txt';

  return file;
}


export default Ember.Test.registerAsyncHelper('uploadFile', function(app, selector, content, options) {
  const file = createFile(content, options);

  return triggerEvent(
    selector,
    'change',
    { testingFiles: [file] }
  );
});

tests.test-helper.js

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

setResolver(resolver);

twiddle.json

{
  "version": "0.8.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": true
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.5.1",
    "ember-template-compiler": "2.5.1"
  }
}