Working Ember 2.4.3

file-chooser.js

import Ember from 'ember';

const {
  run: {
    bind
  }
} = Ember;

export default Ember.Component.extend({
  label: 'choose a file',

  didInsertElement() {
    this.$().on('change', bind(this,'filesSelected'));
  },

  willDestroyElement() {
    this.$().off('change', bind(this,'filesSelected'));   
  },

  filesSelected(event) {
    const files = event.target.files;
    if (files.length === 0) {
      Ember.Logger.log('you must add a file');
    } else if (files.length > 0) {
      this.sendAction('action', files);
    }
  }
});

file-upload-helper.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',
    { target: { files: [file] } }
  );
});