index.js

/* jshint node: true */
'use strict';

var path = require('path');
var mergeTrees = require('broccoli-merge-trees');
var babel = require('broccoli-babel-transpiler');
var lodashPlugin = require('babel-plugin-lodash');

module.exports = {
  name: 'lodash',

  setupPreprocessorRegistry: function(type, registry) {
    var addon = this;

    registry.add('js', {
      name: 'ember-lodash',
      ext: 'js',
      toTree: function(tree) {
        return babel(tree, { plugins: [ lodashPlugin ] });
      }
    });
  },

  treeForAddon: function(tree) {
    var lodashPath = path.dirname(require.resolve('lodash-es/lodash.js'));
    var lodashTree = this.treeGenerator(lodashPath);

    var trees = mergeTrees([lodashTree, tree], {
      overwrite: true
    });

    return this._super.treeForAddon.call(this, trees);
  }
};