index.js

/* jshint node: true */
'use strict';
var path = require('path');
var mergeTrees = require('broccoli-merge-trees');
var VersionChecker = require('ember-cli-version-checker');

module.exports = {
  name: 'ember-leaflet',
  included: function(app) {
   //import javascript
   app.import(app.bowerDirectory + '/leaflet/dist/leaflet-src.js');

   app.import(app.bowerDirectory + '/leaflet/dist/leaflet.css');

   var imagesDestDir = '/assets/images';
   app.import(app.bowerDirectory + '/leaflet/dist/images/layers-2x.png', { destDir: imagesDestDir });
   app.import(app.bowerDirectory + '/leaflet/dist/images/layers.png', { destDir: imagesDestDir });
   app.import(app.bowerDirectory + '/leaflet/dist/images/marker-icon-2x.png', { destDir: imagesDestDir });
   app.import(app.bowerDirectory + '/leaflet/dist/images/marker-icon.png', { destDir: imagesDestDir });
   app.import(app.bowerDirectory + '/leaflet/dist/images/marker-shadow.png', { destDir: imagesDestDir });
 },

 treeForAddonTemplates: function treeForAddonTemplates (tree) {
    var checker = new VersionChecker(this);
    var dep = checker.for('ember', 'bower');

    var baseTemplatesPath = path.join(this.root, 'addon/templates');

    if (dep.lt('2.3.0-beta.1')) {
      var current = this.treeGenerator(path.join(baseTemplatesPath, 'current'))
      var specificVersionTemplate = this.treeGenerator(path.join(baseTemplatesPath, 'lt-2-3'));
      return mergeTrees([current, specificVersionTemplate], { overwrite: true })
    } else {
      return this.treeGenerator(path.join(baseTemplatesPath, 'current'));
    }
  }
};