fixes addon on apps with engines

index.js

@@ -3,42 +3,60 @@
 
 const path = require('path');
 const Funnel = require('broccoli-funnel');
-const MergeTrees = require('broccoli-merge-trees');
-const map = require('broccoli-stew').map;
+const BroccoliMergeTrees = require('broccoli-merge-trees');
+const fastbootTransform = require('fastboot-transform');
+const resolve = require('resolve');
 
 module.exports = {
   name: require('./package').name,
 
-  included(app) {
+  included() {
     this._super.included.apply(this, arguments);
+    let app;
 
-    // see: https://github.com/ember-cli/ember-cli/issues/3718
-    while (typeof app.import !== 'function' && app.app) {
-      app = app.app;
+    // If the addon has the _findHost() method (in ember-cli >= 2.7.0), we'll just
+    // use that.
+    if (typeof this._findHost === 'function') {
+      app = this._findHost();
+    } else {
+      // Otherwise, we'll use this implementation borrowed from the _findHost()
+      // method in ember-cli.
+      let current = this;
+      do {
+        app = current.app || app;
+      } while (current.parent.parent && (current = current.parent));
     }
 
-    if (typeof app.import !== 'function') {
-      throw new Error('ember-hammertime is being used within another addon or engine '
-       + 'and is having trouble registering itself to the parent application.');
-    }
-
-    app.import('vendor/hammer-time.js');
+    app.import('vendor/hammer-timejs/hammer-time.js');
   },
 
-  treeForVendor(vendorTree) {
+  treeForVendor(tree) {
     let trees = [];
-    let hammertimeTree = new Funnel(path.dirname(require.resolve('hammer-timejs/hammer-time.js')), {
-      files: ['hammer-time.js']
-    });
-    hammertimeTree = map(hammertimeTree, (content) => `if (typeof FastBoot === 'undefined') { ${content} }`);
 
-    if (vendorTree !== undefined) {
-      trees.push(vendorTree);
+    let hammerTimeJs = fastbootTransform(new Funnel(this.pathBase('hammer-timejs'), {
+      files: ['hammer-time.js'],
+      destDir: 'hammer-timejs'
+    }));
+
+    trees.push(hammerTimeJs);
+
+    if (tree) {
+      trees.push(tree);
     }
 
-    trees.push(hammertimeTree);
+    return new BroccoliMergeTrees(trees);
+  },
 
-    return new MergeTrees(trees);
+  /*
+    Rely on the `resolve` package to mimic node's resolve algorithm.
+    It finds the modules in a manner that works for npm 2.x,
+    3.x, and yarn in both the addon itself and projects that depend on this addon.
+    This is an edge case b/c some modules do not have a main
+    module we can require.resolve through node itself and similarily ember-cli
+    does not have such a hack for the same reason.
+  */
+  pathBase(packageName) {
+    return path.dirname(resolve.sync(`${packageName}/package.json`, { basedir: __dirname }));
   },
 
   isDevelopingAddon() {

package.json

@@ -27,12 +27,14 @@
     "test:all": "ember try:each"
   },
   "dependencies": {
-    "broccoli-funnel": "^2.0.1",
-    "broccoli-merge-trees": "^3.0.1",
+    "broccoli-funnel": "^2.0.2",
+    "broccoli-merge-trees": "^3.0.2",
     "broccoli-stew": "^2.0.0",
     "ember-cli-babel": "^6.16.0",
     "ember-get-config": "^0.2.4",
-    "hammer-timejs": "^1.1.0"
+    "fastboot-transform": "^0.1.3",
+    "hammer-timejs": "^1.1.0",
+    "resolve": "^1.10.0"
   },
   "devDependencies": {
     "@ember/optional-features": "^0.6.3",