wip

index.js

@@ -84,18 +84,88 @@ module.exports = {
     }
   },
 
+  _shouldIncludeHelpers() {
+    let appOptions = (this.app && this.app.options) || {};
+    let customOptions = appOptions['ember-cli-babel'];
+
+    if (customOptions && 'includeExternalHelpers' in customOptions) {
+      return customOptions.includeExternalHelpers === true;
+    } else {
+      return false;
+    }
+  },
+
+  _importHelpers(app) {
+    let helpersPath = 'vendor/babel-helpers/babel-helpers.js';
+
+    if (this.import) {  // support for ember-cli >= 2.7
+      this.import(helpersPath, { prepend: true });
+    } else if (app.import) { // support ember-cli < 2.7
+      app.import(helpersPath, { prepend: true });
+    } else {
+      // eslint-disable-next-line no-console
+      console.warn('Please run: ember install ember-cli-import-polyfill');
+    }
+  },
+
+  _getHelperWhitelist() {
+    let appOptions = this._getAppOptions();
+    let customOptions = appOptions['ember-cli-babel'];
+
+    return customOptions && customOptions.externalHelperWhitelist;
+  }
+
+  _getHelperVersion() {
+    let appOptions = this._getAppOptions();
+    let customOptions = appOptions['ember-cli-babel'];
+
+    return customOptions && customOptions.externalHelperVersion;
+  }
+
+  _getHelpersPlugin() {
+    return [
+      [
+        require.resolve('@babel/plugin-external-helpers'),
+        {
+          helperVersion: this._getHelperVersion(),
+          whitelist: this._getHelperWhitelist()
+        }
+      ]
+    ]
+  },
+
   treeForVendor() {
-    if (!this._shouldIncludePolyfill()) { return; }
+    let trees = [];
 
-    const Funnel = require('broccoli-funnel');
-    const UnwatchedDir = require('broccoli-source').UnwatchedDir;
+    if (this._shouldIncludePolyfill()) {
+      const Funnel = require('broccoli-funnel');
+      const UnwatchedDir = require('broccoli-source').UnwatchedDir;
 
-    // Find babel-core's browser polyfill and use its directory as our vendor tree
-    let polyfillDir = path.dirname(require.resolve('@babel/polyfill/dist/polyfill'));
+      // Find babel-core's browser polyfill and use its directory as our vendor tree
+      let polyfillDir = path.dirname(require.resolve('@babel/polyfill/dist/polyfill'));
 
-    return new Funnel(new UnwatchedDir(polyfillDir), {
-      destDir: 'babel-polyfill'
-    });
+      let polyfillTree = new Funnel(new UnwatchedDir(polyfillDir), {
+        destDir: 'babel-polyfill'
+      });
+
+      trees.push(polyfillTree);
+    }
+
+    // Helpers are a global config, so only the root application should bother
+    // generating and including the file.
+    if (this.parent === this.app && this._shouldIncludeHelpers()) {
+      const babel = require('@babel/core');
+      const writeFile = require('broccoli-file-creator');
+
+      let helpers = babel.buildExternalHelpers(this._getHelperWhitelist);
+      let babelHelpersTree = writeFile('babel-helpers/babel-helpers.js', helpers);
+
+      trees.push(babelHelpersTree);
+    }
+
+    if (trees.length > 0) {
+      return new MergeTrees(trees);
+    }
   },
 
   included: function(app) {
@@ -105,6 +175,13 @@ module.exports = {
     if (this._shouldIncludePolyfill()) {
       this._importPolyfill(app);
     }
+
+
+    // Helpers are a global config, so only the root application should bother
+    // generating and including the file.
+    if (this.parent === app && this._shouldIncludeHelpers()) {
+      this._importHelpers(app);
+    }
   },
 
   isPluginRequired(pluginName) {
@@ -120,7 +197,11 @@ module.exports = {
   },
 
   _getAddonOptions() {
-    return (this.parent && this.parent.options) || (this.app && this.app.options) || {};
+    return (this.parent && this.parent.options) || this._getAppOptions();
+  },
+
+  _getAppOptions() {
+    return (this.app && this.app.options) || {};
   },
 
   _parentName() {
@@ -158,6 +239,7 @@ module.exports = {
   _getBabelOptions(config) {
     let addonProvidedConfig = this._getAddonProvidedConfig(config);
     let shouldCompileModules = this._shouldCompileModules(config);
+    let shouldIncludeHelpers = this._shouldIncludeHelpers();
 
     let emberCLIBabelConfig = config['ember-cli-babel'];
     let shouldRunPresetEnv = true;
@@ -188,6 +270,7 @@ module.exports = {
     let userPostTransformPlugins = addonProvidedConfig.postTransformPlugins;
 
     options.plugins = [].concat(
+      shouldIncludeHelpers ** this._getHelpersPlugin(),
       userPlugins,
       this._getDebugMacroPlugins(config),
       this._getEmberModulesAPIPolyfill(config),

package.json

@@ -39,6 +39,7 @@
   },
   "dependencies": {
     "@babel/core": "^7.0.0",
+    "@babel/plugin-external-helpers": "^7.0.0",
     "@babel/plugin-transform-modules-amd": "^7.0.0",
     "@babel/polyfill": "^7.0.0",
     "@babel/preset-env": "^7.0.0",
@@ -48,7 +49,9 @@
     "babel-plugin-module-resolver": "^3.1.1",
     "broccoli-babel-transpiler": "^7.1.0",
     "broccoli-debug": "^0.6.4",
+    "broccoli-file-creator": "^2.1.1",
     "broccoli-funnel": "^2.0.1",
+    "broccoli-merge-trees": "^3.0.1",
     "broccoli-source": "^1.1.0",
     "clone": "^2.1.2",
     "ember-cli-version-checker": "^2.1.2",

yarn.lock

@@ -193,6 +193,13 @@
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/@babel/parser/-/parser-7.0.0.tgz#697655183394facffb063437ddf52c0277698775"
 
+"@babel/plugin-external-helpers@^7.0.0":
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-external-helpers/-/plugin-external-helpers-7.0.0.tgz#61ee7ba5dba27d7cad72a13d46bec23c060b762e"
+  integrity sha512-tZKTMdhZvTy0KCEX5EGQQm1RHr7jUa36q/yax1baEA0yZapVYmu10yW7LTqijITgSq416gPVjrcexiA6y4pJlA==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+
 "@babel/plugin-proposal-async-generator-functions@^7.0.0":
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-async-generator-functions/-/plugin-proposal-async-generator-functions-7.0.0.tgz#5d1eb6b44fd388b97f964350007ab9da090b1d70"
@@ -1579,6 +1586,14 @@ broccoli-file-creator@^1.1.1:
     broccoli-plugin "^1.1.0"
     mkdirp "^0.5.1"
 
+broccoli-file-creator@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/broccoli-file-creator/-/broccoli-file-creator-2.1.1.tgz#7351dd2496c762cfce7736ce9b49e3fce0c7b7db"
+  integrity sha512-YpjOExWr92C5vhnK0kmD81kM7U09kdIRZk9w4ZDCDHuHXW+VE/x6AGEOQQW3loBQQ6Jk+k+TSm8dESy4uZsnjw==
+  dependencies:
+    broccoli-plugin "^1.1.0"
+    mkdirp "^0.5.1"
+
 broccoli-funnel-reducer@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/broccoli-funnel-reducer/-/broccoli-funnel-reducer-1.0.0.tgz#11365b2a785aec9b17972a36df87eef24c5cc0ea"
@@ -1666,6 +1681,14 @@ broccoli-merge-trees@^3.0.0:
     broccoli-plugin "^1.3.0"
     merge-trees "^2.0.0"
 
+broccoli-merge-trees@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/broccoli-merge-trees/-/broccoli-merge-trees-3.0.1.tgz#545dfe9f695cec43372b3ee7e63c7203713ea554"
+  integrity sha512-EFPBLbCoyCLdjJx0lxn+acWXK/GAZesXokS4OsF7HuB+WdnV76HVJPdfwp9TaXaUkrtb7eU+ymh9tY9wOGQjMQ==
+  dependencies:
+    broccoli-plugin "^1.3.0"
+    merge-trees "^2.0.0"
+
 broccoli-middleware@^1.2.1:
   version "1.2.1"
   resolved "https://registry.yarnpkg.com/broccoli-middleware/-/broccoli-middleware-1.2.1.tgz#a21f255f8bfe5a21c2f0fbf2417addd9d24c9436"