add ES2015 support

.jscsrc

@@ -1,4 +1,5 @@
 {
+  "esnext": true,
   "preset": "google",
   "disallowSpacesInAnonymousFunctionExpression": null,
   "excludeFiles": ["node_modules/**"]

.jshintrc

@@ -1,4 +1,5 @@
 {
+  "esnext": true,
   "node": true,
   "browser": true,
   "bitwise": true,

gulpfile.js

@@ -58,6 +58,17 @@ gulp.task('elements', function () {
   return styleTask('elements', ['**/*.css']);
 });
 
+// Transpile all JS to ES5.
+gulp.task('js', function () {
+  return gulp.src(['app/**/*.{js,html}'])
+    .pipe($.sourcemaps.init())
+    .pipe($.if('*.html', $.crisper())) // Extract JS from .html files
+    .pipe($.if('*.js', $.babel()))
+    .pipe($.sourcemaps.write('.'))
+    .pipe(gulp.dest('.tmp/'))
+    .pipe(gulp.dest('dist/'));
+});
+
 // Lint JavaScript
 gulp.task('jshint', function () {
   return gulp.src([
@@ -123,7 +134,7 @@ gulp.task('fonts', function () {
 
 // Scan your HTML for assets & optimize them
 gulp.task('html', function () {
-  var assets = $.useref.assets({searchPath: ['.tmp', 'app', 'dist']});
+  var assets = $.useref.assets({searchPath: ['.tmp', 'dist']});
 
   return gulp.src(['app/**/*.html', '!app/{elements,test}/**/*.html'])
     // Replace path for vulcanized assets
@@ -233,7 +244,7 @@ gulp.task('serve', ['styles', 'elements', 'images'], function () {
   gulp.watch(['app/**/*.html'], reload);
   gulp.watch(['app/styles/**/*.css'], ['styles', reload]);
   gulp.watch(['app/elements/**/*.css'], ['elements', reload]);
-  gulp.watch(['app/{scripts,elements}/**/{*.js,*.html}'], ['jshint']);
+  gulp.watch(['app/{scripts,elements}/**/{*.js,*.html}'], ['jshint','js']);
   gulp.watch(['app/images/**/*'], reload);
 });
 
@@ -265,7 +276,7 @@ gulp.task('default', ['clean'], function (cb) {
   // Uncomment 'cache-config' after 'rename-index' if you are going to use service workers.
   runSequence(
     ['copy', 'styles'],
-    'elements',
+    ['elements', 'js'],
     ['jshint', 'images', 'fonts', 'html'],
     'vulcanize','rename-index', // 'cache-config',
     cb);

package.json

@@ -7,8 +7,10 @@
     "glob": "^5.0.6",
     "gulp": "^3.8.5",
     "gulp-autoprefixer": "^2.1.0",
+    "gulp-babel": "^5.2.1",
     "gulp-cache": "^0.2.8",
     "gulp-changed": "^1.0.0",
+    "gulp-crisper": "0.0.5",
     "gulp-cssmin": "^0.1.7",
     "gulp-flatten": "0.0.4",
     "gulp-if": "^1.2.1",
@@ -19,6 +21,7 @@
     "gulp-rename": "^1.2.0",
     "gulp-replace": "^0.5.3",
     "gulp-size": "^1.0.0",
+    "gulp-sourcemaps": "^1.6.0",
     "gulp-uglify": "^1.2.0",
     "gulp-useref": "^1.1.2",
     "gulp-vulcanize": "^6.0.0",
@@ -38,4 +41,4 @@
   "engines": {
     "node": ">=0.10.0"
   }
-}
+}