Build: Switch from UglifyJS to SWC minify, make the minified file ES5

More recent UglifyJS versions have started converting regular functions to arrow
ones, making ES5 source file migrated to a ES2015+ minified one. We want to
avoid that even in `1.14.x` as long as we keep the source file in ES5. But the
bigger problem is that we generate ES2015+ minified code even for `1.13.3`
releases which support IE.

This change switches the minfied to SWC and ensures ES5 output. Tests
ensuring this behavior have been added.

Also, GitHub Actions were updated, as the previous versions stopped working.
To avoid this happening in the future, automatic dependabot PRs updating
actions are now enabled.

Fixes gh-629
Closes gh-630
Ref mishoo/UglifyJS#5967
Ref #629

Author: mgol

.github/dependabot.yml

@@ -0,0 +1,13 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: "/"
+    schedule:
+      interval: monthly
+
+    # Group all dependabot version update PRs into one
+    groups:
+      github-actions:
+        applies-to: version-updates
+        patterns:
+          - "*"

.github/workflows/node.js.yml

@@ -15,19 +15,19 @@ jobs:
         NODE_VERSION: [18.x, 20.x, 22.x]
     steps:
     - name: Checkout
-      uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
+      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-    - name: Install xsltproc
+    - name: Install xsltproc & ImageMagick
       run: |
-        sudo apt-get install xsltproc
+        sudo apt-get install xsltproc imagemagick
 
     - name: Use Node.js ${{ matrix.NODE_VERSION }}
-      uses: actions/setup-node@1e60f620b9541d16bece96c5465dc8ee9832be0b # v4.0.3
+      uses: actions/setup-node@1d0ff469b7ec7b3cb9d8673fde0c81c44821de2a # v4.2.0
       with:
         node-version: ${{ matrix.NODE_VERSION }}
 
     - name: Cache
-      uses: actions/cache@0c45773b623bea8c8e75f6c82b208c3cf94ea4f9 # v4.0.2
+      uses: actions/cache@d4323d4df104b026a6aa633fdb11d772146be0bf # v4.2.2
       with:
         path: ~/.npm
         key: ${{ runner.os }}-node-${{ matrix.NODE_VERSION }}-npm-lock-${{ hashFiles('**/package-lock.json') }}

Gruntfile.js

@@ -11,7 +11,6 @@ grunt.loadNpmTasks( "grunt-check-modules" );
 grunt.loadNpmTasks( "grunt-contrib-clean" );
 grunt.loadNpmTasks( "grunt-contrib-copy" );
 grunt.loadNpmTasks( "grunt-contrib-handlebars" );
-grunt.loadNpmTasks( "grunt-contrib-uglify" );
 grunt.loadNpmTasks( "grunt-eslint" );
 
 grunt.initConfig( {
@@ -61,10 +60,7 @@ grunt.initConfig( {
 			dest: "app/dist"
 		}
 	},
-	uglify: {
-		options: {
-			preserveComments: "some"
-		},
+	minify: {
 
 		// DownloadBuilder minified frontend bundle
 		download: {
@@ -87,6 +83,9 @@ grunt.initConfig( {
 	}
 } );
 
+// local tasks
+grunt.loadTasks( "grunt-tasks" );
+
 function log( callback, successMsg, errorMsg ) {
 	return function( error, result, code ) {
 		if ( error && errorMsg ) {
@@ -279,7 +278,7 @@ function buildPackages( folder, callback ) {
 
 grunt.registerTask( "default", [ "check-modules", "eslint", "test" ] );
 
-grunt.registerTask( "build-app", [ "clean", "handlebars", "copy", "uglify" ] );
+grunt.registerTask( "build-app", [ "clean", "handlebars", "copy", "minify" ] );
 
 grunt.registerTask( "build-packages", "Builds zip package of each jQuery UI release specified in config file with all components and lightness theme, inside the given folder", function( folder ) {
 	var done = this.async();

grunt-tasks/minify.js

@@ -0,0 +1,26 @@
+"use strict";
+
+const swc = require( "@swc/core" );
+const swcOptions = require( "../lib/swc-options" );
+
+module.exports = function( grunt ) {
+
+grunt.registerMultiTask( "minify", async function() {
+	const done = this.async();
+
+	for ( const file of this.files ) {
+		const contents = file.src
+			.map( singleFile => grunt.file.read( singleFile ) )
+			.join( "\n" );
+
+		const { code } = await swc.minify( contents, swcOptions );
+
+		grunt.file.write( file.dest, code );
+
+		grunt.log.writeln( `File ${ file.dest } created.` );
+	}
+
+	done();
+} );
+
+};

lib/jquery-ui-files.js

@@ -5,7 +5,8 @@ var stripBanner, glob, noDirectory,
 	fs = require( "node:fs" ),
 	path = require( "node:path" ),
 	sqwish = require( "sqwish" ),
-	UglifyJS = require( "uglify-js" ),
+	swc = require( "@swc/core" ),
+	swcOptions = require( "./swc-options" ),
 	util = require( "./util" ),
 	Files = require( "./files" ),
 	filesCache = {};
@@ -91,7 +92,10 @@ JqueryUiFiles.prototype = {
 				path: file.path.replace( /\.([^.]*)$/, ".min.$1" )
 			};
 			if ( ( /\.js$/i ).test( file.path ) ) {
-				minified[ file.path ].data = UglifyJS.minify( file.data.toString( "utf8" ) ).code;
+				minified[ file.path ].data = swc.minifySync(
+					file.data.toString( "utf8" ),
+					swcOptions
+				).code;
 			} else if ( ( /\.css$/i ).test( file.path ) ) {
 				minified[ file.path ].data = sqwish.minify( file.data.toString( "utf8" ) );
 			}

lib/package.js

@@ -11,7 +11,8 @@ var indexTemplate,
 	sqwish = require( "sqwish" ),
 	ThemeRoller = require( "./themeroller" ),
 	semver = require( "semver" ),
-	UglifyJS = require( "uglify-js" );
+	swc = require( "@swc/core" ),
+	swcOptions = require( "./swc-options" );
 
 indexTemplate = handlebars.compile( fs.readFileSync( __dirname + "/../template/zip/index.html", "utf8" ) );
 
@@ -340,13 +341,8 @@ extend( Package.prototype, {
 		}
 
 		this.jsBundle.promise.then( function( js ) {
-			var minJs;
 			var _banner = banner( pkgJson, jsFileNames, { minify: true } );
-			var uglifyResult = UglifyJS.minify( js );
-			if ( uglifyResult.error ) {
-				throw uglifyResult.error;
-			}
-			minJs = uglifyResult.code;
+			var minJs = swc.minifySync( js, swcOptions ).code;
 			callback( null, _banner + minJs );
 		} ).catch( callback );
 	},

lib/swc-options.js

@@ -0,0 +1,21 @@
+"use strict";
+
+module.exports = {
+	compress: {
+		ecma: 5,
+		hoist_funs: false,
+		loops: false
+	},
+	format: {
+		ecma: 5,
+		asciiOnly: true,
+
+		// That only preserves license comments.
+		// See https://swc.rs/docs/configuration/minification#note-about-comments
+		comments: true
+	},
+	inlineSourcesContent: false,
+	mangle: true,
+	module: false,
+	sourceMap: false
+};