feat: add a top-level terser option to allow users to customize the…

… minifier (#6752)

packages/@vue/cli-service/lib/config/terserOptions.js

@@ -1,40 +1,110 @@
-module.exports = options => ({
-  terserOptions: {
-    compress: {
-      // turn off flags with small gains to speed up minification
-      arrows: false,
-      collapse_vars: false, // 0.3kb
-      comparisons: false,
-      computed_props: false,
-      hoist_funs: false,
-      hoist_props: false,
-      hoist_vars: false,
-      inline: false,
-      loops: false,
-      negate_iife: false,
-      properties: false,
-      reduce_funcs: false,
-      reduce_vars: false,
-      switches: false,
-      toplevel: false,
-      typeofs: false,
-
-      // a few flags with noticeable gains/speed ratio
-      // numbers based on out of the box vendor bundle
-      booleans: true, // 0.7kb
-      if_return: true, // 0.4kb
-      sequences: true, // 0.7kb
-      unused: true, // 2.3kb
-
-      // required features to drop conditional branches
-      conditionals: true,
-      dead_code: true,
-      evaluate: true
+// @ts-check
+const TerserPlugin = require('terser-webpack-plugin')
+
+const genTerserOptions = (defaultOptions, options) => {
+  const userOptions = options.terser && options.terser.terserOptions
+  // user's config is first
+  return {
+    ...defaultOptions,
+    ...userOptions
+  }
+}
+
+const terserMinify = (options) => ({
+  terserOptions: genTerserOptions(
+    {
+      compress: {
+        // turn off flags with small gains to speed up minification
+        arrows: false,
+        collapse_vars: false, // 0.3kb
+        comparisons: false,
+        computed_props: false,
+        hoist_funs: false,
+        hoist_props: false,
+        hoist_vars: false,
+        inline: false,
+        loops: false,
+        negate_iife: false,
+        properties: false,
+        reduce_funcs: false,
+        reduce_vars: false,
+        switches: false,
+        toplevel: false,
+        typeofs: false,
+
+        // a few flags with noticeable gains/speed ratio
+        // numbers based on out of the box vendor bundle
+        booleans: true, // 0.7kb
+        if_return: true, // 0.4kb
+        sequences: true, // 0.7kb
+        unused: true, // 2.3kb
+
+        // required features to drop conditional branches
+        conditionals: true,
+        dead_code: true,
+        evaluate: true
+      },
+      mangle: {
+        safari10: true
+      }
     },
-    mangle: {
-      safari10: true
-    }
-  },
+    options
+  ),
   parallel: options.parallel,
   extractComments: false
 })
+
+// `terserOptions` options will be passed to `esbuild`
+// Link to options - https://esbuild.github.io/api/#minify
+const esbuildMinify = (options) => ({
+  minify: TerserPlugin.esbuildMinify,
+  terserOptions: genTerserOptions(
+    {
+      minify: false,
+      minifyWhitespace: true,
+      minifyIdentifiers: false,
+      minifySyntax: true
+    },
+    options
+  ),
+  parallel: options.parallel
+})
+
+// `terserOptions` options will be passed to `swc` (`@swc/core`)
+// Link to options - https://swc.rs/docs/config-js-minify
+const swcMinify = (options) => ({
+  minify: TerserPlugin.swcMinify,
+  terserOptions: genTerserOptions(
+    {
+      compress: {
+        unused: true
+      },
+      mangle: true
+    },
+    options
+  ),
+  parallel: options.parallel
+})
+
+// `terserOptions` options will be passed to `uglify-js`
+// Link to options - https://github.com/mishoo/UglifyJS#minify-options
+const uglifyJsMinify = (options) => ({
+  minify: TerserPlugin.uglifyJsMinify,
+  terserOptions: genTerserOptions({}, options),
+  parallel: options.parallel
+})
+
+// Currently we do not allow custom minify function
+const getMinify = (options) => {
+  const { minify = 'terser' } = options.terser || {}
+
+  const minifyMap = {
+    terser: terserMinify,
+    esbuild: esbuildMinify,
+    swc: swcMinify,
+    uglifyJs: uglifyJsMinify
+  }
+  return minifyMap[minify](options)
+}
+
+module.exports = getMinify

packages/@vue/cli-service/lib/options.js

@@ -59,6 +59,12 @@ const schema = createSchema(joi => joi.object({
   lintOnSave: joi.any().valid(true, false, 'error', 'warning', 'default'),
   pwa: joi.object(),
 
+  // terser
+  terser: joi.object({
+    minify: joi.string().valid('terser', 'esbuild', 'swc', 'uglifyJs'),
+    terserOptions: joi.object()
+  }),
+
   // 3rd party plugin options
   pluginOptions: joi.object()
 }))

packages/@vue/cli-service/types/ProjectOptions.d.ts

@@ -1,6 +1,8 @@
 import ChainableWebpackConfig = require('webpack-chain')
 import { Configuration as WebpackOptions } from 'webpack'
 
+type PredefinedOptions<T> = T & { [key: string]: any }
+
 type PageEntry = string | string[];
 
 interface PageConfig {
@@ -153,6 +155,31 @@ interface ProjectOptions {
    */
   pwa?: object;
 
+  /**
+   * set terser-webpack-plugin minify and terserOptions
+   */
+  terser?: {
+    /**
+     * Supported minify: [terser](https://github.com/webpack-contrib/terser-webpack-plugin#minify), [esbuild](https://github.com/webpack-contrib/terser-webpack-plugin#esbuild), [swc](https://github.com/webpack-contrib/terser-webpack-plugin#swc), [uglifyJs](https://github.com/webpack-contrib/terser-webpack-plugin#uglify-js). currently we do not allow custom minify function
+     *
+     * In the non-terser case, you should install the corresponding package (eg. `npm i esbuild -D`)
+     *
+     */
+    minify: 'terser' | 'esbuild' | 'swc' | 'uglifyJs';
+    /**
+     * `terserOptions` options will be passed to minify
+     *
+     * [All options for `terser`](https://github.com/webpack-contrib/terser-webpack-plugin#terseroptions)
+     *
+     * [All options for `esbuild`](https://github.com/evanw/esbuild/blob/master/lib/shared/types.ts#L160-L174)
+     *
+     * [All options for `swc`](https://swc.rs/docs/config-js-minify)
+     *
+     * [All options for `uglifyJs`](https://github.com/mishoo/UglifyJS#minify-options)
+     */
+    terserOptions?: PredefinedOptions<import("terser").MinifyOptions>;
+  };
+
   /**
    * This is an object that doesn't go through any schema validation, so it can be used to pass arbitrary options to 3rd party plugins
    */