perf: speed up uglify-js by using parallel and cache options

lib/builder/webpack/client.mjs

@@ -4,6 +4,7 @@ import webpack from 'webpack'
 import HTMLPlugin from 'html-webpack-plugin'
 import BundleAnalyzer from 'webpack-bundle-analyzer'
 import MiniCssExtractPlugin from 'mini-css-extract-plugin'
+import UglifyJsWebpackPlugin from 'uglifyjs-webpack-plugin'
 
 import VueSSRClientPlugin from './plugins/vue/client'
 import BaseConfig from './base'
@@ -105,8 +106,20 @@ export default class WebpackClientConfig extends BaseConfig {
       }
     }
 
+    // Make uglifyjs faster
+    if (!this.options.dev && !config.optimization.minimizer) {
+      // https://github.com/webpack-contrib/uglifyjs-webpack-plugin
+      config.optimization.minimizer = [
+        new UglifyJsWebpackPlugin({
+          parallel: true,
+          cache: true,
+          sourceMap: false
+        })
+      ]
+    }
+
+    // Add HMR support
     if (this.options.dev) {
-      // Add HMR support
       config.entry = [
         // https://github.com/glenjamin/webpack-hot-middleware#config
         `webpack-hot-middleware/client?name=client&reload=true&timeout=30000&path=${

package.json

@@ -102,6 +102,7 @@
     "source-map": "^0.7.2",
     "style-resources-loader": "^1.1.0",
     "time-fix-plugin": "^2.0.0",
+    "uglifyjs-webpack-plugin": "^1.2.4",
     "upath": "^1.0.2",
     "url-loader": "^1.0.1",
     "vue": "^2.5.16",

yarn.lock

@@ -7115,7 +7115,7 @@ uglify-to-browserify@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/uglify-to-browserify/-/uglify-to-browserify-1.0.2.tgz#6e0924d6bda6b5afe349e39a6d632850a0f882b7"
 
-uglifyjs-webpack-plugin@^1.1.1:
+uglifyjs-webpack-plugin@^1.1.1, uglifyjs-webpack-plugin@^1.2.4:
   version "1.2.4"
   resolved "https://registry.yarnpkg.com/uglifyjs-webpack-plugin/-/uglifyjs-webpack-plugin-1.2.4.tgz#5eec941b2e9b8538be0a20fc6eda25b14c7c1043"
   dependencies: