Enable development and production bundling with Webpack

runtime/JavaScript/package.json

@@ -2,7 +2,8 @@
   "name": "antlr4",
   "version": "4.9.1",
   "description": "JavaScript runtime for ANTLR4",
-  "main": "src/antlr4/index.js",
+  "main": "src/index.js",
+  "module": "dist/antlr4.js",
   "repository": "antlr/antlr4.git",
   "keywords": [
     "lexer",
@@ -25,7 +26,7 @@
     "ini": "1.3.6"
   },
   "scripts": {
-    "build": "webpack"
+    "build": "webpack --mode=development && webpack --mode=production"
   },
   "engines": {
     "node": ">=14"

runtime/JavaScript/webpack.config.js

@@ -1,28 +1,32 @@
 const path = require('path');
 
-module.exports = {
-    mode: "production",
-    entry: './src/antlr4/index.js',
-    output: {
-        filename: 'antlr4.js',
-        path: path.resolve(__dirname, 'dist'),
-        // the name of the exported antlr4
-        library: "antlr4",
-        libraryTarget: 'window'
-    },
-    node: {
-        module: "empty",
-        net: "empty",
-        fs: "empty"
-    },
-    target: "web",
-    module: {
-        rules: [{
-            test: /\.js$/,
-            exclude: /node_modules/,
-            use: {
-                loader: 'babel-loader',
-            }
-        }]
-    }
-}
+module.exports = (env, argv) => {
+    return {
+        entry: './src/antlr4/index.js',
+        output: {
+            filename:
+                argv.mode === 'production' ? 'antlr4.min.js' : 'antlr4.js',
+            path: path.resolve(__dirname, 'dist'),
+            // the name of the exported antlr4
+            library: 'antlr4',
+            libraryTarget: 'umd',
+        },
+        node: {
+            module: 'empty',
+            net: 'empty',
+            fs: 'empty',
+        },
+        target: 'web',
+        module: {
+            rules: [
+                {
+                    test: /\.js$/,
+                    exclude: /node_modules/,
+                    use: {
+                        loader: 'babel-loader',
+                    },
+                },
+            ],
+        },
+    };
+};