From 49ccbe1b9e69d124bbe29c3a029dd58eed04fb08 Mon Sep 17 00:00:00 2001
From: Jim Vomero <jamesvomero@gmail.com>
Date: Fri, 12 Sep 2025 12:55:17 -0400
Subject: [PATCH] fix(EMULSIF-57): preserve variables in JS minification

---
 config/babel.config.js           | 12 +++++++++++-
 config/webpack/optimizers.js     | 11 ++++++++++-
 config/webpack/webpack.common.js |  4 ++++
 package.json                     |  1 +
 4 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/config/babel.config.js b/config/babel.config.js
index 5ef7c85..6e040d9 100644
--- a/config/babel.config.js
+++ b/config/babel.config.js
@@ -1,7 +1,17 @@
 export default (api) => {
   api.cache(true);
 
-  const presets = [['minify', { builtIns: false }]];
+  const presets = [
+    [
+      'minify',
+      {
+        builtIns: false,
+        mangle: {
+          reserved: ['Drupal', 'drupalSettings', 'once'],
+        },
+      },
+    ],
+  ];
   const comments = false;
 
   return { presets, comments };
diff --git a/config/webpack/optimizers.js b/config/webpack/optimizers.js
index e8b5462..f620516 100644
--- a/config/webpack/optimizers.js
+++ b/config/webpack/optimizers.js
@@ -1,4 +1,5 @@
 import ImageMinimizerPlugin from 'image-minimizer-webpack-plugin';
+import TerserPlugin from 'terser-webpack-plugin';
 
 const ImageMinimizer = new ImageMinimizerPlugin({
   minimizer: {
@@ -12,6 +13,14 @@ const ImageMinimizer = new ImageMinimizerPlugin({
   },
 });
 
+const TerserMinimizer = new TerserPlugin({
+  terserOptions: {
+    mangle: {
+      reserved: ['Drupal', 'drupalSettings', 'once'],
+    },
+  },
+});
+
 export default {
-  minimizer: [ImageMinimizer],
+  minimizer: [ImageMinimizer, TerserMinimizer],
 };
diff --git a/config/webpack/webpack.common.js b/config/webpack/webpack.common.js
index 44c2fff..e28da8b 100644
--- a/config/webpack/webpack.common.js
+++ b/config/webpack/webpack.common.js
@@ -230,6 +230,10 @@ const buildEntries = () => {
 export default {
   target: 'web',
   stats: { errorDetails: true },
+  externals: {
+    drupal: 'Drupal',
+    drupalSettings: 'drupalSettings',
+  },
   entry: buildEntries(),
   module: {
     rules: [
diff --git a/package.json b/package.json
index 8fefc39..a640556 100644
--- a/package.json
+++ b/package.json
@@ -117,6 +117,7 @@
     "stylelint-selector-bem-pattern": "^4.0.1",
     "stylelint-webpack-plugin": "^5.0.1",
     "svg-spritemap-webpack-plugin": "^5.0.1",
+    "terser-webpack-plugin": "^5.3.9",
     "token-transformer": "^0.0.33",
     "twig-drupal-filters": "^3.2.0",
     "twig-testing-library": "^1.2.0",