From d4b1d9babfb4b9ed4f4b12d56d52dee233e862da Mon Sep 17 00:00:00 2001
From: Tim Neutkens <timneutkens@me.com>
Date: Tue, 16 Jan 2018 11:29:57 +0100
Subject: [PATCH] Add support for transpiling certain packages in node_modules
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Thanks to @giuseppeg’s work in https://github.com/zeit/next.js/pull/3319
---
 server/build/webpack/base.config.js | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/server/build/webpack/base.config.js b/server/build/webpack/base.config.js
index c57556dba5108..8bfaa96fa80b1 100644
--- a/server/build/webpack/base.config.js
+++ b/server/build/webpack/base.config.js
@@ -25,6 +25,28 @@ const interpolateNames = new Map(defaultPages.map((p) => {
   return [path.join(nextPagesDir, p), `dist/bundles/pages/${p}`]
 }))
 
+function shouldTranspileModule (transpileModules, path) {
+  return (transpileModules || []).some(pattern => {
+    if (!(pattern instanceof RegExp)) {
+      const message = `Incorrect pattern in config.transpileModules: "${pattern}".` +
+        'It accepts an array of regular expression'
+      throw new Error(message)
+    }
+
+    return pattern.test(path)
+  })
+}
+
+function excludeModules (config) {
+  return (str) => {
+    if (shouldTranspileModule(config.transpileModules, str)) {
+      return false
+    }
+
+    return /node_modules/.test(str) && str.indexOf(nextPagesDir) !== 0
+  }
+}
+
 function babelConfig (dir, isServer) {
   const mainBabelOptions = {
     cacheDirectory: true,
@@ -193,7 +215,7 @@ export default async function baseConfig (dir, {dev = false, isServer = false, b
         {
           test: /\.+(js|jsx)$/,
           include: [dir],
-          exclude: /node_modules/,
+          exclude: excludeModules(config),
           use: {
             loader: 'babel-loader',
             options: babelLoaderOptions
@@ -202,7 +224,7 @@ export default async function baseConfig (dir, {dev = false, isServer = false, b
         {
           test: /\.+(ts|tsx)$/,
           include: [dir],
-          exclude: /node_modules/,
+          exclude: excludeModules(config),
           use: [
             {
               loader: 'babel-loader',