From 972d9218559877f7fff4bb6086afacac8933f8d1 Mon Sep 17 00:00:00 2001
From: Guy Bedford <guybedford@gmail.com>
Date: Sat, 18 Sep 2021 11:57:52 -0700
Subject: [PATCH] module: fix ERR_REQUIRE_ESM for parentPath null

PR-URL: https://github.com/nodejs/node/pull/40145
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 lib/internal/errors.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/internal/errors.js b/lib/internal/errors.js
index 2e1174316d4710..07b7181a588f30 100644
--- a/lib/internal/errors.js
+++ b/lib/internal/errors.js
@@ -1459,8 +1459,8 @@ E('ERR_REQUIRE_ESM',
       return msg;
     }
     const path = require('path');
-    const basename = path.basename(filename) === path.basename(parentPath) ?
-      filename : path.basename(filename);
+    const basename = parentPath && path.basename(filename) ===
+      path.basename(parentPath) ? filename : path.basename(filename);
     if (hasEsmSyntax) {
       msg += `\nInstead change the require of ${basename} in ${parentPath} to` +
         ' a dynamic import() which is available in all CommonJS modules.';