From b732c67cbe779e5e96c01b9b49f06895e6fb2f0e Mon Sep 17 00:00:00 2001
From: Antoine du Hamel <duhamelantoine1995@gmail.com>
Date: Sun, 21 Mar 2021 17:00:52 +0100
Subject: [PATCH] fixup! module: clarify require not defined error message

---
 lib/internal/modules/esm/module_job.js       | 19 ++++++++++++++-----
 test/es-module/test-esm-undefined-require.js | 14 ++++++++++++++
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/lib/internal/modules/esm/module_job.js b/lib/internal/modules/esm/module_job.js
index ea10166fdd3536..ae4b7d59a7f231 100644
--- a/lib/internal/modules/esm/module_job.js
+++ b/lib/internal/modules/esm/module_job.js
@@ -12,10 +12,12 @@ const {
   ReflectApply,
   SafeArrayIterator,
   SafeSet,
+  StringPrototypeEndsWith,
   StringPrototypeIncludes,
   StringPrototypeMatch,
   StringPrototypeReplace,
   StringPrototypeSplit,
+  StringPrototypeStartsWith,
 } = primordials;
 
 const { ModuleWrap } = internalBinding('module_wrap');
@@ -154,11 +156,18 @@ class ModuleJob {
     try {
       await this.module.evaluate(timeout, breakOnSigint);
     } catch (e) {
-      if (e.name === 'ReferenceError' &&
-          e.message === 'require is not defined') {
-        e.message += ' in ES module scope. You can use `await import` instead' +
-                     ', or use `.cjs` extension to load the file as CommonJS ' +
-                     'module.';
+      if (e.name === 'ReferenceError' && (
+          e.message === 'require is not defined' ||
+          e.message === 'module is not defined'
+      )) {
+        e.message += ' in ES module scope. You can use `await import` instead';
+
+        if(StringPrototypeEndsWith(this.module.url, '.js') &&
+           StringPrototypeStartsWith(this.module.url, 'file://')) {
+          e.message +=
+            '. It seems you are trying to load a file using `.js` extension ' +
+            'inside a folder containing a `package.json`; you need to use '+ 'the `.cjs` extension to load the file as a CommonJS module';
+        }
       }
       throw e;
     }
diff --git a/test/es-module/test-esm-undefined-require.js b/test/es-module/test-esm-undefined-require.js
index bf5c1d07d71d75..8be47a7b80a2a3 100644
--- a/test/es-module/test-esm-undefined-require.js
+++ b/test/es-module/test-esm-undefined-require.js
@@ -1,5 +1,6 @@
 'use strict';
 const common = require('../common');
+const fixtures = require('../common/fixtures');
 const assert = require('assert');
 
 assert.rejects(
@@ -7,3 +8,16 @@ assert.rejects(
   // eslint-disable-next-line node-core/no-unescaped-regexp-dot
   /use .await import. instead/
 ).then(common.mustCall());
+
+assert.rejects(
+  import('data:text/javascript,require;//.js'),
+  // eslint-disable-next-line node-core/no-unescaped-regexp-dot
+  /^(?!It seems you are trying to load a file using `.js` extension).*$/
+).then(common.mustCall());
+
+assert.rejects(
+  import(fixtures.path('/es-modules/package-type-module/cjs.js')),
+  // eslint-disable-next-line node-core/no-unescaped-regexp-dot
+  /use the .\.cjs. extension to load the file as a CommonJS module/
+).then(common.mustCall());
+