From 35f525e1b4212ec9a3757be0c75e78bea8304aed Mon Sep 17 00:00:00 2001
From: Francesco Trotta <github@fasttime.org>
Date: Tue, 5 Oct 2021 07:42:08 +0200
Subject: [PATCH] lib: fix regular expression to detect `/` and `\`

Fixes #40305
---
 lib/internal/modules/esm/resolve.js              | 2 +-
 test/es-module/test-esm-encoded-path.mjs         | 3 +++
 test/es-module/test-esm-exports.mjs              | 5 ++++-
 test/es-module/test-esm-imports.mjs              | 6 ++++--
 test/es-module/test-esm-pkgname.mjs              | 4 ++++
 test/fixtures/es-modules/pkgimports/package.json | 3 ++-
 test/fixtures/es-modules/test-esm-comma,.mjs     | 1 +
 7 files changed, 19 insertions(+), 5 deletions(-)
 create mode 100644 test/fixtures/es-modules/test-esm-comma,.mjs

diff --git a/lib/internal/modules/esm/resolve.js b/lib/internal/modules/esm/resolve.js
index 1a28f994ec612c..e9fcfec8284b3b 100644
--- a/lib/internal/modules/esm/resolve.js
+++ b/lib/internal/modules/esm/resolve.js
@@ -356,7 +356,7 @@ function resolveDirectoryEntry(search) {
   return resolveExtensions(new URL('index', search));
 }
 
-const encodedSepRegEx = /%2F|%2C/i;
+const encodedSepRegEx = /%2F|%5C/i;
 /**
  * @param {URL} resolved
  * @param {string | URL | undefined} base
diff --git a/test/es-module/test-esm-encoded-path.mjs b/test/es-module/test-esm-encoded-path.mjs
index 351cb7eab887b4..067ce6066697b6 100644
--- a/test/es-module/test-esm-encoded-path.mjs
+++ b/test/es-module/test-esm-encoded-path.mjs
@@ -2,5 +2,8 @@ import '../common/index.mjs';
 import assert from 'assert';
 // ./test-esm-ok.mjs
 import ok from '../fixtures/es-modules/test-%65%73%6d-ok.mjs';
+// ./test-esm-comma,.mjs
+import comma from '../fixtures/es-modules/test-esm-comma%2c.mjs';
 
 assert(ok);
+assert(comma);
diff --git a/test/es-module/test-esm-exports.mjs b/test/es-module/test-esm-exports.mjs
index e6182a16e736eb..3a3fccdb0275ec 100644
--- a/test/es-module/test-esm-exports.mjs
+++ b/test/es-module/test-esm-exports.mjs
@@ -171,10 +171,13 @@ import fromInside from '../fixtures/node_modules/pkgexports/lib/hole.js';
     }));
   }
 
-  // The use of %2F escapes in paths fails loading
+  // The use of %2F and %5C escapes in paths fails loading
   loadFixture('pkgexports/sub/..%2F..%2Fbar.js').catch(mustCall((err) => {
     strictEqual(err.code, 'ERR_INVALID_MODULE_SPECIFIER');
   }));
+  loadFixture('pkgexports/sub/..%5C..%5Cbar.js').catch(mustCall((err) => {
+    strictEqual(err.code, 'ERR_INVALID_MODULE_SPECIFIER');
+  }));
 
   // Package export with numeric index properties must throw a validation error
   loadFixture('pkgexports-numeric').catch(mustCall((err) => {
diff --git a/test/es-module/test-esm-imports.mjs b/test/es-module/test-esm-imports.mjs
index 9dc78199012cd7..77726c06f101b2 100644
--- a/test/es-module/test-esm-imports.mjs
+++ b/test/es-module/test-esm-imports.mjs
@@ -53,13 +53,15 @@ const { requireImport, importImport } = importer;
     // Backtracking below the package base
     ['#subpath/sub/../../../belowbase', 'request is not a valid subpath'],
     // Percent-encoded slash errors
-    ['#external/subpath/x%2Fy', 'must not include encoded "/"'],
+    ['#external/subpath/x%2Fy', 'must not include encoded "/" or "\\"'],
+    ['#external/subpath/x%5Cy', 'must not include encoded "/" or "\\"'],
     // Target must have a name
     ['#', '#'],
     // Initial slash target must have a leading name
     ['#/initialslash', '#/initialslash'],
     // Percent-encoded target paths
-    ['#percent', 'must not include encoded "/"'],
+    ['#encodedslash', 'must not include encoded "/" or "\\"'],
+    ['#encodedbackslash', 'must not include encoded "/" or "\\"'],
   ]);
 
   for (const [specifier, expected] of invalidImportSpecifiers) {
diff --git a/test/es-module/test-esm-pkgname.mjs b/test/es-module/test-esm-pkgname.mjs
index 06b5d2d104df63..5090d6c22ce689 100644
--- a/test/es-module/test-esm-pkgname.mjs
+++ b/test/es-module/test-esm-pkgname.mjs
@@ -7,6 +7,10 @@ importFixture('as%2Ff').catch(mustCall((err) => {
   strictEqual(err.code, 'ERR_INVALID_MODULE_SPECIFIER');
 }));
 
+importFixture('as%5Cf').catch(mustCall((err) => {
+  strictEqual(err.code, 'ERR_INVALID_MODULE_SPECIFIER');
+}));
+
 importFixture('as\\df').catch(mustCall((err) => {
   strictEqual(err.code, 'ERR_INVALID_MODULE_SPECIFIER');
 }));
diff --git a/test/fixtures/es-modules/pkgimports/package.json b/test/fixtures/es-modules/pkgimports/package.json
index cebe36b350fa50..5b2f2a2ac5dd5f 100644
--- a/test/fixtures/es-modules/pkgimports/package.json
+++ b/test/fixtures/es-modules/pkgimports/package.json
@@ -26,6 +26,7 @@
     "#": "./test.js",
     "#/initialslash": "./test.js",
     "#notfound": "./notfound.js",
-    "#percent": "./..%2F/x.js"
+    "#encodedslash": "./..%2F/x.js",
+    "#encodedbackslash": "./..%5C/x.js"
   }
 }
diff --git a/test/fixtures/es-modules/test-esm-comma,.mjs b/test/fixtures/es-modules/test-esm-comma,.mjs
new file mode 100644
index 00000000000000..0a5f91dc35ef5c
--- /dev/null
+++ b/test/fixtures/es-modules/test-esm-comma,.mjs
@@ -0,0 +1 @@
+export default ',';