From be9a1ec1d189667a8c2d6bd4ddb661c985f9da87 Mon Sep 17 00:00:00 2001
From: Gilles De Mey <gilles.de.mey@gmail.com>
Date: Mon, 22 Oct 2018 20:42:53 +0200
Subject: [PATCH] module: allow passing a directory to createRequireFromPath

Fixes: https://github.com/nodejs/node/issues/23710

PR-URL: https://github.com/nodejs/node/pull/23818
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
---
 doc/api/modules.md                             |  2 +-
 lib/internal/modules/cjs/loader.js             | 15 ++++++++++++---
 ...est-module-create-require-from-directory.js | 18 ++++++++++++++++++
 3 files changed, 31 insertions(+), 4 deletions(-)
 create mode 100644 test/parallel/test-module-create-require-from-directory.js

diff --git a/doc/api/modules.md b/doc/api/modules.md
index d52d4ddac5f32e..8638b137ade732 100644
--- a/doc/api/modules.md
+++ b/doc/api/modules.md
@@ -916,7 +916,7 @@ added: v10.12.0
 
 ```js
 const { createRequireFromPath } = require('module');
-const requireUtil = createRequireFromPath('../src/utils');
+const requireUtil = createRequireFromPath('../src/utils/');
 
 // Require `../src/utils/some-tool`
 requireUtil('./some-tool');
diff --git a/lib/internal/modules/cjs/loader.js b/lib/internal/modules/cjs/loader.js
index 96b5e8b7b881b6..5df34cb3f022b4 100644
--- a/lib/internal/modules/cjs/loader.js
+++ b/lib/internal/modules/cjs/loader.js
@@ -825,9 +825,18 @@ Module.runMain = function() {
 };
 
 Module.createRequireFromPath = (filename) => {
-  const m = new Module(filename);
-  m.filename = filename;
-  m.paths = Module._nodeModulePaths(path.dirname(filename));
+  // Allow a directory to be passed as the filename
+  const trailingSlash =
+    filename.endsWith(path.sep) || path.sep !== '/' && filename.endsWith('\\');
+
+  const proxyPath = trailingSlash ?
+    path.join(filename, 'noop.js') :
+    filename;
+
+  const m = new Module(proxyPath);
+  m.filename = proxyPath;
+
+  m.paths = Module._nodeModulePaths(m.path);
   return makeRequireFunction(m);
 };
 
diff --git a/test/parallel/test-module-create-require-from-directory.js b/test/parallel/test-module-create-require-from-directory.js
new file mode 100644
index 00000000000000..f043adacf994d8
--- /dev/null
+++ b/test/parallel/test-module-create-require-from-directory.js
@@ -0,0 +1,18 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+const path = require('path');
+
+const { createRequireFromPath } = require('module');
+
+const fixPath = path.resolve(__dirname, '..', 'fixtures');
+const p = path.join(fixPath, path.sep);
+
+const req = createRequireFromPath(p);
+const reqFromNotDir = createRequireFromPath(fixPath);
+
+assert.strictEqual(req('./baz'), 'perhaps I work');
+assert.throws(() => {
+  reqFromNotDir('./baz');
+}, { code: 'MODULE_NOT_FOUND' });