fs,win: fix readdir for named pipe

PR-URL: #56110
Fixes: #56002
Refs: #55623
Refs: #56088
Reviewed-By: Gerhard Stöbich <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>

src/node_file.cc

@@ -1986,8 +1986,29 @@ static void ReadDir(const FunctionCallbackInfo<Value>& args) {
 
   BufferValue path(isolate, args[0]);
   CHECK_NOT_NULL(*path);
+#ifdef _WIN32
+  // On Windows, some API functions accept paths with trailing slashes,
+  // while others do not. This code checks if the input path ends with
+  // a slash (either '/' or '\\') and, if so, ensures that the processed
+  // path also ends with a trailing backslash ('\\').
+  bool slashCheck = false;
+  if (path.ToStringView().ends_with("/") ||
+      path.ToStringView().ends_with("\\")) {
+    slashCheck = true;
+  }
+#endif
+
   ToNamespacedPath(env, &path);
 
+#ifdef _WIN32
+  if (slashCheck) {
+    size_t new_length = path.length() + 1;
+    path.AllocateSufficientStorage(new_length + 1);
+    path.SetLengthAndZeroTerminate(new_length);
+    path.out()[new_length - 1] = '\\';
+  }
+#endif
+
   const enum encoding encoding = ParseEncoding(isolate, args[1], UTF8);
 
   bool with_types = args[2]->IsTrue();

test/parallel/test-fs-readdir-pipe.js

@@ -0,0 +1,21 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const { readdir, readdirSync } = require('fs');
+
+if (!common.isWindows) {
+  common.skip('This test is specific to Windows to test enumerate pipes');
+}
+
+// Ref: https://github.com/nodejs/node/issues/56002
+// This test is specific to Windows.
+
+const pipe = '\\\\.\\pipe\\';
+
+const { length } = readdirSync(pipe);
+assert.ok(length >= 0, `${length} is not greater or equal to 0`);
+
+readdir(pipe, common.mustSucceed((files) => {
+  assert.ok(files.length >= 0, `${files.length} is not greater or equal to 0`);
+}));