[win][fs] path.toNamespacedPath does nothing

[AlttiRi]

What version of Bun is running?

1.0.23

What platform is your computer?

Window 10

What steps can reproduce the bug?

import path from "node:path";

const fp1 = "C:\\Downloads\\bun-windows-x64\\bun.exe";
const fp2 = "bun.exe";
const fp3 = "\\\\KEENETIC\\USB";
const fp4 = "\\\\KEENETIC\\USB\\A";
console.log(path.toNamespacedPath(fp1));
console.log(path.toNamespacedPath(fp2));
console.log(path.toNamespacedPath(fp2) === "\\\\?\\" + path.resolve(fp2));
console.log(path.toNamespacedPath(fp3));
console.log(path.toNamespacedPath(fp4));

What is the expected behavior?

\\?\C:\Downloads\bun-windows-x64\bun.exe
\\?\C:\Downloads\bun-windows-x64\bun.exe
true                               
\\?\UNC\KEENETIC\USB\
\\?\UNC\KEENETIC\USB\A

What do you see instead?

C:\Downloads\bun-windows-x64\bun.exe
bun.exe
false
\\KEENETIC\USB
\\KEENETIC\USB\A

Additional information

Rel:

• [win][fs] There is no support of long paths #8246
• [win][fs] Some functions do not support tailing dot "." and space " " in a filename #8836
• [win][fs] Fails to open Win32 device namespace verbatim prefixed filepaths (\\.\, \\.\UNC\) #8248

[jdalton]

Context:
https://nodejs.org/api/path.html#pathtonamespacedpathpath

bun/src/bun.js/bindings/Path.cpp

Lines 125 to 127 in c21dc25

	auto argCount = static_cast<uint16_t>(callFrame->argumentCount());
	// TODO:
	return JSC::JSValue::encode(callFrame->argument(0));

See zig's wToPrefixedFileW

[paperclover]

Fixed in #8469