Function pathToFileURL

lib/internal/url.js:1651–1691

(filepath, options = kEmptyObject)

}

function pathToFileURL(filepath, options = kEmptyObject) {
  const windows = options?.windows ?? isWindows;
  const isUNC = windows && StringPrototypeStartsWith(filepath, '\\\\');
  let resolved = isUNC ?
    filepath :
    (windows ? path.win32.resolve(filepath) : path.posix.resolve(filepath));
  if (isUNC || (windows && StringPrototypeStartsWith(resolved, '\\\\'))) {
    // UNC path format: \\server\share\resource
    // Handle extended UNC path and standard UNC path
    // "\\?\UNC\" path prefix should be ignored.
    // Ref: https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation
    const isExtendedUNC = StringPrototypeStartsWith(resolved, '\\\\?\\UNC\\');
    const prefixLength = isExtendedUNC ? 8 : 2;
    const hostnameEndIndex = StringPrototypeIndexOf(resolved, '\\', prefixLength);
    if (hostnameEndIndex === -1) {
      throw new ERR_INVALID_ARG_VALUE(
        'path',
        resolved,
        'Missing UNC resource path',
      );
    }
    if (hostnameEndIndex === 2) {
      throw new ERR_INVALID_ARG_VALUE(
        'path',
        resolved,
        'Empty UNC servername',
      );
    }
    const hostname = StringPrototypeSlice(resolved, prefixLength, hostnameEndIndex);
    return new URL(StringPrototypeSlice(resolved, hostnameEndIndex), hostname, kCreateURLFromWindowsPathSymbol);
  }
  // path.resolve strips trailing slashes so we must add them back
  const filePathLast = StringPrototypeCharCodeAt(filepath,
                                                 filepath.length - 1);
  if ((filePathLast === CHAR_FORWARD_SLASH ||
       ((windows ?? isWindows) && filePathLast === CHAR_BACKWARD_SLASH)) &&
      resolved[resolved.length - 1] !== path.sep)
    resolved += '/';

  return new URL(resolved, undefined, windows ? kCreateURLFromWindowsPathSymbol : kCreateURLFromPosixPathSymbol);
}

function toPathIfFileURL(fileURLOrPath) {
  if (!isURL(fileURLOrPath))