* @return Cons
   */
  public static Cons listDirectoryFiles(String directory) {
    directory = Stella.translateLogicalPathname(Stella.fileNameAsDirectory(directory));
    Stella.ensureFileExists(directory, "list-directory-files");
    { Cons files = Stella.javaListDirectoryFiles(directory);

      return (files.sort(null));
    }
  }