The ultimate split path, with a single regex

regex_split_path.js

/**
 * The ultimate split path.
 * Extracts dirname, filename, extension, and trailing URL params.
 * Correct handles:
 *   empty dirname,
 *   empty extension,
 *   random input (extracts as filename),
 *   multiple extensions (only extracts the last one),
 *   dotfiles (however, will extract extension if there is one)
 * @param  {string} path
 * @return {Object} Object containing fields "dirname", "filename", "extension", and "params"
 *
 * See: https://regexr.com/3sqfe
 *
 * /!\ path such as \var\www\www.example.com\.hidden\index.php returns .hidden\index as extension
 */
var splitPath = function(path) {
  var result = path.replace(/\\/g, "/").match(/(.*\/)?(\..*?|.*?)(\.[^.]*?)?(#.*$|\?.*$|$)/);
  return {
    dirname: result[1] || "",
    filename: result[2] || "",
    extension: result[3] || "",
    params: result[4] || ""
  };
};