code: function processPath(options) {
      const cwd = (options && options.cwd) || process.cwd();
      let extensions = (options && options.extensions) || [".js"];
  
      extensions = extensions.map(ext => ext.replace(/^\./u, ""));
  
      let suffix = "/**";
  
      if (extensions.length === 1) {
          suffix += `/*.${extensions[0]}`;
      } else {
          suffix += `/*.{${extensions.join(",")}}`;
      }
  
      /**
       * A function that converts a directory name to a glob pattern
       *
       * @param {string} pathname The directory path to be modified
       * @returns {string} The glob path or the file path itself
       * @private
       */
      return function(pathname) {
          if (pathname === "") {
              return "";
          }
  
          let newPath = pathname;
          const resolvedPath = path.resolve(cwd, pathname);
  
          if (directoryExists(resolvedPath)) {
              newPath = pathname.replace(/[/\\]$/u, "") + suffix;
          }
  
          return pathUtils.convertPathToPosix(newPath);
      };
  }
docs: Checks if a provided path is a directory and returns a glob string matching
  all files under that directory if so, the path itself otherwise.
  
  Reason for this is that `glob` needs `/**` to collect all the files under a
  directory where as our previous implementation without `glob` simply walked
  a directory that is passed. So this is to maintain backwards compatibility.
  
  Also makes sure all path separators are POSIX style for `glob` compatibility.
  
  @param {Object}   [options]                    An options object
  @param {string[]} [options.extensions=[".js"]] An array of accepted extensions
  @param {string}   [options.cwd=process.cwd()]  The cwd to use to resolve relative pathnames
  @returns {Function} A function that takes a pathname and returns a glob that
  matches all files with the provided extensions if
  pathname is a directory.