def join_file_uri(scheme, host, path, query)
      str = String.new("#{scheme}://")
      str << host if host
      path = "/#{path}" unless path.start_with?("/".freeze)
      str << URI::Generic::DEFAULT_PARSER.escape(path)
      str << "?#{query}" if query
      str
    end
def join_file_uri(scheme, host, path, query)
      str = String.new("#{scheme}://")
      str << host if host
      path = "/#{path}" unless path.start_with?("/".freeze)
      str << URI::Generic::DEFAULT_PARSER.escape(path)
      str << "?#{query}" if query
      str
    end
Internal: Join file: URI component parts into String.

 Returns String.