class Addressable::URI

def self.normalize_path(path)
  # Section 5.2.4 of RFC 3986
  return nil if path.nil?
  normalized_path = path.dup
  begin
    mod = nil
    mod ||= normalized_path.gsub!(RULE_2A, SLASH)
    pair = normalized_path.match(RULE_2B_2C)
    parent, current = pair[1], pair[2] if pair
    if pair && ((parent != SELF_REF && parent != PARENT) ||
        (current != SELF_REF && current != PARENT))
      mod ||= normalized_path.gsub!(
        Regexp.new(
          "/#{Regexp.escape(parent.to_s)}/\\.\\./|" +
          "(/#{Regexp.escape(current.to_s)}/\\.\\.$)"
        ), SLASH
      )
    end
    mod ||= normalized_path.gsub!(RULE_2D, EMPTY_STR)
    # Non-standard, removes prefixed dotted segments from path.
    mod ||= normalized_path.gsub!(RULE_PREFIXED_PARENT, SLASH)
  end until mod.nil?
  return normalized_path
end