class TZInfo::DataSources::PosixTimeZoneParser

def parse_rule(s, type)
  check_scan(s, /,(?: (?: J(\d+) ) | (\d+) | (?: M(\d+)\.(\d)\.(\d) ) )/x)
  julian_day_of_year = s[1]
  absolute_day_of_year = s[2]
  month = s[3]
  week = s[4]
  day_of_week = s[5]
  if s.scan(/\//)
    check_scan(s, /([-+]?\d+)(?::(\d+)(?::(\d+))?)?/)
    transition_at = get_seconds_after_midnight_from_hms(s[1], s[2], s[3])
  else
    transition_at = 7200
  end
  begin
    if julian_day_of_year
      JulianDayOfYearTransitionRule.new(julian_day_of_year.to_i, transition_at)
    elsif absolute_day_of_year
      AbsoluteDayOfYearTransitionRule.new(absolute_day_of_year.to_i, transition_at)
    elsif week == '5'
      LastDayOfMonthTransitionRule.new(month.to_i, day_of_week.to_i, transition_at)
    else
      DayOfMonthTransitionRule.new(month.to_i, week.to_i, day_of_week.to_i, transition_at)
    end
  rescue ArgumentError => e
    raise InvalidPosixTimeZone, "Invalid #{type} rule in POSIX-style time zone string: #{e}"
  end
end