code: void formatLocalWeekday(StringBuilder b, ZonedDateTime d, int width, FieldVariants weekdays, int firstDay) {
      if (width > 2) {
        formatWeekday(b, d, width, weekdays);
        return;
      }
      if (width == 2) {
        b.append('0');
      }
      formatWeekdayNumeric(b, d, firstDay);
    }
docs: Format the numeric weekday, or the format name variant.