docs: private static boolean dateByWeek(
          DateTimeFormatterBuilder bld,
          Collection<DateTimeFieldType> fields,
          boolean extended,
          boolean strictISO) {
          
          boolean reducedPrec = false;
          if (fields.remove(DateTimeFieldType.weekyear())) {
              bld.append(Constants.we);
              if (fields.remove(DateTimeFieldType.weekOfWeekyear())) {
                  appendSeparator(bld, extended);
                  bld.appendLiteral('W');
                  bld.appendWeekOfWeekyear(2);
                  if (fields.remove(DateTimeFieldType.dayOfWeek())) {
                      // YYYY-WWW-D/YYYYWWWD
                      appendSeparator(bld, extended);
                      bld.appendDayOfWeek(1);
                  } else {
                      // YYYY-WWW/YYYY-WWW
                      reducedPrec = true;
                  }
              } else {
                  if (fields.remove(DateTimeFieldType.dayOfWeek())) {
                      // YYYY-W-D/YYYYW-D (non-iso)
                      checkNotStrictISO(fields, strictISO);
                      appendSeparator(bld, extended);
                      bld.appendLiteral('W');
                      bld.appendLiteral('-');
                      bld.appendDayOfWeek(1);
                  } else {
                      // YYYY/YYYY
                      reducedPrec = true;
                  }
              }
              
          } else if (fields.remove(DateTimeFieldType.weekOfWeekyear())) {
              bld.appendLiteral('-');
              bld.appendLiteral('W');
              bld.appendWeekOfWeekyear(2);
              if (fields.remove(DateTimeFieldType.dayOfWeek())) {
                  // -WWW-D/-WWWD
                  appendSeparator(bld, extended);
                  bld.appendDayOfWeek(1);
              } else {
                  // -WWW/-WWW
                  reducedPrec = true;
              }
          } else if (fields.remove(DateTimeFieldType.dayOfWeek())) {
              // -W-D/-W-D
              bld.appendLiteral('-');
              bld.appendLiteral('W');
              bld.appendLiteral('-');
              bld.appendDayOfWeek(1);
          }
          return reducedPrec;
      }