docs: private static void convertSelectPartHelper(
        Builder<SoyMsgPart> newMsgPartsBuilder,
        StringBuilder currRawTextSb,
        SoyMsgSelectPart origSelectPart) {
  
      currRawTextSb.append(getSelectOpenString(origSelectPart.getSelectVarName()));
  
      for (Case<String> selectCase : origSelectPart.getCases()) {
        currRawTextSb.append(getSelectCaseOpenString(selectCase.spec()));
        convertMsgPartsHelper(
            newMsgPartsBuilder, currRawTextSb, selectCase.parts(), /* isInPlrselPart= */ true);
        currRawTextSb.append(getSelectCaseCloseString());
      }
  
      currRawTextSb.append(getSelectCloseString());
    }