Program: 69018
Project: 69018
Buggy source:
private void synchronize(double height){
  XlsContainer rowContainer=getCurrentContainer();
  ContainerSizeInfo rowSizeInfo=rowContainer.getSizeInfo();
  int startCoordinate=rowSizeInfo.getStartCoordinate();
  int endCoordinate=rowSizeInfo.getEndCoordinate();
  int startColumnIndex=axis.getColumnIndexByCoordinate(startCoordinate);
  int endColumnIndex=axis.getColumnIndexByCoordinate(endCoordinate);
  int maxRowIndex=0;
  int rowIndexes[]=new int[endColumnIndex - startColumnIndex];
  for (int currentColumnIndex=startColumnIndex; currentColumnIndex < endColumnIndex; currentColumnIndex++) {
    int rowIndex=cache.getMaxRowIndex(currentColumnIndex);
    SheetData lastData=cache.getColumnLastData(currentColumnIndex);
    rowIndexes[currentColumnIndex - startColumnIndex]=rowIndex;
    int span=lastData != null ? lastData.getRowSpanInDesign() : 0;
    if (span == 0 || (span == 1 && !isInContainer(lastData,rowContainer))) {
      maxRowIndex=maxRowIndex > rowIndex ? maxRowIndex : rowIndex;
    }
  }
  int startRowIndex=rowContainer.getRowIndex();
  if (maxRowIndex == startRowIndex) {
    maxRowIndex++;
  }
  rowContainer.setRowIndex(maxRowIndex);
  double resize=height / (maxRowIndex - startRowIndex);
  for (int i=startRowIndex; i < maxRowIndex; i++) {
    cache.setRowHeight(i,resize);
  }
  for (int currentColumnIndex=startColumnIndex; currentColumnIndex < endColumnIndex; currentColumnIndex++) {
    int rowspan=maxRowIndex - rowIndexes[currentColumnIndex - startColumnIndex];
    SheetData upstair=cache.getColumnLastData(currentColumnIndex);
    if (rowspan > 0) {
      if (upstair != null && canSpan(upstair,rowContainer)) {
        Type blankType=Type.VERTICAL;
        if (upstair.isBlank()) {
          BlankData blankData=(BlankData)upstair;
          if (blankData.getType() == Type.VERTICAL) {
            upstair.setRowSpan(upstair.getRowSpan() + rowspan);
          }
          blankType=blankData.getType();
        }
 else {
          upstair.setRowSpan(upstair.getRowSpan() + rowspan);
        }
        SheetData realData=getRealData(upstair);
        if (!isInContainer(upstair,rowContainer)) {
          realData.decreasRowSpanInDesign();
        }
        int rowIndex=upstair.getRowIndex();
        for (int p=1; p <= rowspan; p++) {
          BlankData blank=new BlankData(upstair);
          blank.setRowIndex(rowIndex + p);
          blank.setType(blankType);
          cache.addData(currentColumnIndex,blank);
        }
      }
    }
 else     if (upstair.getRowSpanInDesign() > 0 && !isInContainer(upstair,rowContainer)) {
      upstair.decreasRowSpanInDesign();
    }
  }
}

Fixed version (ground truth):
private void synchronize(double height){
  XlsContainer rowContainer=getCurrentContainer();
  ContainerSizeInfo rowSizeInfo=rowContainer.getSizeInfo();
  int startCoordinate=rowSizeInfo.getStartCoordinate();
  int endCoordinate=rowSizeInfo.getEndCoordinate();
  int startColumnIndex=axis.getColumnIndexByCoordinate(startCoordinate);
  int endColumnIndex=axis.getColumnIndexByCoordinate(endCoordinate);
  int maxRowIndex=0;
  int rowIndexes[]=new int[endColumnIndex - startColumnIndex];
  for (int currentColumnIndex=startColumnIndex; currentColumnIndex < endColumnIndex; currentColumnIndex++) {
    int rowIndex=cache.getMaxRowIndex(currentColumnIndex);
    SheetData lastData=cache.getColumnLastData(currentColumnIndex);
    rowIndexes[currentColumnIndex - startColumnIndex]=rowIndex;
    int span=lastData != null ? lastData.getRowSpanInDesign() : 0;
    if (span == 0 || (span == 1 && !isInContainer(lastData,rowContainer))) {
      maxRowIndex=maxRowIndex > rowIndex ? maxRowIndex : rowIndex;
    }
  }
  int startRowIndex=rowContainer.getRowIndex();
  if (maxRowIndex == startRowIndex) {
    maxRowIndex++;
  }
  rowContainer.setRowIndex(maxRowIndex);
  double resize=height / (maxRowIndex - startRowIndex);
  for (int i=startRowIndex; i < maxRowIndex; i++) {
    cache.setRowHeight(i,resize);
  }
  for (int currentColumnIndex=startColumnIndex; currentColumnIndex < endColumnIndex; currentColumnIndex++) {
    int rowspan=maxRowIndex - rowIndexes[currentColumnIndex - startColumnIndex];
    SheetData upstair=cache.getColumnLastData(currentColumnIndex);
    if (rowspan > 0) {
      if (upstair != null && canSpan(upstair,rowContainer)) {
        Type blankType=Type.VERTICAL;
        if (upstair.isBlank()) {
          BlankData blankData=(BlankData)upstair;
          if (blankData.getType() == Type.VERTICAL) {
            upstair.setRowSpan(upstair.getRowSpan() + rowspan);
            if (!isInContainer(blankData,rowContainer)) {
              upstair.decreasRowSpanInDesign();
            }
          }
          blankType=blankData.getType();
        }
 else {
          upstair.setRowSpan(upstair.getRowSpan() + rowspan);
          if (!isInContainer(upstair,rowContainer)) {
            upstair.decreasRowSpanInDesign();
          }
        }
        int rowIndex=upstair.getRowIndex();
        for (int p=1; p <= rowspan; p++) {
          BlankData blank=new BlankData(upstair);
          blank.setRowIndex(rowIndex + p);
          blank.setType(blankType);
          cache.addData(currentColumnIndex,blank);
        }
      }
    }
 else     if (upstair.getRowSpanInDesign() > 0 && !isInContainer(upstair,rowContainer)) {
      upstair.decreasRowSpanInDesign();
    }
  }
}