[Bug] CsvCell.setCellValue(Calendar) silently writes an empty field

[Aias00]

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Fesod version

current main (50a6b5b)

JDK version

Temurin 25 (code path is version-independent, affects 8+)

Operating system

Linux (not OS-specific)

Steps To Reproduce

Writing a Calendar value to a CsvCell via the POI Cell API silently produces an empty field instead of the date.

Calendar cal = Calendar.getInstance();
cal.set(2024, Calendar.JANUARY, 15, 12, 30, 45);
cal.set(Calendar.MILLISECOND, 0);

try (Writer writer = Files.newBufferedWriter(csvFile.toPath(), StandardCharsets.UTF_8)) {
    CsvWorkbook workbook = new CsvWorkbook(writer, null, false, false, StandardCharsets.UTF_8, false);
    CsvSheet sheet = (CsvSheet) workbook.createSheet();
    CsvRow row = (CsvRow) sheet.createRow(0);

    Cell cell = row.createCell(0, CellType.NUMERIC);
    cell.setCellValue(cal);

    sheet.close();
}

// csvFile content is an empty field instead of "2024-01-15 12:30:45"

Current Behavior

The CSV cell is written as an empty field. The Calendar value is silently lost — no exception is thrown.

Expected Behavior

The cell should be written as a date (2024-01-15 12:30:45 by default), the same way setCellValue(java.util.Date) and setCellValue(java.time.LocalDateTime) behave on a CsvCell.

Anything else?

Root cause: CsvCell.setCellValueImpl(Calendar) sets dateValue and cellType = NUMERIC but, unlike its sibling setters, does not set numericCellType = NumericCellTypeEnum.DATE:

https://github.com/apache/fesod/blob/main/fesod-sheet/src/main/java/org/apache/fesod/sheet/metadata/csv/CsvCell.java#L186-L193

@Override
protected void setCellValueImpl(Calendar value) {
    if (value == null) {
        return;
    }
    this.dateValue = LocalDateTime.ofInstant(value.toInstant(), ZoneId.systemDefault());
    this.cellType = CellType.NUMERIC;
    // missing: this.numericCellType = NumericCellTypeEnum.DATE;
}

The sibling Date setter (a few lines above) and LocalDateTime setter both set it:

this.cellType = CellType.NUMERIC;
this.numericCellType = NumericCellTypeEnum.DATE;

In CsvSheet.buildCellValue the NUMERIC branch dispatches on csvCell.getNumericCellType() == NumericCellTypeEnum.DATE; when it is not set, the cell takes the number branch, finds numberValue is null, and returns null, producing an empty field.

Adding the missing line fixes it:

this.numericCellType = NumericCellTypeEnum.DATE;

Are you willing to submit a PR?

• I'm willing to submit a PR!