Cell.php: Passing null to parameter #1 ($string) of type string is deprecated

[FFCZ]

This is:

- [x] a bug report

php 8.2.6 + PhpSpreadsheet 1.28.0
my project , recently upgraded php 7.4 to 8.4, frequent errors occur when reading excel, but not found in old php 7.4

warning tips:
vendor/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Cell/Cell.php
line: 393
msg: aa!N4 -> bb!O4 -> strtoupper(): Passing null to parameter #1 ($string) of type string is deprecated

It may be an adaptation issue to the new environment. hope can be compatible it. thank you!

What is the expected behavior?

What is the current behavior?

What are the steps to reproduce?

What features do you think are causing the issue

- [x] Reader

Does an issue affect all spreadsheet file formats? If not, which formats are affected?

Which versions of PhpSpreadsheet and PHP are affected?

[oleibman]

It would be helpful if you could upload the failing spreadsheet so that we can verify the problem and confirm that any fix that we make solves it.

[FFCZ]

tax.xlsx

[FFCZ]

The Excel file I used will generate the same error during the PHP 8.2.6 test.
Checking the official document, in PHP 8.1, 'Passing null to non nullable internal function parameters is deprecated.'.
https://www.php.net/releases/8.1/en.php
May be necessary to improve the relevant code, such as $aa? '' Or (string) $aa

$Reader = $path_info['extension'] === 'xls' ? new Xls() : new Xlsx();
$Spreadsheet = $Reader->load($op_file);
$sheet_num = $Spreadsheet->getSheetCount();
for ($i = 0; $i < $sheet_num; $i++) {
$Spreadsheet->setActiveSheetIndex($i);
$Spreadsheet->getActiveSheet()->getPageSetup()->setOrientation(PageSetup::ORIENTATION_LANDSCAPE);
$Spreadsheet->getActiveSheet()->getPageSetup()->setPaperSize(PageSetup::PAPERSIZE_A4);
$Spreadsheet->getActiveSheet()->getPageSetup()->setFitToWidth(1);
$Spreadsheet->getActiveSheet()->getPageSetup()->setFitToHeight(0);
$Spreadsheet->getActiveSheet()->getPageMargins()->setTop(0.39);
$Spreadsheet->getActiveSheet()->getPageMargins()->setRight(0.39);
$Spreadsheet->getActiveSheet()->getPageMargins()->setLeft(0.39);
$Spreadsheet->getActiveSheet()->getPageMargins()->setBottom(0.39);
}
$Writer = new \PhpOffice\PhpSpreadsheet\Writer\Xlsx($Spreadsheet);
$Writer->save($op_file2);
unset($Reader, $Writer);

[oleibman]

Thank you for the sample file. I am not sure what makes your spreadsheet so "special", but I definitely duplicate your problem.

[oleibman]

As a workaround, you should be able to avoid the error with:

$Writer->setPreCalculateFormulas(false);

In the meantime, there seem to be at least 2 different problems associated with your spreadsheet. The first, dealing with the null value, is easy to deal with, and I will probably have something ready in the next few days.

The other problem is that you have extremely complicated formulas, and the Calculation Engine, although it does not throw an exception, is unable to handle some of them correctly. I think it is likely that this inability is what is causing the unexpected null value to appear in the first place. Fixing that part of this problem is probably very difficult.

[FFCZ]

Thanks for your reply. The null issue was caused by a change in the new version of PHP.
And the formula is really a bit complicated. It is used by financial colleagues to calculate personal income tax.

[oleibman]

PR 3617 should eliminate the exceptions. It does not fix the incorrect internal calculations, which may or may not be adequate for your use case. I have used the debugging features available in PhpSpreadsheet, and cannot even see where it's going wrong, let alone how. Disabling branch pruning is a suggestion that has sometimes worked for Calculation problems, but it not only does not succeed here, it causes a new exception.