\Nette\Utils\DateTime::fromParts(2021,12,28) causing crash

[tprochazka]

Nette version: 3.0.8
PHP: 7.2.11 (I did not test the newer version, but Nette has 7.2 as the minimum supported version)
Czech localization system and setlocale(LC_ALL, 'cs_CZ');

\Nette\Utils\DateTime::fromParts(2021,12,28)

End with this exception:
DateTime::__construct(): Failed to parse time string (2021-12-28 00:00:0,00000) at position 23 (0): Unexpected character

I tried to change line

utils/src/Utils/DateTime.php

Line 77 in c77ecc3

$s = sprintf('%04d-%02d-%02d %02d:%02d:%02.5f', $year, $month, $day, $hour, $minute, $second);

to
$s = sprintf('%04d-%02d-%02d %02d:%02d:%02d', $year, $month, $day, $hour, $minute, $second);

And it works now.

Do we need microseconds there, if biggest possible entered value is 1s?

[milo]

Probably better fix is usage of %F which is non-locale aware.

[tprochazka]

Yes. This will also work. So it is caused by , instead of .
But I tested it and adding .000000 brings no difference in the result.
It anyway ends with

Nette\Utils\DateTime
date: '2021-12-28 00:00:00.000000'
timezone_type: 3
timezone: 'Europe/Prague'