Bug report

PHPStan believes that DatePeriod::getEndDate will always return a DateTimeInterface object while it can also return null if no end date can be computed from the DatePeriod constructor input see https://www.php.net/manual/en/dateperiod.getenddate.php

Code snippet that reproduces the problem

https://phpstan.org/r/93804099-9892-4e17-a54e-6b9b8d18be62

and

https://3v4l.org/qBgdp

Expected output

Expect no error to be display