- var_dump: documentation ( source)
<?php
$d1 = new \DateTimeImmutable('today 00:00', new \DateTimeZone('Europe/Prague'));
$d2 = new \DateTimeImmutable('tomorrow 00:00', new \DateTimeZone('Europe/London'));
var_dump($d1->diff($d2)->format('%yy,%mm,%dd,%hh,%im,%ss'));