[php-src] Issue #11725: ext-soap + Datetime + xsd:date = empty string

Issue: https://github.com/php/php-src/issues/11725 Author: Hanmac ### Description ext-soap should handle parsing and creating tags that are from type xsd:date or similar old PHP Bug about it: https://bugs.php.net/bug.php?id=44383 currently when you try to send a Datetime Object from php via soap, the send field is just empty without any exception what would be better: - if either it would better show an exception for types that can't be converted - it could handle the transformation from Datetime(Interface) into xsd:date itself My first try was this: ```php $typeMap = [ [ "type_ns" => "http://www.w3.org/2001/XMLSchema", "type_name" => "date", // xsd:date "to_xml" => [self::class, 'toXSDDate'] ] ]; public static function toXSDDate(?DateTimeInterface $dateTime): ?string { if (is_null($dateTime)) { return null; } return $dateTime->format(DateTimeInterface::ATOM); } ``` But that still doesn't work, because it is NOWHERE documented (or shown a warning or thrown an exception) that the to_xml callback explicit wants a string that somewhat looks like an xml, IMO that should have been better documented or shown as an example. ```php function static toXSDDate(?DateTimeInterface $dateTime) : ?string { if (is_null($dateTime)) { return null; } return '<value>' . $dateTime->format(DateTimeInterface::ATOM) . '</value>'; } ``` * The Bug is that it is silently ignored * The Feature would be to implement the conversion of DateTime objects * and the related Problem is that the handling of SOAP typemap isn't documented ### PHP Version PHP 8.2.6 ### Operating System _No response_