Bug #79925 [Com]: Magic method __set_state signature check does not support covariance

Edit report at https://bugs.php.net/bug.php?id=79925&edit=1 ID: 79925 Comment by: ondrej at mirtes dot cz Reported by: ondrej at mirtes dot cz Summary: Magic method __set_state signature check does not support covariance Status: Verified Type: Bug Package: Class/Object related Operating System: All PHP Version: 8.0Git-2020-08-02 (Git) Block user comment: N Private report: N New Comment: *contravariance Previous Comments: ------------------------------------------------------------------------ [2020-08-03 07:16:31] ondrej at mirtes dot cz Looks like the parameter types should also be given some care, I tried to see if they support covariance and so far it looks like they're not enforced at all: public static function __set_state(int $properties): object leads to no error on 3v4l. This also doesn't but I expect that: public static function __set_state(mixed $properties): object ------------------------------------------------------------------------ [2020-08-02 21:35:54] ondrej at mirtes dot cz Description: ------------ Magic methods from this RFC https://wiki.php.net/rfc/magic-methods-signature should support covariance but don't. You should be able to narrow down a return type but currently can't. Test script: --------------- <?php class Foo { /** * @param mixed[] $properties * @return Type */ public static function __set_state(array $properties): self { return new self(); } } Expected result: ---------------- nothing Actual result: -------------- Fatal error: Foo::__set_state(): Return type must be object when declared in... ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79925&edit=1