Bug #70437 [Asn]: Changes to static properties in trait methods are not reflected in the class

Edit report at https://bugs.php.net/bug.php?id=70437&edit=1 ID: 70437 Updated by: bwoebi@php.net Reported by: davey@php.net Summary: Changes to static properties in trait methods are not reflected in the class Status: Assigned Type: Bug Package: Scripting Engine problem Operating System: OSX/Linux PHP Version: 7.0.0RC2 Assigned To: bwoebi Block user comment: N Private report: N New Comment: Is it by design? We don't know, it's neither documented nor mentioned in the original RFC. Heck, the RFC itself proposed even a singleton trait. With current semantics that trait could be used only exactly once, because the trait shares the static property. I guess that's not the purpose of traits, it's about horizontal *reuse*. Hence each class should have its own static properties and never use the static property of the trait. Also, by the way, if they were supposed to be independent, then the classes shouldn't be copied the traits static properties (and methods too) into them. We should have one or the other behavior, but having both behaviors is very confusing. Previous Comments: ------------------------------------------------------------------------ [2015-09-07 11:02:00] gron@php.net This is by design, changing that is a BC issue. The design is chosen based on the desired 'copy-down' semantics of traits. Static properties of traits are independent of the ones of classes using the trait. Changing it means you break the copy-down semantics by adding another corner case where it is not consistent. ------------------------------------------------------------------------ [2015-09-07 10:45:15] bwoebi@php.net Did you checkout the patch? It's always accessing the class' static property now as far as I see? ------------------------------------------------------------------------ [2015-09-07 10:39:25] davey@php.net The issue isn't when calling the method directly on the trait but also when calling it on the implementing class. Any changes to static properties within trait methods called on the implementing class are only reflected within the traits copy of it; rather than the implementing classes copy as it should be. ------------------------------------------------------------------------ [2015-09-07 09:15:15] bwoebi@php.net Totally agreeing with Nikita here; I've just attached a small PR: https://github.com/php/php-src/pull/1506 ------------------------------------------------------------------------ [2015-09-07 03:53:33] nikic@php.net Imho the bug here is that we allow calls to static methods on traits. I don't think that's supposed to work and we should add this forgotten check in PHP 7. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=70437 -- Edit this bug report at https://bugs.php.net/bug.php?id=70437&edit=1