Bug #81497 [Nab]: Multiple traits can not be aliased since PHP 8.0

Edit report at https://bugs.php.net/bug.php?id=81497&edit=1 ID: 81497 Updated by: nikic@php.net Reported by: michael dot vorisek at email dot cz Summary: Multiple traits can not be aliased since PHP 8.0 Status: Not a bug Type: Bug Package: Scripting Engine problem Operating System: any PHP Version: 8.0.11 Block user comment: N Private report: N New Comment: Trait use blocks are meaningless. use ATrait { __isset as private __a_isset; } use BTrait { __isset as private __b_isset; } is equivalent to use ATrait, BTrait { __isset as private __a_isset; __isset as private __b_isset; } which is more obviously ambiguous. While your code was accepted prior to PHP 8, it did not actually do what you intended (it would create two aliases to ATrait::__isset instead.) Previous Comments: ------------------------------------------------------------------------ [2021-10-03 14:15:08] michael dot vorisek at email dot cz > The error message literally tells you what you need to do: > https://3v4l.org/lEgvo Thanks a lot!, why a trait name needs to be specified for the alias? I mean what is the logic behind, which ambiguity it solves? ------------------------------------------------------------------------ [2021-10-03 14:10:36] michael dot vorisek at email dot cz another failing test case https://3v4l.org/cUp5N ------------------------------------------------------------------------ [2021-10-03 14:04:57] nikic@php.net The error message literally tells you what you need to do: https://3v4l.org/lEgvo ------------------------------------------------------------------------ [2021-10-03 13:17:25] michael dot vorisek at email dot cz even one intermediate trait with alias is not enough https://3v4l.org/8gZrO the only supported solution for PHP 8.0 is to alias all traits inside a separate traits https://3v4l.org/hmnWC all 3 test cases should be supported ------------------------------------------------------------------------ [2021-10-03 13:00:10] michael dot vorisek at email dot cz Description: ------------ demo https://3v4l.org/eT0Aj (same as test case below) Test script: --------------- <?php trait ATrait { public function __isset(string $name): bool { return false; } } trait BTrait { public function __isset(string $name): bool { return false; } } class Model { use ATrait { __isset as private __a_isset; } use BTrait { __isset as private __b_isset; } public function __isset(string $name): bool { return false; } } Expected result: ---------------- no fatal error Actual result: -------------- Fatal error: An alias was defined for method __isset(), which exists in both ATrait and BTrait. Use ATrait::__isset or BTrait::__isset to resolve the ambiguity in /in/eT0Aj on line 17 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=81497&edit=1