Bug #71414 [Opn->Csd]: Fatal error when using interface trait and inheritance

Edit report at https://bugs.php.net/bug.php?id=71414&edit=1 ID: 71414 Updated by: krakjoe@php.net Reported by: krzysiekpiasecki at gmail dot com Summary: Fatal error when using interface trait and inheritance -Status: Open +Status: Closed Type: Bug Package: Class/Object related Operating System: OS X 10.9.5 PHP Version: 7.0.2 Block user comment: N Private report: N New Comment: Automatic comment on behalf of krakjoe Revision: http://git.php.net/?p=php-src.git;a=commit;h=4327370d1308eab3c611fc6994e67048a18f92ef Log: fix #71414 (Interface method override inherited method and implemented in a trait causes fatal error) Previous Comments: ------------------------------------------------------------------------ [2016-01-19 22:41:53] requinix@php.net Oh, I see what you mean. The trait's method should overwrite the inherited method, and since stuff like https://3v4l.org/dCZ9h works without the trait, using the trait should also be allowed. ------------------------------------------------------------------------ [2016-01-19 22:24:26] krzysiekpiasecki at gmail dot com I wrote, that method Y in TraitY is well defined and it is according to InterfaceY No fatal error when method public y():string is defined in the class body not only in a trait. What's the difference? class Y extends X implements InterfaceY { use TraitY; public function y(): string { } } ------------------------------------------------------------------------ [2016-01-19 21:18:19] requinix@php.net It is not "well defined": X's y() must also have the string return type declaration to be compatible. https://wiki.php.net/rfc/return_types https://3v4l.org/lG7t4 ------------------------------------------------------------------------ [2016-01-19 19:16:31] krzysiekpiasecki at gmail dot com Description: ------------ Interface method override inherited method and implemented in a trait causes fatal error Test script: --------------- interface InterfaceY { public function y(): string; } trait TraitY { public function y(): string { } } class X { public function y() { } } class Y extends X implements InterfaceY { use TraitY; } Expected result: ---------------- No fatal error. Method Y in TraitY is well defined Actual result: -------------- Fatal error: Declaration of X::y() must be compatible with Y::y(): string PS __No fatal error__ when: class Y extends X implements InterfaceY { use TraitY; public function y(): string { } } ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=71414&edit=1