Bug #76973 [Com]: Return type that is alias of base class' type should be compatible
Edit report at https://bugs.php.net/bug.php?id=76973&edit=1
ID: 76973
Comment by: spam2 at rhsoft dot net
Reported by: ayg at aryeh dot name
Summary: Return type that is alias of base class' type should
be compatible
Status: Assigned
Type: Bug
Package: Scripting Engine problem
Operating System: Ubuntu
PHP Version: 7.2.10
Assigned To: levim
Block user comment: N
Private report: N
New Comment:
rude is such a unreadable sample - code in a style of "} }" is pure effrontery
Previous Comments:
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[2018-10-04 18:01:59] nikic@php.net
Long term this is going to be implicitly solved by proper variance support, but for now it might
make sense to handle this the same way we do for argument types, i.e. load the classes if they do
not pass the string equality checks, but only allow exact matches (no variance).
@levim: What do you think about this?
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[2018-10-04 17:59:15] nikic@php.net
Comment by spam2 at rhsoft dot net deleted. It was rude, without contributing technical insight wrt
this issue.
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[2018-10-04 17:26:14] ayg at aryeh dot name
Description:
------------
If a base class defines a method with a return type declaration, and a derived class overrides the
method, the return type in the derived class must be the same as in the base class. However, if the
return types are classes that are aliases of one another, it should be considered the same.
Currently it is not.
Test script:
---------------
<?php
class A {}
class_alias( "A", "B" );
class C { function f() : A { return new A; } }
class D extends C { function f() : B { return new B; } }
Expected result:
----------------
No error
Actual result:
--------------
PHP Fatal error: Declaration of D::f(): B must be compatible with C::f(): A in Standard input code
on line 5
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Edit this bug report at https://bugs.php.net/bug.php?id=76973&edit=1
Thread (7 messages)