Edit report at http://bugs.php.net/bug.php?id=53727&edit=1
ID: 53727
Comment by: chris at cmbuckley dot co dot uk
Reported by: mattknight at xymail dot co dot uk
Summary: Inconsistent behavior of is_subclass_of with
interfaces
Status: Open
Type: Bug
Package: Class/Object related
Operating System: Gentoo x86_64
PHP Version: 5.3.5
Block user comment: N
Private report: N
New Comment:
Apologies; I actually meant:
false
true
false
true
Previous Comments:
------------------------------------------------------------------------
[2011-01-12 17:58:37] chris at cmbuckley dot co dot uk
One could argue that the expected result is actually:
true
true
false
false
since neither classes are technically "subclasses" of the interface.
Either way, the actual behaviour is undesirable :-)
------------------------------------------------------------------------
[2011-01-12 17:08:59] mattknight at xymail dot co dot uk
Description:
------------
is_subclass_of() can take a string as the first parameter, as well as a
second string parameter of the class name. It will check to see whether
a class with the name specified in the first parameter is a subclass of
the class with the name specified in the second parameter.
This logic, however, doesn't apply with interfaces.
The function behaves as expected for classes that don't directly
implement an interface, but won't recognise the interface on a class
that does directly implement it.
Test script:
---------------
<?php
interface MyInterface {
const TEST_CONSTANT = true;
}
class ParentClass implements MyInterface { }
class ChildClass extends ParentClass { }
echo (is_subclass_of('ChildClass', 'MyInterface') ? 'true' : 'false') .
"\n";
echo (defined('ChildClass::TEST_CONSTANT') ? 'true' : 'false') . "\n";
echo (is_subclass_of('ParentClass', 'MyInterface') ? 'true' : 'false') .
"\n";
echo (defined('ParentClass::TEST_CONSTANT') ? 'true' : 'false') . "\n";
Expected result:
----------------
true
true
true
true
Actual result:
--------------
true
true
false
true
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/bug.php?id=53727&edit=1
