From: alex dot dean at pni dot com
Operating system: Ubuntu GNU/Linux 2.6.15-27-386
PHP version: 5CVS-2007-01-23 (snap)
PHP Bug Type: Class/Object related
Bug description: signature mismatch for abstract/concrete method does not
produce a fatal error
Description:
------------
Given abstract and concrete versions of a class method, the first argument
is allowed to differ in its usage (or non-usage) of a default value. No
other arguments appear to be allowed to do this.
Reproduce code:
---------------
<?php
abstract class TheParent
{
abstract public function someMethod($argument1,$argument2);
}
class TheChild extends TheParent
{
public function someMethod($argument1='',$argument2)
{
return;
}
}
$test = new TheChild();
?>
Expected result:
----------------
I believe this should produce a fatal error, as the argument list for
TheChild::someMethod() does not match the argument list for
TheParent::someMethod().
Actual result:
--------------
In practice, this code executes without errors.
Additionally :
* If usage of default values do not match (abstract vs. concrete) for the
2nd argument, a fatal error is produced.
* If usage of default values do not match for the first argument (as in
the reproduce code), but there is matching usage of default values for the
2nd argument (add a default value to the abstract and concrete someMethod()
in the reproduce code), a fatal error is produced.
* Using a default value for the first argument of the abstract method,
and omitting a default argument from the first argument of the concrete
method, executes without errors.
For a single abstract/concrete method with 2 arguments, there are 16
possible combinations of usage of default arguments. I've tried all of
them by varying the argument list of the provided reproduce code, and
these are the only results that seem odd.
Apparently, the 1st argument to a method is allowed to differ from its
abstract definition in its usage of a default value, though no other
arguments are.
An addition to the Manual page on abstract methods indicating what
constitutes an identical method signature, especially in regards to
default arguments, would be very helpful.
--
Edit bug report at http://bugs.php.net/?id=40212&edit=1
--
Try a CVS snapshot (PHP 4.4):
http://bugs.php.net/fix.php?id=40212&r=trysnapshot44
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=40212&r=trysnapshot52
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=40212&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=40212&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=40212&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=40212&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=40212&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=40212&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=40212&r=support
Expected behavior: http://bugs.php.net/fix.php?id=40212&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=40212&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=40212&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=40212&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=40212&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=40212&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=40212&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=40212&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=40212&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=40212&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=40212&r=mysqlcfg
