[wp-hackers] possible small bug in widgets.php

[Aaron D. Campbell]

Or an array like array($someObject, 'someMethod') which still doesn't 
seem like it would have the recursion issue.

Otto wrote:
> Callback shouldn't be an object. It should be a function name.
> Basically, a string.
>
> -Otto
>
>
>
> On Mon, Feb 15, 2010 at 12:10 PM, Johannes Ruthenberg
> <tech at johannes-ruthenberg.de> wrote:
>   
>> Hi!
>>
>> There's a possible bug in wp-includes/widgets.php. Since I don't really
>> understand all the details I wanted to ask here what everyone else thinks
>> before opening a trac ticket.
>>
>> The bug was found in this discussion on the German WordPress forum:
>> http://forum.wordpress-deutschland.org/konfiguration/62484-error-bei-den-widgets.html
>>
>> A user got a PHP error when opening the backend widgets page: "Nesting level
>> too deep – recursive dependency" The error originates in widgets.php, in
>> function is_active_widget, what is now line 924.
>>
>> Apparently, you get this message in newer PHP versions (5.2+) when PHP
>> compares two objects with == instead ob ===. It compares all properties of
>> the objects, which can lead to a loop if the objects have circular
>> dependencies. Details for example here:
>> http://www.richardlord.net/blog/php-nesting-level-too-deep-recursive-dependency
>>
>> So, line 924 looks like this:
>>
>> if ( ( $callback && isset($wp_registered_widgets[$widget]['callback']) &&
>> $wp_registered_widgets[$widget]['callback'] == $callback ) || ( $id_base &&
>> _get_widget_id_base($widget) == $id_base ) ) {
>>
>> The second comparison should be harmless, that would always be a String. But
>> I'm not really sure what's inside
>> $wp_registered_widgets[$widget]['callback']. It seems to be an object which
>> can cause this problem, at least with some widgets. The poster in above
>> mentioned thread changed both comparisons to === and the PHP error vanished.
>> Of course, he doesn't want to change this with every WP upgrade, so I
>> promised to bring this to attention. ;-)
>>
>> So, do you think I should just open a trac ticket for this? Could the
>> stricter comparison have possible side effects? As I said, I'm not quite
>> sure what's actually compared there.
>>
>> Regards,
>> Johannes Ruthenberg
>>