Anonymous class reference in trigger_error / thrown Exception

[henzeb]

Description

The following code is a bug since the introduction of anonymous classes in PHP 7.0:

https://3v4l.org/0OTZ9#v7.0.0 // for reference
https://3v4l.org/0OTZ9#v8.3.1

<?php

$anonymous = new class(){};

echo get_class($anonymous).': now you see me...';

trigger_error(
    get_class($anonymous).' ...now you don\'t!', 
    E_USER_ERROR
);

Note: it doesn't matter if get_class or $anonymous::class is used. As soon as it is an anonymous class name, it fails.

It also fails when throwing an Exception:

<?php

$anonymous = new class(){};

echo get_class($anonymous).': now you see me...';

throw new Exception(
    get_class($anonymous).' ...now you don\'t!', 
    E_USER_ERROR
);

Resulted in this output:

class@anonymous/in/0OTZ9:3$0: now you see me...
Fatal error: class@anonymous in /in/0OTZ9 on line 7

Process exited with code 255.

But I expected this output instead:

class@anonymous/in/0OTZ9:3$0: now you see me...
Fatal error: class@anonymous ... now you don't in /in/0OTZ9 on line 7

Process exited with code 255.

PHP Version

PHP 8.3.1

Operating System

No response

[iluuu1994]

Anonymous classes contain a non printable \0 character. trigger_error apparently ignores the message length and as such misses the latter half of the message.

[henzeb]

I guess a workaround would be:

preg_replace('/[\x00]/', '',$class::class);

[iluuu1994]

I quickly had a look yesterday, but we're relying on some API that doesn't support \0 in messages, which is annoying (printf etc).

[nielsdos]

This seems to work: https://gist.github.com/nielsdos/79419e56941ae80062e1b382c7e275f9
But I didn't test that very thoroughly, also there are two remaining issues:

• One related to syslog (marked with XXX)
• The compiler gives warnings because the format attribute is used on the Zend's print-family functions and the compiler doesn't know about the %Z format that we implement

[iluuu1994]

The fix looks correct to me, although tbh I'm not sure it's worthwhile. For %Z, the _unchecked variants of these functions should be used. Also a nit: I think for fwrite, size and nmemb are supposed to be reversed.

[nielsdos]

The fix looks correct to me, although tbh I'm not sure it's worthwhile.

Idk either, I don't like the complication.

For %Z, the _unchecked variants of these functions should be used.

TIL, thx

Also a nit: I think for fwrite, size and nmemb are supposed to be reversed.

Hm indeed, confusing function and confusing naming.

[bwoebi]

I would like to see this fixed as well, it's definitely weird and buggy to see error messages cut-off. From the perspective of a PHP user \0 isn't really special.

[iluuu1994]

I don't object to fixing this. @nielsdos Feel free to create a PR.