Everything

php

Nasty Parser Bug

php.internals

Sterling Hughes

23 years ago

Hey,

Bug 24441 (http://bugs.php.net/bug.php?id=24441), displays the following
problem:

<?php
class test {
var $filter = 'hello';
var $array = array('hello', 'hello world', 'hey there');

function test() {
array_filter($this->array, array($this, 'filter'));
}

function filter ($value) {
return preg_match("/{$this->filter}/i", $value);
}
}
$t = new test;
var_dump($t->filter('hello world'));
?>

That script (also attached), will give an error:

Fatal error: Using $this when not in object context in
/data/home/sterling/work/os/php/php-src/arraybug.php on line 11

If you comment out the test() function declaration, everything will work
as expected.

-Sterling

--
"First they ignore you, then they laugh at you,
then they fight you, then you win."
- Gandhi

Timm Friebe

23 years ago

On Wed, 2003-07-02 at 06:34, Sterling Hughes wrote:
[...]

> $t = new test;
> var_dump($t->filter('hello world'));

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Changing this line to:
var_dump(call_user_func(array($t, 'filter'), 'hello world'));

or even
$t= new Reflection_Method('test', 'filter');
var_dump($t->invoke(new test(), 'hello world'));

yields the same bug.

ZE1 outputs "int(1)". ZE2 does so, too, if I rename "test" to anything
else (except "__construct", which causes the same problem).

The same problem arises for other array functions such as usort,
array_map etc., but _not_ for call_user_func(_array).

After short investigation it looks like all of these use
fast_call_user_function() but do not pass an object_pp. Either this
should be patched in ext/standard/array.c or fast_call_user_function
shoud check for the callback being an array($obj, $func) / array($class,
$func) *even* when a function pointer is passed.

- Timm

Sterling Hughes

23 years ago

On Wed, 2003-07-02 at 10:11, Timm Friebe wrote:

> On Wed, 2003-07-02 at 06:34, Sterling Hughes wrote:
> [...]
> > $t = new test;
> > var_dump($t->filter('hello world'));
>   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>   Changing this line to:
>     var_dump(call_user_func(array($t, 'filter'), 'hello world'));
>
>   or even
>     $t= new Reflection_Method('test', 'filter');
>     var_dump($t->invoke(new test(), 'hello world'));
>
>   yields the same bug.
>
> ZE1 outputs "int(1)". ZE2 does so, too, if I rename "test" to anything
> else (except "__construct", which causes the same problem).
>
> The same problem arises for other array functions such as usort,
> array_map etc., but _not_ for call_user_func(_array).
>
> After short investigation it looks like all of these use
> fast_call_user_function() but do not pass an object_pp. Either this
> should be patched in ext/standard/array.c or fast_call_user_function
> shoud check for the callback being an array($obj, $func) / array($class,
> $func) *even* when a function pointer is passed.

Then why would it work if test() is undefined?  Further, why would it
work when no array functions are used (as with my original example).  I
think you might be right that this is a separate bug, but its certainly
not the same bug that I'm talking about.

-Sterling

>
> - Timm

--
"Nothing is particularly hard if you divide it into small jobs."
- Henry Ford