ReflectionFunction::getClosureUsedVariables() returns empty array in presence of variadic arguments

[fabio-ivona]

Description

It seems that when using a ReflectionFunction method getClosureUsedVariables() to retrieve its use variables, when the closure has a variadic argument, getClosureUsedVariables() returns an empty array

it can be reproduced (both in PHP8.1 and PHP8.2) by running this simple snipped

$data = 1;
$closure = function($var) use($data){};
var_dump((new ReflectionFunction($closure))->getClosureUsedVariables());

$closure = function($var, ...$variadic) use($data){};
var_dump((new ReflectionFunction($closure))->getClosureUsedVariables());

Resulted in this output:

array(1) {
  ["data"] => int(1)
}
array(0) {
}

But I expected this output instead:

array(1) {
  ["data"] => int(1)
}
array(0) {
  ["data"] => int(1)
}

PHP Version

PHP 8.2.2 (also in PHP 8.1.15 as well)

Operating System

tested in Ubuntu 20.04, 21.04 and alpine

Example snippet

https://onlinephp.io/c/1fd54

[nielsdos]

Looks like it's implemented by reading the oplines, and I see that it explicitly uses num_args and BIND_STATIC (but no RECV_VARIADIC?), so I guess one of those two is where the problem lies. I'll try to look at this today.

[nielsdos]

I think I fixed it locally by checking the ZEND_ACC_VARIADIC flag, and moving one opline forward to skip the RECV_VARIADIC. I'll check it to be sure, write a test and PR this up.

[fabio-ivona]

Great! Thanks @nielsdos !