Symfony version(s) affected

4.4

Description

Hi!

On Symfony UX, we are seeing an error in substr_count() from simple=phpunit.php - https://github.com/symfony/ux/runs/4072355007?check_suite_focus=true

The issue originates from #43799 and is because we set SYMFONY_PHPUNIT_DIR: '/tmp/.phpunit' - so, a path that is outside of the project :).

Cheers!

How to reproduce

Run:

SYMFONY_PHPUNIT_DIR='/tmp/.phpunit' php vendor/symfony/phpunit-bridge/bin/simple-phpunit.php

Possible Solution

No response

Additional Context

No response