RectorPHP breaks with PHPStan 2.1.34

[michaljusiega]

Bug Report

Subject	Details
Rector version	2.3.1
PHPStan version	2.1.34
PHP	8.5.2

Hello!

Today (2026-01-19) was released PHPStan version 2.1.34 (see https://github.com/phpstan/phpstan/releases/tag/2.1.34)
But it's breaks a comptability with rector throws a weird issue (and also throws deprecations).

Minimal PHP Code Causing Issue

Just add to composer.json a two components:

{
        "phpstan/phpstan": "2.1.33",
        "rector/rector": "2.3.1"
 }

and run dry-run on rector process

root@0e1d192c3a98:/var/www/smarthome# php -dxdebug.mode=off /var/www/smarthome/vendor/bin/rector process --dry-run --config=/var/www/smarthome/rector.php /var/www/smarthome/src /var/www/smarthome/tests

Warning: Undefined array key 0 in /var/www/smarthome/vendor/rector/rector/src/DependencyInjection/PHPStan/PHPStanContainerMemento.php on line 35

Deprecated: Using null as an array offset is deprecated, use an empty string instead in /var/www/smarthome/vendor/rector/rector/src/DependencyInjection/PHPStan/PHPStanContainerMemento.php on line 35

Warning: Undefined array key 0 in /var/www/smarthome/vendor/rector/rector/src/DependencyInjection/PHPStan/PHPStanContainerMemento.php on line 35

Deprecated: Using null as an array offset is deprecated, use an empty string instead in /var/www/smarthome/vendor/rector/rector/src/DependencyInjection/PHPStan/PHPStanContainerMemento.php on line 35


  16/821 [░░░░░░░░░░░░░░░░░░░░░░░░░░░░]   1%Fatal error: Uncaught Error: Typed property RectorPrefix202601\Symplify\EasyParallel\ValueObject\ParallelProcess::$encoder must not be accessed before initialization in /var/www/smarthome/vendor/rector/rector/vendor/symplify/easy-parallel/src/ValueObject/ParallelProcess.php:108
Stack trace:
#0 /var/www/smarthome/vendor/rector/rector/vendor/symplify/easy-parallel/src/ValueObject/ProcessPool.php(48): RectorPrefix202601\Symplify\EasyParallel\ValueObject\ParallelProcess->quit()
#1 /var/www/smarthome/vendor/rector/rector/vendor/symplify/easy-parallel/src/ValueObject/ProcessPool.php(58): RectorPrefix202601\Symplify\EasyParallel\ValueObject\ProcessPool->quitProcess('qjmavxs8e8')
#2 /var/www/smarthome/vendor/rector/rector/src/Parallel/Application/ParallelFileProcessor.php(146): RectorPrefix202601\Symplify\EasyParallel\ValueObject\ProcessPool->quitAll()
#3 /var/www/smarthome/vendor/rector/rector/vendor/symplify/easy-parallel/src/ValueObject/ParallelProcess.php(118): Rector\Parallel\Application\ParallelFileProcessor->{closure:{closure:Rector\Parallel\Application\ParallelFileProcessor::process():115}:122}(Array)
#4 /var/www/smarthome/vendor/rector/rector/vendor/evenement/evenement/src/EventEmitterTrait.php(111): RectorPrefix202601\Symplify\EasyParallel\ValueObject\ParallelProcess->{closure:RectorPrefix202601\Symplify\EasyParallel\ValueObject\ParallelProcess::bindConnection():112}(Array)
#5 /var/www/smarthome/vendor/rector/rector/vendor/clue/ndjson-react/src/Decoder.php(117): RectorPrefix202601\Evenement\EventEmitter->emit('data', Array)
#6 /var/www/smarthome/vendor/rector/rector/vendor/evenement/evenement/src/EventEmitterTrait.php(111): RectorPrefix202601\Clue\React\NDJson\Decoder->handleData(Array)
#7 /var/www/smarthome/vendor/rector/rector/vendor/react/stream/src/Util.php(62): RectorPrefix202601\Evenement\EventEmitter->emit('data', Array)
#8 /var/www/smarthome/vendor/rector/rector/vendor/evenement/evenement/src/EventEmitterTrait.php(111): RectorPrefix202601\React\Stream\Util::{closure:RectorPrefix202601\React\Stream\Util::forwardEvents():61}('{"action":"resu...')
#9 /var/www/smarthome/vendor/rector/rector/vendor/react/stream/src/DuplexResourceStream.php(168): RectorPrefix202601\Evenement\EventEmitter->emit('data', Array)
#10 /var/www/smarthome/vendor/rector/rector/vendor/react/event-loop/src/StreamSelectLoop.php(201): RectorPrefix202601\React\Stream\DuplexResourceStream->handleData(Resource id #3465)
#11 /var/www/smarthome/vendor/rector/rector/vendor/react/event-loop/src/StreamSelectLoop.php(173): RectorPrefix202601\React\EventLoop\StreamSelectLoop->waitForStreamActivity(2776)
#12 /var/www/smarthome/vendor/rector/rector/src/Parallel/Application/ParallelFileProcessor.php(185): RectorPrefix202601\React\EventLoop\StreamSelectLoop->run()
#13 /var/www/smarthome/vendor/rector/rector/src/Application/ApplicationFileProcessor.php(234): Rector\Parallel\Application\ParallelFileProcessor->process(Object(RectorPrefix202601\Symplify\EasyParallel\ValueObject\Schedule), '/var/www/smarth...', Object(Closure), Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput))
#14 /var/www/smarthome/vendor/rector/rector/src/Application/ApplicationFileProcessor.php(126): Rector\Application\ApplicationFileProcessor->runParallel(Array, Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput), Object(Closure))
#15 /var/www/smarthome/vendor/rector/rector/src/Console/Command/ProcessCommand.php(182): Rector\Application\ApplicationFileProcessor->run(Object(Rector\ValueObject\Configuration), Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput))
#16 /var/www/smarthome/vendor/rector/rector/vendor/symfony/console/Command/Command.php(289): Rector\Console\Command\ProcessCommand->execute(Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput), Object(RectorPrefix202601\Symfony\Component\Console\Output\ConsoleOutput))
#17 /var/www/smarthome/vendor/rector/rector/vendor/symfony/console/Application.php(899): RectorPrefix202601\Symfony\Component\Console\Command\Command->run(Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput), Object(RectorPrefix202601\Symfony\Component\Console\Output\ConsoleOutput))
#18 /var/www/smarthome/vendor/rector/rector/vendor/symfony/console/Application.php(279): RectorPrefix202601\Symfony\Component\Console\Application->doRunCommand(Object(Rector\Console\Command\ProcessCommand), Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput), Object(RectorPrefix202601\Symfony\Component\Console\Output\ConsoleOutput))
#19 /var/www/smarthome/vendor/rector/rector/src/Console/ConsoleApplication.php(60): RectorPrefix202601\Symfony\Component\Console\Application->doRun(Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput), Object(RectorPrefix202601\Symfony\Component\Console\Output\ConsoleOutput))
#20 /var/www/smarthome/vendor/rector/rector/vendor/symfony/console/Application.php(162): Rector\Console\ConsoleApplication->doRun(Object(RectorPrefix202601\Symfony\Component\Console\Input\ArgvInput), Object(RectorPrefix202601\Symfony\Component\Console\Output\ConsoleOutput))
#21 /var/www/smarthome/vendor/rector/rector/bin/rector.php(130): RectorPrefix202601\Symfony\Component\Console\Application->run()
#22 /var/www/smarthome/vendor/rector/rector/bin/rector(5): require_once('/var/www/smarth...')
#23 /var/www/smarthome/vendor/bin/rector(119): include('/var/www/smarth...')
#24 {main}
  thrown in /var/www/smarthome/vendor/rector/rector/vendor/symplify/easy-parallel/src/ValueObject/ParallelProcess.php on line 108

Downgrading/blocks to 2.1.33 PHPStan works for me.

Expected Behaviour

Process of rector dry-run or fixer should be successfully.

[samsonasik]

I am aware of that, I created PR:

• Bump to PHPStan 2.1.34 and fix compatible code rector-src#7844

for it.

[michaljusiega]

Thank you for fast response @samsonasik !

[samsonasik]

Rector 2.3.2 released for it :)

https://github.com/rectorphp/rector/releases/tag/2.3.2

[michaljusiega]

Thank you!

[github-actions]

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