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Configurable

ErrorCurrentErrorHandlerRector

Replace deprecated \Drupal\Core\Utility\Error::currentErrorHandler() with PHP built-in get_error_handler()

-$handler = \Drupal\Core\Utility\Error::currentErrorHandler();
+$handler = get_error_handler();

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\ErrorCurrentErrorHandlerRector;
use DrupalRector\Rector\ValueObject\DrupalIntroducedVersionConfiguration;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withConfiguredRule(ErrorCurrentErrorHandlerRector::class, [
        new DrupalIntroducedVersionConfiguration('11.3.0'),
    ]);