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Configurable

PluginBaseIsConfigurableRector

Replaces deprecated PluginBase::isConfigurable() with instanceof ConfigurableInterface

-$this->isConfigurable()
+$this instanceof \Drupal\Component\Plugin\ConfigurableInterface

Configure your rector.php:

<?php

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

return RectorConfig::configure()
    ->withConfiguredRule(PluginBaseIsConfigurableRector::class, [
        new DrupalIntroducedVersionConfiguration('11.1.0'),
    ]);