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drupal/core 11.1

RemoveUpdaterPostInstallMethodsRector

Remove deprecated Updater::postInstall() and postInstallTasks() method overrides (drupal:11.1.0)

-class MyUpdater extends Updater { public function postInstallTasks() { return []; } }
+class MyUpdater extends Updater { }

Configure your rector.php:

<?php

use DrupalRector\Drupal11\Rector\Deprecation\RemoveUpdaterPostInstallMethodsRector;
use Rector\Config\RectorConfig;

return RectorConfig::configure()
    ->withRules([
        RemoveUpdaterPostInstallMethodsRector::class,
    ]);

Other rules in the drupal/core 11.1 set