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Privatization

PrivatizeFinalClassPropertyRector

Change property to private if possible

 final class SomeClass
 {
-    protected $value;
+    private $value;
 }

Configure your rector.php:

<?php

use Rector\Config\RectorConfig;
use Rector\Privatization\Rector\Property\PrivatizeFinalClassPropertyRector;

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

Other rules in the Privatization set