ReadOnlyAnonymousClassRector

Decorate read-only anonymous class with readonly attribute

-new class
+new readonly class
 {
     public function __construct(
-        private readonly string $name
+        private string $name
     ) {
     }
 };

Configure your rector.php:

<?php

use Rector\Config\RectorConfig;
use Rector\Php83\Rector\Class_\ReadOnlyAnonymousClassRector;

return RectorConfig::configure()
    ->withRules([
        ReadOnlyAnonymousClassRector::class,
    ]);
SETS:  PHP 8.3