FinalizeTestCaseClassRector

Find another rule

Make PHPUnit test case final

 use PHPUnit\Framework\TestCase;

-class SomeClass extends TestCase
+final class SomeClass extends TestCase
 {
 }

Configure your rector.php:

<?php

use Rector\Config\RectorConfig;
use Rector\Privatization\Rector\Class_\FinalizeTestCaseClassRector;

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