Migrates from deprecated Form Builder->setDataMapper(new PropertyPathMapper()) to Builder->setDataMapper(new DataMapper(new PropertyPathAccessor()))
 use Symfony\Component\Form\Extension\Core\DataMapper\PropertyPathMapper;
 use Symfony\Component\Form\FormConfigBuilderInterface;
+use Symfony\Component\Form\Extension\Core\DataMapper\DataMapper;
+use Symfony\Component\Form\Extension\Core\DataAccessor\PropertyPathAccessor;
 class SomeClass
 {
     public function run(FormConfigBuilderInterface $builder)
     {
-        $builder->setDataMapper(new PropertyPathMapper());
+        $builder->setDataMapper(new DataMapper(new PropertyPathAccessor()));
     }
 }Configure your rector.php:
<?php
use Rector\Config\RectorConfig;
use Rector\Symfony\Symfony52\Rector\MethodCall\FormBuilderSetDataMapperRector;
return RectorConfig::configure()
    ->withRules([
        FormBuilderSetDataMapperRector::class,
    ]);