src/Extension/Core/Type/ColumnType.php
public function configureOptions(OptionsResolver $resolver)
    {
        parent::configureOptions($resolver);

        $resolver->setDefault('parent_data_provider', null);
        $resolver->setAllowedTypes('parent_data_provider', ['Closure', 'null']);
    }
public function configureOptions(OptionsResolver $resolver)
    {
        parent::configureOptions($resolver);

        $resolver->setDefault('parent_data_provider', null);
        $resolver->setAllowedTypes('parent_data_provider', ['Closure', 'null']);
    }
{@inheritdoc}