EntityDeleteForm.php

<?php

namespace Drupal\Core\Entity;

use Drupal\Core\Config\Entity\ConfigEntityInterface;
use Drupal\Core\Form\FormStateInterface;

/**
 * Provides a generic base class for an entity deletion form.
 *
 * @ingroup entity_api
 */
class EntityDeleteForm extends EntityConfirmFormBase {
    use EntityDeleteFormTrait;
    
    /**
     * {@inheritdoc}
     */
    public function buildForm(array $form, FormStateInterface $form_state) {
        $form = parent::buildForm($form, $form_state);
        $entity = $this->getEntity();
        // Only do dependency processing for configuration entities. Whilst it is
        // possible for a configuration entity to be dependent on a content entity,
        // these dependencies are soft and content delete permissions are often
        // given to more users. This method should not make assumptions that $entity
        // is a configuration entity in case we decide to remove the following
        // condition.
        if (!$entity instanceof ConfigEntityInterface) {
            return $form;
        }
        $this->addDependencyListsToForm($form, $entity->getConfigDependencyKey(), $this->getConfigNamesToDelete($entity), $this->getConfigManager(), $this->entityTypeManager);
        return $form;
    }
    
    /**
     * Gets the configuration manager.
     *
     * @return \Drupal\Core\Config\ConfigManager
     *   The configuration manager.
     */
    protected function getConfigManager() {
        return \Drupal::service('config.manager');
    }
    
    /**
     * Returns config names to delete for the deletion confirmation form.
     *
     * @param \Drupal\Core\Config\Entity\ConfigEntityInterface $entity
     *   The entity being deleted.
     *
     * @return string[]
     *   A list of configuration names that will be deleted by this form.
     */
    protected function getConfigNamesToDelete(ConfigEntityInterface $entity) {
        return [
            $entity->getConfigDependencyName(),
        ];
    }

}