test1/public/drupal/core/modules/field/field.install

<?php

/**
 * @file
 * Install, update and uninstall functions for the field module.
 */

use Drupal\Core\Field\Plugin\Field\FieldType\EntityReferenceItem;

/**
 * Removes the stale 'target_bundle' storage setting on entity_reference fields.
 */
function field_update_8001() {
  $config = \Drupal::configFactory();
  /** @var \Drupal\Core\Field\FieldTypePluginManager $field_type_manager */
  $field_type_manager = \Drupal::service('plugin.manager.field.field_type');

  // Iterate on all fields storage.
  foreach ($config->listAll('field.storage.') as $field_id) {
    $field_storage = $config->getEditable($field_id);
    $class = $field_type_manager->getPluginClass($field_storage->get('type'));

    // Deal only with entity reference fields and descendants.
    if ($class == EntityReferenceItem::class || is_subclass_of($class, EntityReferenceItem::class)) {
      // Remove 'target_bundle' from settings.
      $field_storage->clear('settings.target_bundle')->save(TRUE);
    }
  }
}

/**
 * The 'entity_reference' field type is now provided by core.
 */
function field_update_8002() {
  $config_factory = \Drupal::configFactory();

  // Iterate on all configuration entities.
  foreach ($config_factory->listAll() as $id) {
    $changed = FALSE;
    $config = $config_factory->getEditable($id);

    // Update field storage configurations.
    if (strpos($id, 'field.storage.') === 0) {
      // Deal only with entity reference fields.
      if ($config->get('type') == 'entity_reference') {
        // Fix the type provider.
        $config->set('module', 'core');
        $changed = TRUE;
      }
    }

    // Remove entity_reference module dependency from any configuration entity.
    if ($dependencies = $config->get('dependencies.module')) {
      if (($delta = array_search('entity_reference', $dependencies)) !== FALSE) {
        unset($dependencies[$delta]);
        if ($dependencies) {
          $config->set('dependencies.module', array_values($dependencies));
        }
        else {
          $config->clear('dependencies.module');
        }
        $changed = TRUE;
      }
    }

    if ($changed) {
      $config->save(TRUE);
    }
  }
}

/**
 * Populate the new 'auto_create_bundle' setting for entity reference fields.
 */
function field_update_8003() {
  $config = \Drupal::configFactory();
  /** @var \Drupal\Core\Field\FieldTypePluginManager $field_type_manager */
  $field_type_manager = \Drupal::service('plugin.manager.field.field_type');

  // Iterate over all fields.
  foreach ($config->listAll('field.field.') as $field_id) {
    $field = $config->getEditable($field_id);
    $class = $field_type_manager->getPluginClass($field->get('field_type'));

    // Deal only with entity reference fields and descendants.
    if ($class == EntityReferenceItem::class || is_subclass_of($class, EntityReferenceItem::class)) {
      $handler_settings = $field->get('settings.handler_settings');

      if (is_array($handler_settings) && !empty($handler_settings['auto_create'])) {
        // If the field can reference multiple bundles, pick the first one
        // available in order to replicate the previous behavior.
        if (is_array($handler_settings['target_bundles']) && count($handler_settings['target_bundles']) > 1) {
          $handler_settings['auto_create_bundle'] = reset($handler_settings['target_bundles']);
        }
        // Otherwise, we don't know which bundle to use for auto-creation so we
        // have to disable the functionality completely.
        elseif (!$handler_settings['target_bundles']) {
          $handler_settings['auto_create'] = FALSE;
          $handler_settings['auto_create_bundle'] = NULL;
        }
      }

      $field->set('settings.handler_settings', $handler_settings)->save(TRUE);
    }
  }
}