Establish uninstall hook for undoing group_content_menu_update_9000()

That sub module and logic was only ever released in a dev branch. We have since removed that sub module.

I _think_ this can be cosed/wont-fix. But if someone disagrees, feel free to re-open.

I have an issue with the submodule menu_link_reference being removed in the 3.0.x branch. I understand that the dev-versions can have this kind of things happening and we shouldn't use them but at the moment there isn't other way to do it with Group v3.

So I tried to update to the latest dev-commit but I received error for the missing menu_link_reference module. I manually removed the dependency to the menu_link_reference submodule, then uninstalled it and updated group_content_menu to the latest dev-commit. Now I receive error "Drupal\Core\Entity\EntityStorageException: The "field_item:menu_link_reference" plugin does not exist.".

Any ideas what I could do without breaking the existing group content menus?

Let's add a post update that removes the field:

  $entity_definition_update_manager = \Drupal::entityDefinitionUpdateManager();
  if ($entity_definition_update_manager->getEntityType('group_content_menu') !== NULL) {
    $storage_definition = $entity_definition_update_manager->getFieldStorageDefinition('parent', 'group_content_menu');
    if ($storage_definition !== NULL) {
      $entity_definition_update_manager->uninstallFieldStorageDefinition($storage_definition);
    }
  }

Thanks @heddn that seems to fix the issue, although the problem is that I have to run it before updating to the latest dev-commit :D If there is other way to solve that would be nice but I can work with this I think.

Here are my steps that I needed to do, they are more complicated since these had to be done through deployments to couple of environments:

1. Create a patch with the post update hook posted by heddn at #5 and also include removal of dependency to menu_link_reference in group_content_menu.info.yml

2. Run patches but avoid updating module. Run update hook, uninstall menu_link_reference

3. Remove unneeded patches, update module

Oops didnt mean to change the status

Oops, I also had to re-add a dummy plugin too.

/**
 * Defines the 'menu_link_reference' field type.
 *
 * @FieldType(
 *   id = "menu_link_reference",
 *   label = @Translation("Menu link reference"),
 *   category = @Translation("General"),
 *   default_widget = "menu_link_reference",
 *   default_formatter = "string",
 *   no_ui = TRUE,
 * )
 */
final class MenuLinkReferenceItem extends FieldItemBase {}

It seems to get worse if you have data in the field. I'm not sure where the constraint comes from, because either of these can be NULL.

[error]  SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'parent_id' cannot be null: INSERT INTO "field_deleted_data_d0a1ee0c5e" ("bund
le", "entity_id", "revision_id", "langcode", "parent_menu_name", "parent_id", "deleted", "delta") SELECT "entity_table"."bundle" AS "bundle", "entity_t
able"."id" AS "entity_id", "entity_table"."id" AS "revision_id", "entity_table"."langcode" AS "langcode", "entity_table"."parent__menu_name" AS "parent
_menu_name", "entity_table"."parent__id" AS "parent_id", :deleted AS "deleted", :delta AS "delta"
> FROM
> "group_content_menu_field_data" "entity_table"
> WHERE ("entity_table"."parent__menu_name" IS NOT NULL) OR ("entity_table"."parent__id" IS NOT NULL) FOR UPDATE; Array
> (
>     [:deleted] => 1
>     [:delta] => 0
> )

Okay, I believe this patch does the trick. It combines the post_update hook and the fake plugins.

What it does not do, and I have not tested yet, is the bit phma mentions when there is content in the field already. I'll write another patch for that if necessary.