Using the dev version of the module and the patch for Support for sub-entity cloning @ https://www.drupal.org/project/entity_clone/issues/2706639 → we get the error "Fatal error: Maximum function nesting level of '256' reached, aborting!" when the entity has a Entity Reference field that references entities of the same content type.
The message also shows that it's looping around these functions
Drupal\entity_clone\EntityClone\Content\ContentEntityCloneFormBase->getRecursiveFormElement( ) .../ContentEntityCloneFormBase.php:89
Drupal\entity_clone\EntityClone\Content\ContentEntityCloneFormBase->getChildren( ) .../ContentEntityCloneFormBase.php:186
Drupal\entity_clone\EntityClone\Content\ContentEntityCloneFormBase->formElement( ) .../ContentEntityCloneFormBase.php:206
Drupal\entity_clone\EntityClone\Content\ContentEntityCloneFormBase->getRecursiveFormElement( ) .../ContentEntityCloneFormBase.php:89
Drupal\entity_clone\EntityClone\Content\ContentEntityCloneFormBase->getChildren( ) .../ContentEntityCloneFormBase.php:186
Drupal\entity_clone\EntityClone\Content\ContentEntityCloneFormBase->formElement( ) .../ContentEntityCloneFormBase.php:206
Seems that it's trying to clone entities within entities within entities which it probably shouldn't be doing.
Steps to duplicate:
1. Create a content type, save
2. Edit and add a Entity Reference field that references that same content type
3. Create a couple of nodes and edit and reference the other node
4. Try to clone and get this error
Not sure how to limit that recursive action or (right now) how to add the ability to not clone an Entity Reference field in the /admin/config/system/entity-clone settings page.
Fixed
1.0
Code
The change is currently missing an automated test that fails when run with the original code, and succeeds when the bug has been fixed.
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
I still go the error in the latest version of the module and in Drupal 9.5:
Fatal error: Allowed memory size of 671088640 bytes exhausted (tried to allocate 20480 bytes) in .../core/lib/Drupal/Core/Field/FieldItemBase.php on line 109