Open Radar

 
[Note, this has been edited pretty heavily from the actual bug report due to confidentiality issues.]


Summary:

Managed objects synced via iCloud have the wrong entity.


Steps to Reproduce:

Build an app that uses Core Data's built in iCloud syncing. Then create some data on one Mac, and inspect the results received on a different Mac.


Expected Results:

Objects created on one Mac would appear on the other Mac with the same Core Data entity as the one used to create the object.


Actual Results:

Frequently, the following (for my data model, at least):

1. Create an object on Mac A using entity ItemType1
2. Receive an object on Mac B with the same attributes and relationships, but which is an instance of entity ItemType2.

In my case I can verify that it's the same instance because the entity has a field that stores a string representation of a UUID. It also has a "type" field that tells me which item type it's supposed to be. By comparing UUIDs and "type", I can verify that the received object is the same as the one created and that it should be an instance of ItemType1.

This does not affect every instance of ItemType1. I have not been able to detect a pattern that correlates the problem with any attributes of the affected instances.

Regression:

None, but FWIW both Macs are running 10.8.2.

Notes:

Perhaps not coincidentally, both ItemType1 and ItemType2 inherit from the same abstract parent entity (FooItem) which in turn inherits from another abstract parent entity (AbstractItem).