Open Radar

 
Summary:
Two apps on the same device should be able to access a common ubiquity container using file coordination. In practice one app is blocked forever on accessing the container directory.

Steps to Reproduce:
The attached project replicates the problem. It contains two targets which only differ in bundle ID and display name, so two copies of the app can be installed on the same device.

When a single copy is installed, or copies installed on two devices, "documents" (which are directories) can be created and deleted, and files inside those directories can be created and deleted. No NSMetadataQuery is implemented, so manual refreshes are required.

When two instances of the app are installed on the same device, however, and both are running, opening a document directory results in a failure of the file coordination at -[NGModel scanContents:withCompletion:], with the timer eventually cancelling the file coordination.

Expected Results:
Because the two apps share a ubiquity container and use coordinated file access, they should be able to share data successfully.

Actual Results:
If both apps are running, one instance is prevented from scanning a container directory in the ubiquity container.

Regression:
Unknown.

Notes:
Demonstration project at http://d.pr/f/Qjtn