Core Data Save inside private context queue hangs when called from a global queue

Originator:thedov
Number:rdar://24107012 Date Originated:08-Jan-2016 10:21 AM
Status:Open Resolved:
Product:OS X SDK Product Version:iOS 9
Classification:Crash/Hang/Data Loss Reproducible:Always
 
Summary:
When attempting to save an NSManagedObjectContext using its own queue, but calling performBlock from a global queue, the save call never returns

Steps to Reproduce:
Run the attached playground

Expected Results:
Either the “save” call throws, or it prints:

a
b

Actual Results:
It prints:

a

Notes:
I first experienced this in the context of my actual code under development, from within a unit test. I condensed it into this reproducible playground

Comments


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