Use observe(func observe(_:options:changeHandler:) in performBackgroundTask gives weird result

Originator:hey.hgl
Number:rdar://32708841 Date Originated:June 12 2017
Status: Resolved:
Product:Core Data Product Version:
Classification: Reproducible:
 
If I use the new observe API in persistentContainer.performBackgroundTask, the closure will be called with very weird change value, and in the case I don't change the key path at all, the closure gets called too. Please see the provided test case.

Comments

The main part of the test case file contains this in application(_:didFinishLaunchingWithOptions:):

https://gist.github.com/anonymous/d933cd381a1fb2f7b2c78be4c4f1190a

Entity Foo contains a single attribute named "num" that is of the Double type

By hey.hgl at June 12, 2017, 10:35 a.m. (reply...)

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