Open Radar

 
Summary:
When using Xcode playgrounds, sending simple AppleScript commands to Xcode results causes the playground to stop functioning

Steps to Reproduce:
1. Open a playground (e.g. the attached MyPlayground.playground).
2. Use the playground as usual.
3. Send AppleScript commands to Xcode, e.g.

tell application "Xcode"
	get file of front document whose name is "MyPlayground.playground"
end tell

(see CrashPlayground.scpt).

Expected Results:
The playground should continue to function as usual.

Actual Results:
The playground immediately shows an error message "Failed to launch process. The operation couldn't be completed. (Mach error -308 - ipc/mig server died)

After a while, modifying the playground does show updated results again, so I suspect that the connection does recover at some point. However, it should not crash in the first place.

The attachment includes log messages and a screenshot of the error.

Version:
Xcode 8.3.2 (8E2002)
macOS Sierra 10.12.4 (16E195)

Notes:
This problem has also been reported by other users: http://stackoverflow.com/questions/43072267/playgrounds-broken-in-xcode-8-3. In particular, http://stackoverflow.com/a/43627985 refers to the app Timing which works by sending AppleScript commands to applications.

Configuration:
2012 Retina MacBook Pro, running macOS Sierra 10.12.4

Attachments:
https://timingapp.com/download/CrashPlayground.zip