When printing emoji characters from iOS device, output may be corrupt

Originator:preble
Number:rdar://31763683 Date Originated:4/21/2017
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 8.3.2
Classification: Reproducible:Always
 
Summary:
When using Swift.print() to log a string which includes emoji characters, sometimes the characters will be corrupted when displayed in the Xcode debug console (see screenshot).

Steps to Reproduce:
Create a fresh iOS app and simply call `print("◽️")` many times. Run on an iOS device.

Expected Results:
The emoji character should be represented correctly without escape sequences, one character per line.

Actual Results:
Some lines appear with multiple of the character, some with escape sequences showing.

Version:
Xcode 8.3.2 (8E2002), macOS 10.12.4 (16E195). Same problem occurred on Xcode 8.3.1.

Configuration:
In my testing this only occurs when running on an iOS device, not in the simulator, or in a macOS app. I tested it on an iPhone 6 running iOS 10.3.1 (14E304).

Comments


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