[Xcode 7.1.1] Second assistant editor always gets stuck in an infinite non-deterministic layout loop

Originator:info
Number:rdar://23620751 Date Originated:19-Nov-2015 03:41 PM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 7.1.1
Classification:UI/Usability Reproducible:Always
 
Summary:
Opening more than 1 assistant editor always makes Xcode freeze, as it gets stuck in an infinite layout loop.

Steps to Reproduce:
- Open an Xcode project.
- Select View -> Assistant Editor -> All Editors Stacked Horizontally
- Open the assistant editor.
- Tap on the “+” button to open a second editor.

Expected Results:
- The 3rd column is displayed and Xcode is usable.

Actual Results:
- Xcode is completely unusable, the layout is stuck laying out, changing the width of the last column +- 1px (see attached video).

Regression:
I think the first time I saw this was Xcode 7.0.

Comments


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