Open Radar

 
Summary:
On iCloud Drive, you can only move a file into an app’s folder if the app declares the type as supported.

With UIDocumentBrowserViewController (and the Files app) you can’t see in advance whether an app folder supports the type of file being moved/copied. You have to tap the app folder first then see if the confirm button becomes disabled.

Steps to Reproduce:
1. Open PDF Viewer (https://itunes.apple.com/app/pdf-viewer-read-review-annotate/id1120099014?mt=8) or the Files app and find a file somewhere
2. Tap Select in the top right
3. Tap a file (for example, a Numbers document)
4. Tap Move at the bottom
5. Navigate to iCloud Drive and an app folder that does not support that type of file (for example, Pages for the Numbers document)

Expected Results:
That the unsupported folder should be disabled visually (grey text) and tapping it should do nothing.

Actual Results:
All folders looks equally valid. Tapping the unsupported app folder expands to show subfolders. The only way you know you can’t copy to here is by tapping the app folder than looking at the Copy button in the top right and seeing it is disabled.

Version:
11.2

Notes:
I only worked out that the file type being declared supported was the reason for this after a bit of experimentation and reading developer documentation.