Bulk Metadata "Set from ebook file(s)" when no cover image doesn't work
calibre version: 2.3[64bit]
This is the case when there's no cover image and it should render the first page of each book.
To recreate, start with book(s) without covers, or remove covers from a few test books using Modify ePub. Do bulk metadata edit, choose Change Cover, Set from &ebook file(s).
cover_from_format in single metadata does this fine, as does calling calibre.
But args.cover_action == 'fromfmt' in metadata_bulk.py doesn't.
I've traced it down into calibre.
I wanted to offer a patch, but I'm too unclear what the best solution would be.