Subject: vc-next-action overwrites changes in non-checked-out RCS file

From: Jonathan Kamens <[email-masked]>
Date: Wed, 16 May 2012 15:29:07 -0400

GNU Emacs 24.0.95.1 (x86_64-redhat-linux-gnu, GTK+ Version 2.24.10) of 
2012-04-06 on x86-13.phx2.fedoraproject.org

Make an RCS file writable with chmod +w without locking it.

Make changes to the file.

Type C-x v v.

The file will be locked and checked out and your changes will be 
overwritten.

This is Bad, Bad, Bad. It needs to check if there are non-checked-out 
changes and ask whether to preserve them.

It used to do this. I have no idea why it's behaving differently now or 
when it started behaving this way, but it's clearly wrong and dangerous, 
given the potential to lose work.

I lost a whole day of work recently as a result of this bug. Yeah, it 
was user error, but that's not really the point. It's easy to protect 
the user from losing work due to this editor, and it's something that 
Emacs used to do, so it should continue to do it.

   jik