Re: vc-modify-change-comment for "modern" backend fix

[Stefan Monnier]

> I think the modify-change-comment functionality hasn't seen much use,
> and still quite confused how it is intended to work.  E.g., in RCS, I
> have this as the latest commit (and in log view mode):
>
>   ----------------------------
>   revision 1.3
>   date: 2022/05/18 06:32:36;  author: ams;  state: Exp;  lines: +2 -1
>   Summary: this is a test message
>   ----------------------------
>
> At the beginning of the buffer, log-view-modify-change-comment, then
> you get a new buffer with the following:
>
>   revision 1.3
>   date: 2022/05/18 06:32:36;  author: ams;  state: Exp;  lines: +2 -1

That's a bug.  It should contain "Summary: this is a test message".

FWIW I implemented this functionality originally for CVS and I can't
remember ever testing it on another VCS, so I'm not surprised it doesn't
work right for other VCS.  I also remember having trouble using it last
time I needed it in CVS (which was quite some years ago), so it might
also be broken for CVS.  :-(


        Stefan