bug#38343: 27.0.50; vc git: Cannot edit outgoing log (like git commit --amend)

[Dmitry Gutov]

On 23.11.2019 12:01, Fredrik Nyqvist wrote:

> I would like to use vc mode to edit an outgoing commit message.
>
> Steps to reproduce:
> 1. emacs -Q /path/to/git/repo
> 2. Edit a file and then
> 3. Run vc-next-action to create a commit: C-x v v
> 4. Write a commit message and end with C-c C-c
> 5. Now Open the outgoing log (vc-log-outgoing) : C-x v O
> 6. Try to edit the commit message (log-view-modify-change-comment): e
>
> This message is printed:
>
> log-view-current-file: Unable to determine the current file

Yes. This feature seems unfinished, and it was never updated for the 
newer VC systems.

However, we have an option for amending the last commit (press C-x C-e 
in an already open log-edit buffer). It only works with Git and Hg now.

It would be good to unify these two features somehow.