Re: GIT_DIR unset in vc-git.el

[Emre Yolcu]

> `vc-region-history` says that the commit which introduced this GIT_DIR
> override is:
>
>      commit dc5e65b5deb2f5b67f6c3a06ae81c6b074bd4b56
>      Author: Dmitry Gutov <dgutov@yandex.ru>
>      Date:   Wed Jun 22 02:04:33 2016 +0300
>      
>          Unset GIT_DIR when calling Git commands
>          
>          * lisp/vc/vc-git.el (vc-git--call, vc-git-command):
>          Unset GIT_DIR (bug#23769).
>
> So you can check bug#23769 for further info.

Thanks for the pointer; the discussion on bug#23769 has been helpful in 
solving my issue.

> >    (defun git-link-home ()
> >      (interactive)
> >      (let ((process-environment
> >             `(,(format "GIT_DIR=%s" (expand-file-name "~/.home.git/"))
> >               ,(format "GIT_WORK_TREE=%s" (expand-file-name "~/"))
> >               ,@process-environment)))
> >        (recursive-edit)))
>
> Maybe you can save yourself the trouble.
>
>      cd ~/.home.git; git worktree add ~ main
>
> won't work because it will complain that ~ "already exists", but that's
> just Git being too protective.  You can "do it by hand":
>
>      cd ~/.home.git; git worktree add ~/dummy main
>      mv ~/dummy/.git ~/.
>      sed -i s/.dummy// ~/.home.git/worktrees/dummy/gitdir
>
> and then your home's Git data will still be stored in that bare
> `.home.git` but without having to mess with `GIT_DIR` and
> `GIT_WORK_TREE`.  The only/main difference is that you'll now have
> a `~/.git` file (which points at `~/.home.git/worktrees/dummy`).

If I understood the suggestion correctly, this would make every 
invocation of git under my home directory think that it is in a 
repository. This is not my goal, since I rarely work on maintaining my 
home directory but often on other Git repositories residing somewhere in 
home. With the "linking" approach above, I enter recursive edit, work on 
some configuration files, and exit when I am done so that git becomes 
unaware that home is kept under version control.