Re: [PATCH] Fix vc-working-revision return nil when default-directory is not inside repo

[Dmitry Gutov]

On 17.05.2020 17:17, Ilya Ostapyshyn wrote:
> Despite the complex scenario I described, the issue is not hard to
> reproduce.
>
> 1. Open a file in a Git repository
> 2. (vc-working-revision buffer-file-name)
>     => working revision hash
> 3. (cd "/")
> 4. (vc-file-clearprops buffer-file-name) ;; clear the cached revision in 
> symbol's props
> 5. (vc-working-revision buffer-file-name)
>     => nil

OK, thank you for the examples. Indeed, the behavior is not 
well-defined, so let's fix it, especially considering the performance 
difference is negligible.

I've pushed a fix to master, a slightly different version of your patch. 
This will be in Emacs 28.

Regarding doing it in another place, that would be inside 
vc-git-working-revision. Maybe we'll switch to that approach later, 
given that neither Hg not Bzr seem to have exhibited the same problem.

But I went with the "safer" option now.