bug#19045: 25.0.50; [PATCH] vc-git-print-log use --follow

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Date: Fri, 16 Feb 2018 00:07:20 +0200
> Cc: 19045@debbugs.gnu.org
> 
> @@ -290,16 +290,12 @@ vc-do-command
>    (let* ((files
>         (mapcar (lambda (f) (file-relative-name (expand-file-name f)))
>                 (if (listp file-or-list) file-or-list (list file-or-list))))
> +      (message-truncate-lines t)

This should have a comment explaining why it is needed.  It should
also mention that messages in this function are formatted in a certain
way so as to put the important parts at the beginning, due to
potential truncation of long messages.

> -               (message "Running %s in background..." full-command))
> +               (message "Running  in background: %s" full-command))
                                   ^^
Extra blank.

> -                (message "Running %s in background... done" full-command))))
> +                 (let ((message-truncate-lines t))
> +                   (message "Finished in background: %s" full-command)))))

I find the original more in line with what we do elsewhere in Emacs.
If the problem is that "done" could be truncated, then please use

  Done in background: %s

> -           (error "Running %s...FAILED (%s)" full-command
> -                  (if (integerp status) (format "status %d" status) status)))
> +           (error "Failed (%s): %s"
> +                     (if (integerp status) (format "status %d" status) 
> status)
> +                  full-command))
>           (when vc-command-messages
> -           (message "Running %s...OK = %d" full-command status))))
> +           (message "Success (%d): %s" status full-command))))

"Failed" and "Success" don't go together well, as they use different
grammatical form.  How about using "Done" here as well?  And won't
status always be zero when it succeeds?  If not, I'd use

  Done (status=%d): %s

Thanks.