bug#28843: 26.0.90; gnus kills unsaved message buffer

[Nick Helm <nick@tenpoint.co.nz>]

On Thu, 26 Oct 2017 at 13:52:13 +1300, Nick Helm wrote:

> On Sun, 15 Oct 2017 at 20:46:25 +1300, Nick Helm wrote:
>
>> Gnus exits, and the unsaved message buffer dies with it, without prompts
>> to save.
>
> It seems the behaviour is intentional ... This commit changed
> `gnus-clear-system' to include this:
>
>   #+begin_src emacs-lisp
>   ;; Kill Gnus buffers.
>   (do-auto-save t)
>   (dolist (buffer (gnus-buffers))
>     (when (gnus-buffer-exists-p buffer)
>       (with-current-buffer buffer
>   	   (set-buffer-modified-p nil)
>   	   (when (local-variable-p 'kill-buffer-hook)
>   	     (setq kill-buffer-hook nil))))
>     (gnus-kill-buffer buffer))
>   #+end_src
>
> So gnus is at least auto-saving draft messages before zapping them.
>
> Is there a better way to do this though? I think the user should at
> least have some warning that an unsaved buffer is about to be
> automatically killed.

One solution (though not a very good one IMHO) would be to make the
auto-save depend on the user's value of guns-interactive-exit. For
example:

--- a/lisp/gnus/gnus-start.el	2017-10-26 12:49:43.000000000 +1300
+++ b/lisp/gnus/gnus-start.el	2017-10-26 12:45:12.000000000 +1300
@@ -731,11 +731,12 @@
     (kill-buffer (get-file-buffer (gnus-newsgroup-kill-file nil))))
   (gnus-kill-buffer nntp-server-buffer)
   ;; Kill Gnus buffers.
-  (do-auto-save t)
   (dolist (buffer (gnus-buffers))
     (when (gnus-buffer-exists-p buffer)
       (with-current-buffer buffer
-	(set-buffer-modified-p nil)
+        (unless gnus-interactive-exit
+          (do-auto-save t t)
+	(set-buffer-modified-p nil))
 	(when (local-variable-p 'kill-buffer-hook)
 	  (setq kill-buffer-hook nil))))
     (gnus-kill-buffer buffer))