Subject: Re: bug#33490: 27.0.50; auto-save-visited-mode clears the echo area every time the save interval is hit

From: Terje Larsen <[email-masked]>
Date: Sat, 24 Nov 2018 21:26:06 +0100

Thank you for the quick fix, that seems to solve the issue.
Applying this patch and repeating the same kind of testing procedure produced the expected result.

> On 24 Nov 2018, at 19:40, Eli Zaretskii <[email-masked]> wrote:
> 
>> From: Terje Larsen <[email-masked]>
>> Date: Sat, 24 Nov 2018 12:56:19 +0100
>> 
>> M-x auto-save-visited-mode
>> M-: (message "%s" "hello")
>> 
>> ... Wait 5 seconds ...
>> 
>> Now the message buffer gets cleared and you lose the message. This is
>> causing usability issues when using eldoc/reading some output message as
>> it continously gets cleared.
>> 
>> I would expect the `auto-save-visited' feature to not change the behaviour
>> of the Echo Area. If you compare this to the `auto-save-mode' which
>> outputs a message indicating a save, but restores the Echo Area after.
>> 
>> I have tracked down this to the `save-some-buffers' function or more
>> specifically the `map-y-or-n-p' function that it calls. In this function
>> there is a call to message like `(message "")`.
> 
> Right.  Does the patch below fix the problem?
> 
> diff --git a/lisp/emacs-lisp/map-ynp.el b/lisp/emacs-lisp/map-ynp.el
> index 8260af5..93235bd 100644
> --- a/lisp/emacs-lisp/map-ynp.el
> +++ b/lisp/emacs-lisp/map-ynp.el
> @@ -79,6 +79,7 @@ map-y-or-n-p
> 
> Returns the number of actions taken."
>   (let* ((actions 0)
> +         (msg (current-message))
> 	 user-keys mouse-event map prompt char elt def
> 	 ;; Non-nil means we should use mouse menus to ask.
> 	 use-menus
> @@ -250,9 +251,10 @@ map-y-or-n-p
>       (if delayed-switch-frame
> 	  (setq unread-command-events
> 		(cons delayed-switch-frame unread-command-events))))
> -    ;; Clear the last prompt from the minibuffer.
> +    ;; Clear the last prompt from the minibuffer, and restore the
> +    ;; previous echo-area message, if any.
>     (let ((message-log-max nil))
> -      (message ""))
> +      (message (or msg "")))
>     ;; Return the number of actions that were taken.
>     actions))