Re: make pred customable in auto-save-visited-mode

[Eli Zaretskii <eliz@gnu.org>]

> From: 纪秀峰 <jixiuf@qq.com>
> Date: Sat, 31 Mar 2018 00:59:19 +0800
> Feedback-ID: esmtp:qq.com:bgforeign:bgforeign1
> 
> When I enable  auto-save-visited-mode and start an ediff merge session 
> It always prompt me save "*ediff-merge*” to a file.

Why is that a problem?  *ediff-merge* is a buffer where you prepare
the merge, and that merge will eventually be saved to some file,
right?  So it doesn't sound wrong to offer to save it.

>   (setq auto-save--timer
>         (when auto-save-visited-mode
>           (run-with-idle-timer
>            auto-save-visited-interval :repeat
>            #'save-some-buffers :no-prompt
>            (lambda ()  ;;<————————————how about make this customable
>              (not (and buffer-auto-save-file-name
>                        auto-save-visited-file-name)))))))

Letting users customize a non-trivial function is not the best way of
affecting this behavior.  I think you can have what you want by adding
a function to ediff-startup-hook, and in that function set
buffer-auto-save-file-name of the *ediff-merge* buffer to nil.