Re: Stop frames stealing eachothers' minibuffers!

[Stefan Monnier]

Thanks Alan,

This looks pretty good to me (haven't tried it yet).
Some comments/questions below,


        Stefan


> @@ -86,6 +86,19 @@ useful on systems such as FreeBSD which ships only with 
> "etc/termcap".
>  * Changes in Emacs 28.1
>  
>  +++
> +** Switching frames when a minibuffer is active has been rationalized.
> +By default, the minibuffer is moved to the newly selected frame.  When
> +the current command is continued (by completing the minibuffer
> +action), it takes effect in the frame the minibuffer was first opened
> +in.  An alternative behavior is available by customizing
> +'minibuffer-follows-frame' to nil; here, the minibuffer stays on the
> +frame it was first opened on, and you must switch back to this frame
> +to continue or abort the current command.  The old (pre 28.1),
> +somewhat chaotic behavior is no longer available.
> +
> ++++
> +*** A new system for displaying documentation for groups of function is 
> added.
> +
>  ** New system for displaying documentation for groups of function.
>  This can either be used by saying 'M-x shortdoc-display-group' and
>  choosing a group, or clicking a button in the *Help* buffers when

Looks like a chunk of Lars's shortdoc got brought along.

> +static bool
> +minibuf_follows_frame (void)
> +{
> +  return !NILP (Fdefault_toplevel_value (Qminibuffer_follows_frame));
> +}

I can't think of any reason why we'd need to bother with
`Fdefault_toplevel_value` here.  I think the only justification would be
if using some other value could result in a crash or in garbled display,
but AFAICT it could only result (in the worst case) in a vaguely
unexpected behavior where the mininbuffer follows the frame when it
shouldn't or vice versa.

> +          FOR_EACH_FRAME (tail, frame)
> +            {
> +              if (EQ (XWINDOW (XFRAME (frame)->minibuffer_window)->contents,
> +                      buffer))
> +                {
> +                  minibuf_window = XFRAME (frame)->minibuffer_window;
> +                  goto after_set;
> +                }
> +              minibuf_window = sf->minibuffer_window;
> +            after_set: ;
> +            }

I don't understand the:

    minibuf_window = sf->minibuffer_window

Won't this undo the

    minibuf_window = XFRAME (frame)->minibuffer_window;

executed in a previous iteration?
Should this be moved to just before the loop maybe?

> +      /* OLD STOUGH, 2020-10-21 */

Not sure how useful this is.  I'd either remove this comment or replace
it with an actual explanation of what's going on and/or how the code
used to work.


        Stefan