bug#69983: Use category for display-buffer-alist

[Juri Linkov]

>> >>> One problem is that I can't find an alist item to limit
>> >>> the window height, i.e. can't find window-max-height
>> >>> that would be like window-min-height, but to set a max height.
>> >>> Could you suggest such an alist item?
>> >>
>> >> The intention was to have such behavior:
>> >> 1. after the first call that adds 1 line to the output buffer,
>> >>     resize the displayed buffer to 1 line height;
>> >> 2. after the second call grow the output window height to 2 lines,
>> >>     it seems fit-window-to-buffer should do this;
>> >> 3. after 10th call limit the window height to 10 lines only,
>> >>     so later calls should not increase the output window height
>> >>     more than 10 lines.
>> >
>> > You mean that when a 'window-height' action alist entry is provided that
>> > specifies 'fit-window-to-buffer' as 'window-height' value, we should
>> > pass it the value of any 'window-max-height' entry present as MAX-HEIGHT
>> > argument here
>> >
>> >          ((functionp height)
>> >      (ignore-errors (funcall height window))
>> >
>> > and probably do the same for all the other arguments of
>> > 'fit-window-to-buffer'?
>>
>> Probably we can't change the existing arguments to not break
>> backward-compatibility.  But this is fine since still can use
>> the explicit function call:
>>
>> diff --git a/lisp/emacs-lisp/warnings.el b/lisp/emacs-lisp/warnings.el
>> index 8b43c6a8726..75b519067ac 100644
>> --- a/lisp/emacs-lisp/warnings.el
>> +++ b/lisp/emacs-lisp/warnings.el
>> @@ -362,7 +362,12 @@ display-warning
>
> Why does adding a new feature require changes in existing features,
> let alone such basic features as warnings.el?  Can't we introduce the
> category and leave warnings.el, flymake.el, and others alone?  I don't
> want to make unsolicited changes in those other places, because that
> runs the risk of disturbing people's arrangements of windows and their
> habits as to where the various windows pop up.

This is part of continuing development to improve
window handling for users of horizontally split windows.