Re: New multi-command facility displays in the wrong echo area.

[Gregory Heytings via "Emacs development discussions." <emacs-devel@gnu.org>]

>>> In any case, I think the condition could be relaxed: we only care 
>>> about how much space is left from the minibuffer text's end till the 
>>> end of the screen line, so "if minibuffer text size modulo 
>>> window-width is less than something" would be better, I think.  E.g., 
>>> if you use 70 instead of 67 in your recipe, the problem is mostly 
>>> gone.
>>
>> The condition could be refined indeed, but the modulo operation you 
>> propose would not work with variable pitch faces.
>
> It will, if the calculation is done in pixels.  The APIs you mentioned 
> can return pixels instead of columns, or there are alternatives which 
> do.
>

Indeed, this would also work:

(< (mod (car (window-text-pixel-size (active-minibuffer-window))) (window-text-width (active-minibuffer-window) t))
    (/ (car (window-text-pixel-size (active-minibuffer-window))) 2))

But going in that direction means that one should also take the current 
window height into account: if the miniwindow is tall enough, the above 
condition could be nil even though there would be enough room to display 
the message.

>> See above.  I've now read that bug thread, and I'm not at all convinced 
>> that the chosen solution was TRT, quite the contrary.
>
> We can discuss other solutions, of course.  However, significant changes 
> will have to wait for Emacs 28.
>

Ouch.  So this last-minute change will last for several years?

>> It seems to me that being wiser would mean taking the time to evaluate 
>> a proposed solution, instead of rejecting it outright based on a gut 
>> feeling.
>
> Please give me the credit of having done so.  I've given you no reason 
> to believe otherwise; disagreement doesn't imply incompetence or 
> sloppiness on my part.  It is simply unfair and even rude to suggest 
> that.
>

I do not suggest anything like that.  But I'm a doubting Thomas, and I 
can't give you this credit until I see a recipe that would convincingly 
demonstrate a potential problem that my proposed solution would create. 
Especially given I explained that this solution is only _at the moment_ 
the best solution, for earlier versions and the current version of Emacs, 
until a better solution is implemented.