Re: 23.0.60; Resizing may delete windows

[martin rudalics]

>> When
>> you de-maximize that frame the shrinking mechanism may remove the
>> control panel window provided `window-min-height' evals to the standard
>> value 4.
>
>
> "may remove" - are you suggesting this is not a bug?

The doc-string of `window-min-height' states

*Delete any window less than this tall (including its mode line).
The value is in line units.

Hence it's certainly not a bug.

> Or are you just
> saying you see that the code is written that way?

Not "or" but "and".  IIUC Jan tried to handle this in a way that small
windows are preserved.  Either he doesn't succeed always or the idea of
setting `window-min-height' to 1 gets in his way.

>> Setting `window-min-height' to 1 when the window wants a modeline is
>> asking for trouble and the documentation should say so.  However Emacs
>> should handle this case gracefully.
>
> Yes. But I am a little bit sorry for having mixed this trouble with the
> one I actually saw in ediff.

Your way of reproducing the problem was flawed.  It took me some time to
understand what you meant.  I suggest you set `window-min-height'
buffer-locally to 2 in the ediff control panel and look what happens
when the frame gets resized.  If the window still goes away we have a
bug.

> Anyway it is of course very good that you
> are taking care of the window-min-height=1 problem.

One aspect that puzzles me is why, when `window-min-height' equals 1,
Emacs doesn't simply display the window's modeline.  This way we could
simply shrink a window to its modeline and expand it whenever we need it
again.

Another problem is that Emacs doesn't record window sizes accross
(de-)maximizations.  Hence in your ediff control panel example you'd
have to fix the window-height at 1 in order to handle re-maximization as
intended :-(