bug#20020: 25.0.50; `info-display-manual' should reuse existing window where buffer is displayed

[Eli Zaretskii <eliz@gnu.org>]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Wed, 09 Oct 2019 04:12:52 +0200
> Cc: 20020@debbugs.gnu.org
> 
> Drew Adams <drew.adams@oracle.com> writes:
> 
> > In my case, Info buffers (*info* and *info<N>*) are in dedicated
> > windows.  I expect `info-display-manual' to select such an existing
> > window.  That is, if the Calc manual is already displayed in an Info
> > buffer and I use `M-x info-display-manual' from some other buffer, I
> > expect the existing window showing that manual to be selected (and its
> > frame raised and focused, if necessary).
> >
> > Instead, `info-display-manual' displays the manual in the same window
> > where I invoke it, resulting in two windows (and frames in my case)
> > showing the same Info manual.
> 
> Makes sense.  I've now done this in Emacs 27, but while writing the
> code, it struck me that there has to be a ready-made function for this
> somewhere already.  I had a peek through the plethora of
> switch-to/pop-to functions, but I didn't find anything that did exactly
> this...
> 
> Does anybody know?

I don't really understand what you did and what was the original
problem, because info-display-manual already behaves for me like the
OP wanted.  It has behaved like that from day one, because I wrote it
to do so.  It only displays in *info* if there's not already an
*info*<N> buffer showing the requested manual (and in my Emacs
sessions, I never have *info* for long, I either kill it or rename to
*info*<N>.

Maybe the problem is that the OP did this in dedicated windows?
That's the only factor I could think of that is different from what I
do.