bug#50955: 28.0.50; info-look loads slowly due to python info lookup

[Eli Zaretskii <eliz@gnu.org>]

> From: Hugo Nobrega <hugonobrega@dcc.ufrj.br>
> Cc: 50955@debbugs.gnu.org
> Date: Sat, 02 Oct 2021 10:07:17 -0300
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> > OK, thanks.  Can you show the value of Info-directory-list, after
> > invoking info-look for the first time?  That should tell us in how
> > many directories does Emacs look for these missing Python manuals.
> 
> `Info-directory-list' is a list of length 208, almost entirely (like 99%)
> populated with paths from the package manager `straight'.

Ouch!  Now I understand why that search takes so long for you.

Not sure what to do about that.  Perhaps we should disable that
python*.info search if Info-directory-list is longer than some
threshold.

Or maybe we could remove the directories where packages are installed
from Info-directory-list, when doing that search?  With package.el, we
could record in some variable the list of directories we add to
Info-directory-list; maybe something similar is possible with
'straight' as well?

Lars, any other ideas?