bug#50733: 28.0.1; project-find-regexp can block Emacs for a long time

[Eli Zaretskii]

> Cc: 50733@debbugs.gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Fri, 24 Sep 2021 01:40:58 +0300
> 
> Perhaps on a platform like macOS we should consider bundling some 
> up-to-date search program, be it GNU Grep or Ripgrep.
> 
> Eli, have there ever been a similar proposal under discussion? IIRC 
> having to install external tools has been an issue on MS Windows as well 
> for a long time. We give recommendations, but Grep has never been 
> distributed together with Emacs. Any particular reason?
> 
> For comparison, VS Code bundles ripgrep. Or at least its macOS releases do.

Bundling an external program is problematic, but it can be done, of
course, provided that the license is right.  The problem is, we don't
provide macOS binaries, and we cannot rely on the fact that the
Windows binaries distribution will have its maintainer forever: we
already had periods of time without such a person.

We can recommend installing such tools, of course.

Btw, I don't understand why we focus on general-purpose text-searching
tools for these features.  Why not focus on packages like ID Utils
instead, they are so much faster.  Daniel, could you time the same
search in that large tree when xref-search-program is 'gid'?  (You'd
need to run 'mkid' first, to create the ID database, but that is
one-time, and is very fast.)  As I told many times, I think this is
the future: program language sensitive tools that use a precomputed
DB.