bug#36270: executable-find does not find shell commands on MSYS2

[Juanma Barranquero <lekktu@gmail.com>]

On Wed, Jun 19, 2019 at 6:24 PM Eli Zaretskii <eliz@gnu.org> wrote:

> Kids down here have a saying: "almost doesn't count" ;-)

Err... Don't want to think about the context for *that* ;-)

> Exactly.  So what would be the point of having a general-purpose API
> return files that can be useful only with some methods of running a
> program?  It will only cause confusion and bug reports.

That's an argument about the general-purpose API return these files,
not about having a special-purpose API, isn't it?

> So to support that, we will need to change sys_spawnve and/or
> cmdproxy to detect an extension that appears in PATHEXT, and then
> either invoke through cmdproxy or use ShellExecute instead of
> CreateProcess.  And this is the more complex part of the job.

Ok, now I understand. I will look into it, but no promises and of
course no hurry.

> One non-ugly fix is to use RCS from the ezwinports site.  The binaries
> there are 32-bit, but I don't think it will make any difference.

With your binaries installed the test will pass (haven't tested yet,
but seems likely). But that does not solve the issue that someone with
a MSYS2 build environment has a working rcs installation, and yet the
vc-tests fail. Of course, the thing is that, from Emacs POV, that's
not a "working rcs installation" at all...