Re: [StGIT] Not working on Windows with msysgit.

From: Karl Hasselström <kha@treskal.com>
Date: Aug 4, 2008, 09:25 UTC
Message-ID: <20080804092551.GC9425@diana.vm.bytemark.co.uk>
In-Reply-To: <g6kvmc$sqr$1@ger.gmane.org>

On 2008-07-28 19:29:49 +0200, Jurko Gospodneti? wrote:

> I believe StGIT fails to work on Windows with msysgit installed
> because of the way it runs its external executables. It assumes that
> the executable is available on the path and is named exactly 'git'.

Yes, that's correct.

Show 14 quoted lines

> This however is not the case on Windows with msysgit installed.
> There the 'git executable' is a batch script named git.cmd and stgit
> fails to find it causing all git calls to return an error code.
>
> Popen() calls in StGIT's run.py module seem to run their executables
> (git & gitk only as far as I saw from the sources) directly instead
> of running them through the shell in order to have the shell try all
> the default extensions (configured on Windows using the PATHEXT
> environment variable).
>
> One 'fix' that corrects this in all the use cases on Windows that I
> tried is to add the shell=True parameter to all Popen() calls in
> StGIT's run.py module (one in __run_io() and one in __run_noio()).
> This would however require more testing

Don't do that, please.

The reason to not go via the shell is that that way, we don't have to worry about quoting. That's a big pile of bugs that we never have to see again.

Plus, it's also slightly faster (especially on Windows, I guess) not to have to spawn a shell.

It'd be _much_ better to just be a little more flexible about which git command to use. Maybe look at PATHEXT if we're on Windows, or maybe let the user configure the location of git at stg install time. (RFC) patches welcome: :-)

> I do recall Python having some serious problems with these quoting
> in executed commands... something about external quotes getting
> stripped in some cases... I might be able to dig up a workaround
> from somewhere if needed...

That's the shell doing a level of unquoting. Nothing Python specific.

-- 
Karl Hasselström, kha@treskal.com
      www.treskal.com/kalle