[git-buildpackage] Would it be possible for pristine-tar to not be an absolute path?

[Nish Aravamudan]

On 30.08.2017 [19:02:20 +0200], Guido Günther wrote:
> Hi,
> On Wed, Aug 30, 2017 at 09:37:28AM -0700, Nish Aravamudan wrote:
> > Hello,
> > 
> > I am currently using gbp in a snap for `git-ubuntu`, a tool similar to
> > dgit for doing Ubuntu source package work. The snap contains all its
> 
> Can you point me to the snap?

Yep; I interpreted your statement in three different ways :)

1) To install the snap:

  sudo snap install git-ubuntu --classic

2) Source: 

https://code.launchpad.net/~usd-import-team/usd-importer/+git/usd-importer/+ref/master

The snap is automatically built from master currently.

3) The error we get (without pristine-tar installed in the host, which
is what I'm trying to avoid requiring by putting it in the snap) is:

gbp:debug: /usr/bin/pristine-tar [] ['commit', '/tmp/tmpk6ru7ya5/.git/git-ubuntu-cache/virt-manager_0.5.4.orig.tar.gz', 'c0a614c62bad2d63e671ff3c1ae853380e952cab']
gbp:error: Import of /tmp/tmpk6ru7ya5/.git/git-ubuntu-cache/virt-manager_0.5.4.orig.tar.gz failed: Couldn't commit to 'pristine-tar' with upstream 'c0a614c62bad2d63e671ff3c1ae853380e952cab': execution failed: [Errno 2] No such file or directory

...

The host doesn't have pristine-tar, but it is available at:

/snap/git-ubuntu/current/usr/bin/pristine-tar.

The former ends up in snaps as $SNAP and we have a wrapper around our
commands that ensures $SNAP/usr/bin (and a bunch of other common paths)
are in $PATH.

To be clear, we only use gbp for orig tarball handling currently (we
import-orig the tarballs published for Debian & Ubuntu, and use
buildpackage (eventually export-orig, once it's available) to get the
tarballs back out).
 
> > dependencies, including pristine-tar at paths within the snap (which I
> > ensure are in PATH when my tool runs), but gbp has a hard-coded path
> > to pristine-tar:
> > 
> > gbp/pkg/pristinetar.py:
> > ...
> > class PristineTar(Command):
> >     """The pristine-tar branch in a git repository"""
> >     cmd = '/usr/bin/pristine-tar'
> > 
> > Is that strictly necessary for the way Command works? Would it be
> > possible to allow the cli (since it may not be override-able
> > otherwise) to specify where pristine-tar lives rather than it being
> > hardcoded?
> 
> Is pristine-tar in your $PATH? As with subprocess when not going through
> a shell we need an absolute path. I'm happy to add logic to check in
> $PATH or different locations but I rather understand the problem first.
> (I'd be great if we wouldn't need even more cli options).

Yeah, pristine-tar is in $PATH (within the context of the snap wrapper
scripts, which are the only entry points to our programs anyways).

I see what you're saying, since we aren't using a shell, we don't have a
PATH to resolve?

Agreed on not needing more cli options, if at all possible to avoid :)

Thanks,
Nish
-- 
Nishanth Aravamudan
Ubuntu Server
Canonical Ltd