[MERGE] Add optional 'fetch_spec' to argument to Repository.fetch

[Jelmer Vernooij]

On Sun, 2009-03-08 at 17:54 +1100, Andrew Bennetts wrote:
> Jelmer Vernooij wrote:
> [...]
> > It would be nice if the fetch_spec parameter could be documented in
> > Fetch(). In particular, is it allowed to ignore this parameter ? Will
> > there be no revision id specified if this parameter is specified?
> 
> Yes, Robert pointed out the lack of documentation in his review too, so I
> extended the docstring as part of the tweaks to land the branch.  It now
> says:
> [...]
> I hope that answers your questions.  If it doesn't let me know and I'll try
> to improve the docstring some more.
Thanks, that helps. 

> Btw, in a couple of places (e.g.  InterPackRepo) that I didn't want to
> update for fetch_spec I put in some code like:
> 
>         if fetch_spec is not None:
>             if len(list(fetch_spec.heads)) != 1:
>                 raise AssertionError(
>                     "InterPackRepo.fetch doesn't support "
>                     "fetching multiple heads yet.")
>             revision_id = fetch_spec.heads[0]
>             fetch_spec = None
> 
> Which is just a simple backwards compatibility thing; currently the only
> fetch_spec used in bzr.dev is a PendingAncestryResult with a single head
> (and then only when sprouting or cloning into a newly created and
> non-stacked repo), so it's easy to treat that like a single revision_id as
> before.  Perhaps your plugins will want to do the same thing?
Thanks, I'll give that a try. Can I expect there to always be a "heads" variable in a fetch_spec ? 

Cheers,

Jelmer
-- 
Jelmer Vernooij <jelmer at samba.org> - http://samba.org/~jelmer/
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