Re: Cannot push anything via export transport helper after push fails.

From: Felipe Contreras <felipe.contreras@gmail.com>
Date: May 11, 2013, 13:57 UTC
Message-ID: <CAMP44s1YhQR0o-0CLc2PG-EJTZdN4tha-4BVEUy-K_Av81D=GQ@mail.gmail.com>
In-Reply-To: <20130511162936.0354e5d7@opensuse.site>

On Sat, May 11, 2013 at 7:29 AM, Andrey Borzenkov <arvidjaar@gmail.com> wrote:

Show 25 quoted lines

> I noticed that using git-remote-bzr, but as far as I can tell this is
> generic for all transport helpers using fast-export.
>
>
>
> What happened was "git push" failed due to merge conflict. So far so
> good - but from now on git assumes everything is up to date.
>
> bor@opensuse:/tmp/test/git> git push origin master
> To bzr::bzr+ssh://bor@localhost/tmp/test/bzr
>  ! [rejected]        master -> master (non-fast-forward)
> error: failed to push some refs to 'bzr::bzr+ssh://bor@localhost/tmp/test/bzr'
> hint: Updates were rejected because the tip of your current branch is behind
> hint: its remote counterpart. Merge the remote changes (e.g. 'git pull')
> hint: before pushing again.
> hint: See the 'Note about fast-forwards' in 'git push --help' for details.
> bor@opensuse:/tmp/test/git> git push origin master
> Everything up-to-date
> bor@opensuse:/tmp/test/git>
>
> The problem seems to be that git fast-export updates marks
> unconditionally, whether export actually applied or not. So next time
> it assumes everything is already exported and does nothing.
>
> Is it expected behavior?

Indeed, this is the way it currently works, and it's not easy to fix. We would need some way to make fast-export wait until we know the exit status of the remote helper, and then tell it when it failed, so the marks are not updated.

However, the way remote-bzr/hg work is that the commits are still there anyway. So if you merge the next time you push those commits are already converted, so it's not a problem if fast-export is not exporting them again.

So even though it's not ideal, it should work.

The problem is when the remote-helper crashes and the marks of fast-export and the remote-helper are out of sync, and then the user is really screwed.

Cheers.

-- 
Felipe Contreras