Re: [PATCH v3] git-svn: Make following parents atomic

> find_parent_branch generates branch@rev type branches when one has to
> look back through SVN history to properly get the history for a branch
> copied from somewhere not already being tracked by git-svn.  If in the
> process of fetching this history, git-svn is interrupted, then when one
> fetches again, it will use whatever was last fetched as the parent
> commit and fail to fetch any more history which it didn't get to before
> being terminated.  This is especially troubling in that different
> git-svn copies of the same SVN repository can end up with different
> commit sha1s, incorrectly showing the history as divergent and
> precluding easy collaboration using git push and fetch.
> 
> To fix this, when we initialise the Git::SVN object $gs to search for
> and perhaps fetch history, we check if there are any commits in SVN in
> the range between the current revision $gs is at, and the top revision
> for which we were asked to fill history.  If there are commits we're
> missing in that range, we continue the fetch from the current revision
> to the top, properly getting all history before using it as the parent
> for the branch we're trying to create.
> 
> Signed-off-by: Deskin Miller <deskinm@umich.edu>