jelmer/dulwich — pull request #66 by bpollack (2012-07-11 14:40:37+00:00)
Title: Do not crash when trying to walk an empty set

If you're trying to walk an empty set (e.g., the `exclude` list effectively included the entire history), then the walker crashes, because `self._last` won't ever have been set. This patch simply ensures that `self._last` has been set to some value before trying to compare against it. I believe that the resulting behavior (leaving `reset_extra_commits = False`) is the right one for that case.