Comment 1 for bug 154283

I'm not following this closely but I thought I'd mention a bit of diagnosis. I think the lines in question are:
                method = self._index.get_method(cursor)
                if method == 'fulltext':
                    next = None
                else:
                    next = self.get_parents(cursor)[0]

Which would indicate that we have a record with no parents that is not marked as a fulltext. This shouldn't be possible because we don't have anything to delta against if we don't have any parents. (So it should *have* to be a fulltext).

It may be that Packs change that logic, though I'm not sure how. We certainly could do:

parents = self.get_parents(cursor)
if not parents:
  next = parents[0]

However, that would miss the case where we have the fulltext cached *and* parents. And it seems like a data corruption to have no parents but no fulltext.

Could it just be that http://people.ubuntu.com/~robertc/baz2.0/repository is broken?