On 6 August 2018 at 17:26, Jeff King <peff@peff.net> wrote:

> I suspect it still has a bug, which is that it is handling this
> first-parent-goes-left case, but probably gets the straight-parent case
> wrong. But at least in this form, I think it is obvious to see where
> that bug is (the "three" in the comment is not accurate in that latter
> case, and it should be two).

Yes, thanks, it makes a lot more sense this way. I believe the
attached handles both parent types correctly.