Boris Feld <boris.feld@octobus.net> [Fri, 14 Dec 2018 17:25:41 +0100] rev 40976
sparse-revlog: protect C code against delta chain including nullrev
For unclear reasons, some repositories include nullrev (-1). Re-computing
delta for such repo remove nullrev from all chain, so some older versions have
been creating them.
This currently raise an IndexError with the new C code doing chain slicing as
it expect all item to be positive.
Both python and C code for reading delta chain preserve nullrev, and the Python
code for chain slicing handle the case fine. So we take the safe route and make
the new C code works fine in that case.