Tim Burke e53c82cd32 sharder: Prevent ValueError when no cleaving contexts
Otherwise, we trip an error in logs:

   ValueError: max() arg is an empty sequence

Co-Authored-By: Matthew Oliver <matt@oliver.net.au>
Change-Id: I68f52f28edf9bdb9c534983cf353b72ecfaac426
2021-04-07 12:25:04 +01:00
..
2020-05-15 22:38:04 -07:00