It turned out the previous version had a subtle ordering bug when names
where the same length that went unnoticed for years. And at this point
is probably baked into the on-disk format permanently.
This redesign, with a named-ordered btree, relies quite a bit more on
name ordering, so it's unlikely the same mistake would make it through
without breaking something. And sure enough this bug was unintentionally
fixed at some point.
But still, better safe than sorry. Added tests over character ordering
and length ordering. Open to more ordering tests in the future.
Found by andriyndev
Christopher Haster
15cd1d29e0