0.3.7 (unpublished), owner-chosen option A. A tombstone is now pruned only when
it is past TombstoneRetention AND the peer is known to hold it:
- held while database-wide or per-table snapshot debt is outstanding (the
snapshot is built from the row-version ledger, so a pruned tombstone is a
delete it can no longer carry — the issue's second path);
- a local tombstone held while its delete is still in the unacked oplog.
Delivery (delta ack covering the delete, or snapshot debt discharged) restamps
tombstone_utc so retention runs from delivery. New optional
LocalDb:Replication:TombstoneHardCap (default off, >= TombstoneRetention)
bounds an undelivered tombstone's life. No proto, lib_schema_version or
on-disk schema change.
Regression test TombstoneResurrectionTests (two real nodes over loopback gRPC):
offline update on B, newer delete on A, A's clock +8 days (oplog age cap +
tombstone prune) -> reconnect. Fails on 0.3.6 (row resurrected), passes now;
plus a no-prune positive control and a pruned-after-delivery control, and five
controlled-clock OplogStore tests. Each guard clause mutation-killed. 259/259.
Claude-Session: https://claude.ai/code/session_01GT67AEHd2Acv1YPwGfXEoV