#1379 (board) mapped bit 8 -> .boardPost in SyncTypeFlags, making it a
known bit that spills the encoded bitfield into a second byte. But the
phantom-bit tests (added by #1373) predate that change and still assert
bit 8 is unknown, so main went red once both landed. Neither PR's CI
caught it — each was green against a main without the other.
The impl is correct (board is a real sync type); the tests were stale.
Update them to treat bits 9+ as phantom, expect the all-known field to
serialize to 2 bytes, and add a regression test that the board bit
survives decode while the phantom high bits are stripped.
Co-authored-by: jack <jackjackbits@users.noreply.github.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Follow-ups deferred from the REQUEST_SYNC review (#1371):
- SyncTypeFlags.init(rawValue:) now masks to the union of bits that map to a
known message type (derived from the bit↔type table, so it tracks new
types automatically). Phantom bits from a truncated/garbled flags field —
or a type a newer peer added — no longer live in the set as membership no
contains() matches yet toData() re-serializes.
- GossipSyncManager stored each latest announce as (hex-id string, packet)
and diffed announces against the stored string while every other type
recomputed the ID via PacketIdUtil. Collapsed the store to just the packet
and recompute the ID everywhere, removing the latent dual-path divergence.
- Documented the REQUEST_SYNC TLV table and marked fragmentIdFilter (0x06)
with a TODO(v2): it's parsed/re-serialized but never populated or honored
(reserved for incremental fragment sync) — finish or drop, not silent dead
surface.
Adds SyncTypeFlags phantom-bit/round-trip tests and a GossipSyncManager test
that an announce already in the requester's filter is suppressed (guards the
recompute path). Full suite: 1034 tests pass.
Co-authored-by: jack <jackjackbits@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
