Each row's exact residual reproduced against rsync 3.4.1:
- basis dirs (--compare/copy/link-dest): FastSync xxHash-verifies a basis hit
while rsync --size-only installs the wrong same-size basis content.
- --delay-updates: the fixed .fastsync-stage name wipes an unrelated
destination entry of that name even without --delete; rsync leaves it.
- --fuzzy: deterministic name/size heuristic (10x window), not rsync's matcher.
- --dry-run: would-delete report over-reports the updated file and an
excluded-but-protected extra, and ordering differs.
Docs: RSYNC_COMPAT tally 109/16/31; HANDOFF item 9. clang-format + cppcheck +
ASan + full suite clean.
Accept the full rsync 3.4.1 --info (backup, del, flist, mount, nonreg,
progress, remove, symsafe) and --debug (acl, backup, bind, chdir, connect,
cmd, del, deltasum, dup, exit, filter, flist, fuzzy, genr, hash, hlink,
iconv, nstr, own, recv, send, time) vocabularies, plus the historical
syms/hl/owner aliases, with level suffixes. Categories FastSync already
emits (copy/name/misc/skip/stats and io/proto/pack/util) still set their
log flags; the rest are accepted but silent. Unknown names remain
rejected by name, matching rsync. Update the CLI unit tests and the
rsync-parity integration tests (previously they required del/filter to be
rejected).
- Assert FastSync's sparse/preallocate block accounting matches rsync 3.4.1
for a hole file (preallocate wins over sparse, exactly like rsync).
- Assert --ignore-existing is answered by the receiver before the sender
transmits the payload (CountingProxy wire volume near-zero).
- CountingProxy.run gains a bounded join_timeout so tests that only need the
client->server count do not wait for the server's idle socket.
- Fix the stale protocol 2.24.0 comment in test_config.c (golden is 2.26.0).