- review finding: field_idx=0 and back_off=0 (fresh WAL, offset 0) meant
a u32/u64 swap of these two values wrote identical zero bytes either
way — undetectable by the prior assertions
- test_delta_record: new dedicated 3-scalar-field class (not shared
KEYS_CLASSES) so field_idx can be a nonzero, fixed-8-byte value without
a Text field's variable-length encoding complicating the fixed body
size assertion
- stage+commit a filler row first so the target row's insert record (the
delta's back-pointer) lands at a nonzero offset, not the WAL's initial 0
- delta now targets field_idx=2 with back_off=base_off, both nonzero and
distinct from each other and from class_id=0
- class_id stays 0: this fixture registers exactly one class, so there is
no other value to give it without an unused second class purely to
shift an index
- verified live: temporarily swapped the field_idx/back_off wput calls in
wal.c, confirmed test_wal now fails (fidx==49 want 2, back==2 want 49),
then reverted — wal.c diff is a no-op, only the test changed
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
(cherry picked from commit 20ba0965e15e200641b8b63893a2f238a0279fba)
shoney.arickathil
b860823dad