The sequence only knew accounts, lines, periods and closes, but that is no
longer where money moves: invoices, bills, their payments, write-offs and
voids are now first class, and the draft-state commands decide whether an
entry exists at all. Op gains each of them, on the same Ledger the store
wraps, with random parties, dates and amounts (including the raw-decimal
extremes).
The invariant after every sequence gains B-38: each control account equals
its documents as of three dates, and a control check too large to compute is
a refusal, never a difference. That is the identity that would catch a
payment tagged to the wrong document, or one that went unmatched, which the
trial balance alone cannot see.
Max-testing pass, ranks 4-6 and step 9 for ledger-core.
Fuzzing (rank 4): fuzz_op_sequence now drives balanced pairs, foreign
lines, periods, closes, and amounts from raw decimal bits, and asserts
the books stay valid (TB balances, posted entries validate, no draft in
a closed period); new fuzz_core_serde (every persisted core type
round-trips) and fuzz_store_open (a corrupt journal is an error, never a
panic); hangs count (-timeout=10). 54M executions; one crash:
- fuzz_journal_line: a number too big for an integer parsed as a float,
and its canonical form (which the hash chain covers) re-canonicalized
differently. The journal never holds floats (R-2), so the reader now
refuses them (JournalLine::parse, used by every journal reader);
regression a_journal_line_with_a_float_is_refused. Checked first: the
real books' journal has none. Rerun: 13.2M executions, clean.
Seeds in fuzz/seeds/ (synthetic, minimal); the grown corpora stay out of
git. `just fuzz <target> <seconds>`.
Miri (rank 4): the core's unit, bridge, and invariant tests under Miri
(our code has no unsafe; rust_decimal and chrono do): no undefined
behavior. `just miri`. A pinned nightly (nightly-2026-10-01, with miri)
is now in mise.toml.
Benchmarks (rank 6): criterion (new dev-dependency: the playbook's Rust
benchmark tool; none existed) in benches/books.rs; baselines in
docs/testing.md. The store's per-command rehearsal clone costs ~1 ms at
10k entries. No budget yet, so nothing gates on them. `just bench`.
CI: .github/workflows/check.yml runs `just check` on every push;
scheduled.yml runs proofs, the GnuCash oracle, fuzzing, and mutation
weekly. Tools come from mise.toml.
docs/testing.md: every layer, its oracle rank, command, runtime, and
gate; benchmark baselines; the ASSUMED invariants for the owner to reject;
the gap list with triggers. docs/oracle.md's fuzzing paragraph had
claimed persistent corpora that didn't exist; corrected.
Also: ledger-import now inherits the workspace lints (nightly cargo
warned).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX