ledger-config: parse gets a sourced spec. A fiscal year starts on the
first of a month (IRS Pub. 538); tax_classification is read by whole
words (Treas. Reg. 301.7701-3, Schedule C instructions; "business corp"
no longer reads as an S corp, "corporation or S corporation" is refused);
duplicate or blank members and shared capital accounts are refused; a
negative or non-grammatical receipt threshold is refused; codes trimmed.
tests/spec_config.rs (65 spec-blind tests, 14 properties), fuzz target
fuzz_config_parse (weekly). Mutation: 55 of 55 viable caught (from 25/38).
The receipt policy moves to ledger-config, with one loader
(effective_receipt_policy) and one decimal grammar, so the server and
the viewer enforce and show the same rule (the viewer had its own: only
expense-like debits, a silent $25 default, and no config.json).
ledger-mcp: a module spec (MCP 2025-06-18 tools, JSON-RPC 2.0, the
operating contract). Amounts in are exactly -?digits[.digits]; a number
that is one account's code and another's id (vendors, classes alike) is
refused, not guessed; the threshold is validated at startup. Fixed:
add_line with a bad class journaled the line before refusing;
profit_and_loss_by_class ignored `class`; aging buckets said "0". A wire
in front of rmcp answers malformed JSON with -32700 and invalid requests
with -32600 and their id (rmcp dropped the first, omitted the id).
tests/spec_mcp.rs (26 spec-blind tests: every tool's result against its
own outputSchema, a random-call state machine checking the journal is
untouched by every refusal, amount grammar, previews, the receipt policy).
ledger-gui: money, accounting, and dollars never round (they rounded to
cents, banker's style); export file names avoid Windows device names,
trailing dots and spaces, empty names, and 255-byte overflow; specs on
attention, history, fuzzy search, and axis ticks.
ledger-core: the lifetime profit_and_loss is renamed unclosed_earnings
(docs/testing.md #3).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
Max-testing pass, step 2: two spec decisions Stephen confirmed
(2026-10-13), each test-first.
Aging (arap::aging_bucket): a document due today was "1-30 days past
due"; it is Current, since past due starts the day after (QuickBooks'
convention). Spec in the doc comment. Boundary examples at every edge
(due today, 1, 30, 31, 60, 61, 90, 91 days) fail on the old code. A
property: the balance lands in exactly one bucket, and time only ages
it.
Member splits (periods::allocate): the last member absorbed every odd
cent, so the same partner always got or lost it. Now largest remainder:
each share rounded toward zero to the cent, leftover cents to the
largest remainders, ties to the earlier member, a loss the negation of
the gain. The core is a new kernel function, kernel::apportion,
allocation-free so Kani proves it (n <= 3): apportion_is_exact (it
succeeds exactly when the shortfall is under a unit per part; then the
parts sum to the whole, each gains 0 or 1 unit, one may take the
sub-unit fraction) and apportion_is_fair (never a unit to a part while
a larger remainder goes without). Kani found an off-by-one in the first
version: a shortfall of n units plus a fraction was accepted. Native
regression apportion_refuses_a_shortfall_of_a_unit_per_part_or_more.
Properties at Decimal (2,000 cases, up to 5 members): conservation,
within a cent of each exact share, fairness, sign symmetry; they fail on
the old rule. Bridge: apportion agrees on i64 and Decimal.
Contract: closes journaled before this change replay exactly. New
member closes journal "rounding": "largest_remainder"; journal lines
without it replay as CloseTo::MembersLastAbsorbs, the old rule
(periods::allocate_last_absorbs, pinned by
closes_journaled_under_the_old_rule_replay_with_it). The members'
equity statement isn't journaled and uses the new rule.
Open gap: Lean proof of apportion's sum law for any n (needs a
permutation lemma on the ranking); Kani covers n <= 3, properties n <= 5.
The Lean closing theorems already hold for any split summing to the
net.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GWVo7x3UHw5kwCUaWxiejX
The engine only had life-of-ledger P&L and balance sheet totals, so every
export labeled with a date range or as-of date (PDF, XLSX, CPA package)
printed all-time numbers under that label. Core now has:
- profit_and_loss_for_period(start, end, class?) and
balance_sheet_as_of(as_of), each with a line per account
(StatementLine: code, name, normal-side amount) and exact totals.
- Ledger::closing_entry_ids(). Period statements exclude closing entries.
A close (Dr revenue / Cr expense / net to Retained Earnings, dated at
period end) moves earnings; it doesn't earn or spend. Counting it made a
closed period's P&L read as break-even, and made the cash flow show zero
net income plus a fake "owner contribution" to Retained Earnings. The
as-of balance sheet keeps closing entries: after a close the earnings
belong in Retained Earnings, not current earnings.
Tests: tests/statements.rs, a two-month fixture with every expected number
computed by hand (Jan NI 1,700; Feb 880; balance sheets on four dates; a
closed January still reporting 1,700 and a cash flow with one financing
line). Mutation-checked: dropping the closing exclusion fails it (0 vs
1,700). Properties: period P&Ls partition a year at any split, and a
range's net income equals the change in current earnings across it, with
A = L + E on both dates.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MtYEaR6M6Ybdhm6X98BWNu