Closes M3.1–M3.6. Parity safety net proving Go output matches Python
for every ported pure-domain function (M2.1–M2.9) and reconcile (M2.10).
Capture pipeline:
- scripts/capture_fixtures.py: calls each Python function with seeded
inputs, emits JSON fixtures to stdout (never writes files directly).
- scripts/scrub_fixtures.py: deterministic PII scrubber — SHA-256
pseudonyms for member names, digit-preserving hashes for VS/account/
bank_id, name-sweep in message text. Idempotent; no salt.
- scripts/_fixture_seeds.py: handcrafted seeds for all 11 functions;
synthetic names throughout (no real roster members).
- scripts/capture_all_fixtures.sh: convenience wrapper for full corpus
regeneration outside of make.
Fixture corpus (98 files, all PII-free):
- go/tests/fixtures/pure/<func>/<case>.json — 10 function directories.
- go/tests/fixtures/reconcile/<NN>_<case>.json — 10 branch-coverage
cases: greedy, overpayment credit, proportional remainder, even-split,
out-of-window, exception override, other: purpose, junior ?, multi-
person+month fan-out, unmatched.
Go parity tests (//go:build parity):
- go/tests/parity/parityio.go: generic LoadDir/RunAll helpers + typed
In/Out struct pairs for all 10 pure functions; Envelope decoder for
int/float/none disambiguation.
- 10 pure-function test packages + bespoke reconcile test with per-cell
float tolerance (math.Abs <= 0.01 for `paid` values).
Makefile: go-parity, go-test-all, capture-fixtures targets.
go/tests/fixtures/README.md: refresh workflow + PII audit guide.
Gate: make go-test green, make go-parity green (11/11 packages),
make go-lint clean (parity tag), make go-build clean.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
