Land the three test-pattern shapes the Explore-agent investigation
of fox's overnight π* kernel commits surfaced. Patterns 1-8 in
this doc were the original 9-item checklist; patterns 9-11 are
new domain-specific contract pins that the π* kernels require but
that t3_bound_calculator (the original exemplar) does not.
== New patterns added ==
**§9 Projective-contract pin (one-way canonicalizers)**
For canonicalizers whose output type ≠ input type — output is
not in the input domain by design — assert that re-applying the
function raises. Pinned in code-py-ast@v1 (Python → S-expr) and
time-series-quantized@v1 (JSON → quantized text). When the output
type DOES equal the input type (arithmetic kernel's ℚ → ℚ),
use the dual: round-trip idempotence
``canonicalize(canonicalize(x)) == canonicalize(x)``. Both pin a
contract; pick by the kernel's type signature.
**§10 Dispatch-order pin (Python type-hierarchy gotchas)**
Python's ``bool`` subclasses ``int``, so a naive ``isinstance(x,
int)`` chain never reaches a bool branch. Kernels distinguishing
``True`` from ``1`` (Python AST normalizers, etc) must check
``bool`` first. Pin the branch order so a "simplify the dispatch"
PR fires loud. From ``593550b``.
**§11 Tie-breaking-rule pin (banker's rounding)**
Python's ``round()`` uses ties-to-even (PEP 3141): 0.5→0, 1.5→2,
2.5→2. Naive switch to ``math.floor(x + 0.5)`` (round-half-up)
produces 0.5→1, 1.5→2, 2.5→3 — different output for tie inputs
without breaking non-tie tests. From ``2585d3c``.
Each pattern has worked-example pseudocode + cross-reference to
the actual test file in fox's commit. The pattern numbers extend
the existing 1-8 sequence; renumbering would have invalidated
prior references.
== Checklist updates ==
Items 10/11/12 added (conditional — only when the kernel's shape
exposes the corresponding surface). Many calculator modules
(t3 bound, anchor PRG) need only items 1-9.
== Exemplar files reorganized ==
Replaced the single-exemplar reference (t3_bound_calculator only)
with a 5-file table cross-referencing the 9-12 checklist items
each exemplar covers:
test_t3_bound_calculator.py items 1-9 (53 tests)
test_pi_star_arithmetic.py items 1-6 + 9 + idempotence (56)
test_pi_star_logic.py items 1-6 + 9 + 11 (53)
test_pi_star_code.py items 1-6 + 9 + 10 + 11 (32)
test_pi_star_time_series.py items 1-6 + 9 + 10 + 12 (35)
All five test counts AUTOCOUNT-tagged so future drift fires the
regression test landed in ``fc5ba50`` / ``03c0f6a``. Total tagged
claims now 49 (was 44; +5).
== Source ==
Patterns surfaced from the Explore-agent investigation of fox's
overnight 2026-05-10 commits (``6c9bc04`` arithmetic, ``e7bef5f``
logic, ``593550b`` code, ``2585d3c`` time-series — 176 KATs total
across 4 π* canonical-projection kernels). The agent walked each
commit, noted the test patterns that didn't appear in the
original 9-item checklist, and reported the pattern shapes back.
This commit promotes those findings from session memory to
architecture-reference docs.
Verification:
$ pytest tests/test_doc_counts.py -v
3 passed in 3.39s
russell@unturf.com
f5dbfabed5