commerce: catalog facts + multidirectional relations + conformance harness (16 tests)

catalog.sx — catalog snapshot (products/variants/stock as fact tuples),
relational accessors (producto/varianto/stocko, derived priceo/classo/
unit-priceo) usable forward and backward, deterministic catalog-price/
-class/-has? helpers. Money is integer minor units. conformance.sh runs
suites on the miniKanren stack and emits scoreboard.{json,md}.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/commerce/catalog.sx

@@ -0,0 +1,83 @@
+;; lib/commerce/catalog.sx — catalog snapshot + relational accessors.
+;;
+;; A catalog snapshot is an immutable dict:
+;;   {:products (list (list sku price class) ...)
+;;    :variants (list (list sku variant delta) ...)
+;;    :stock    (list (list sku variant qty) ...)}
+;;
+;; Money is integer minor units (pence/cents). class is a keyword product
+;; class consumed later by tax and promotion relations. delta is a signed
+;; price adjustment for a variant; qty is on-hand stock for (sku,variant).
+;;
+;; Accessor relations take the snapshot as the first argument and are fully
+;; multidirectional: (producto cat "widget" p c) binds p,c forward;
+;; (producto cat s 1000 c) enumerates every sku priced 1000 backward.
+
+(define empty-catalog {:products (list) :stock (list) :variants (list)})
+
+(define make-catalog (fn (products variants stock) {:products products :stock stock :variants variants}))
+
+(define cat-products (fn (cat) (get cat :products)))
+(define cat-variants (fn (cat) (get cat :variants)))
+(define cat-stock (fn (cat) (get cat :stock)))
+
+;; --- core fact relations ---
+
+(define
+  producto
+  (fn
+    (cat sku price class)
+    (membero (list sku price class) (get cat :products))))
+
+(define
+  varianto
+  (fn
+    (cat sku variant delta)
+    (membero (list sku variant delta) (get cat :variants))))
+
+(define
+  stocko
+  (fn
+    (cat sku variant qty)
+    (membero (list sku variant qty) (get cat :stock))))
+
+;; --- derived relations ---
+
+(define
+  priceo
+  (fn (cat sku price) (fresh (c) (producto cat sku price c))))
+
+(define
+  classo
+  (fn (cat sku class) (fresh (p) (producto cat sku p class))))
+
+;; Effective unit price of a (sku,variant): base + variant delta.
+(define
+  unit-priceo
+  (fn
+    (cat sku variant price)
+    (fresh
+      (base delta)
+      (priceo cat sku base)
+      (varianto cat sku variant delta)
+      (pluso-i base delta price))))
+
+;; --- deterministic lookups (first solution under fixed fact order) ---
+
+(define
+  catalog-price
+  (fn
+    (cat sku)
+    (let
+      ((rs (run 1 p (priceo cat sku p))))
+      (if (empty? rs) nil (first rs)))))
+
+(define
+  catalog-class
+  (fn
+    (cat sku)
+    (let
+      ((rs (run 1 c (classo cat sku c))))
+      (if (empty? rs) nil (first rs)))))
+
+(define catalog-has? (fn (cat sku) (not (nil? (catalog-price cat sku)))))

lib/commerce/conformance.sh

@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+# lib/commerce/conformance.sh — run commerce test suites in one sx_server
+# process per suite, emit scoreboard.json + scoreboard.md.
+#
+# commerce-on-sx builds pricing/promotion as miniKanren relations, so every
+# suite loads the miniKanren stack first, then the commerce modules.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+SUITES=(catalog)
+
+OUT_JSON="lib/commerce/scoreboard.json"
+OUT_MD="lib/commerce/scoreboard.md"
+
+run_suite() {
+  local suite=$1
+  local file="lib/commerce/tests/${suite}.sx"
+  local TMP
+  TMP=$(mktemp)
+  cat > "$TMP" << EPOCHS
+(epoch 1)
+(load "spec/stdlib.sx")
+(load "lib/r7rs.sx")
+(load "lib/guest/match.sx")
+(load "lib/minikanren/unify.sx")
+(load "lib/minikanren/stream.sx")
+(load "lib/minikanren/goals.sx")
+(load "lib/minikanren/fresh.sx")
+(load "lib/minikanren/conde.sx")
+(load "lib/minikanren/run.sx")
+(load "lib/minikanren/relations.sx")
+(load "lib/minikanren/project.sx")
+(load "lib/minikanren/intarith.sx")
+(load "lib/minikanren/matche.sx")
+(load "lib/minikanren/defrel.sx")
+(load "lib/commerce/catalog.sx")
+(epoch 2)
+(eval "(define ct-pass 0)")
+(eval "(define ct-fail 0)")
+(eval "(define ct-fails (list))")
+(eval "(define commerce-test (fn (name got expected) (if (= got expected) (set! ct-pass (+ ct-pass 1)) (begin (set! ct-fail (+ ct-fail 1)) (append! ct-fails name)))))")
+(epoch 3)
+(load "${file}")
+(epoch 4)
+(eval "(list ct-pass ct-fail)")
+(eval "ct-fails")
+EPOCHS
+
+  local OUTPUT
+  OUTPUT=$(timeout 300 "$SX_SERVER" < "$TMP" 2>/dev/null)
+  rm -f "$TMP"
+
+  # The (list ct-pass ct-fail) result follows its (ok-len 2 N) ack line.
+  local LINE
+  LINE=$(echo "$OUTPUT" | grep -oE '^\([0-9]+ [0-9]+\)$' | tail -1)
+  local P F
+  P=$(echo "$LINE" | sed -E 's/^\(([0-9]+) ([0-9]+)\)$/\1/')
+  F=$(echo "$LINE" | sed -E 's/^\(([0-9]+) ([0-9]+)\)$/\2/')
+  P=${P:-0}
+  F=${F:-0}
+  echo "${P} ${F}"
+}
+
+declare -A SUITE_PASS
+declare -A SUITE_FAIL
+TOTAL_PASS=0
+TOTAL_FAIL=0
+
+echo "Running commerce conformance suite..." >&2
+for s in "${SUITES[@]}"; do
+  read -r p f < <(run_suite "$s")
+  SUITE_PASS[$s]=$p
+  SUITE_FAIL[$s]=$f
+  TOTAL_PASS=$((TOTAL_PASS + p))
+  TOTAL_FAIL=$((TOTAL_FAIL + f))
+  printf "  %-12s %d/%d\n" "$s" "$p" "$((p+f))" >&2
+done
+
+{
+  printf '{\n'
+  printf '  "suites": {\n'
+  first=1
+  for s in "${SUITES[@]}"; do
+    if [ $first -eq 0 ]; then printf ',\n'; fi
+    printf '    "%s": {"pass": %d, "fail": %d}' "$s" "${SUITE_PASS[$s]}" "${SUITE_FAIL[$s]}"
+    first=0
+  done
+  printf '\n  },\n'
+  printf '  "total_pass": %d,\n' "$TOTAL_PASS"
+  printf '  "total_fail": %d,\n' "$TOTAL_FAIL"
+  printf '  "total": %d\n' "$((TOTAL_PASS + TOTAL_FAIL))"
+  printf '}\n'
+} > "$OUT_JSON"
+
+{
+  printf '# commerce Conformance Scoreboard\n\n'
+  printf '_Generated by `lib/commerce/conformance.sh`_\n\n'
+  printf '| Suite | Pass | Fail | Total |\n'
+  printf '|-------|-----:|-----:|------:|\n'
+  for s in "${SUITES[@]}"; do
+    p=${SUITE_PASS[$s]}
+    f=${SUITE_FAIL[$s]}
+    printf '| %s | %d | %d | %d |\n' "$s" "$p" "$f" "$((p+f))"
+  done
+  printf '| **Total** | **%d** | **%d** | **%d** |\n' "$TOTAL_PASS" "$TOTAL_FAIL" "$((TOTAL_PASS + TOTAL_FAIL))"
+} > "$OUT_MD"
+
+echo "Wrote $OUT_JSON and $OUT_MD" >&2
+echo "Total: $TOTAL_PASS pass, $TOTAL_FAIL fail" >&2
+
+[ "$TOTAL_FAIL" -eq 0 ]

lib/commerce/scoreboard.json

@@ -0,0 +1,8 @@
+{
+  "suites": {
+    "catalog": {"pass": 16, "fail": 0}
+  },
+  "total_pass": 16,
+  "total_fail": 0,
+  "total": 16
+}

lib/commerce/scoreboard.md

@@ -0,0 +1,8 @@
+# commerce Conformance Scoreboard
+
+_Generated by `lib/commerce/conformance.sh`_
+
+| Suite | Pass | Fail | Total |
+|-------|-----:|-----:|------:|
+| catalog | 16 | 0 | 16 |
+| **Total** | **16** | **0** | **16** |

lib/commerce/tests/catalog.sx

@@ -0,0 +1,93 @@
+;; lib/commerce/tests/catalog.sx — catalog facts + relational accessors.
+;; Uses (commerce-test name got expected) provided by conformance.sh.
+;; Query vars avoid the name `s` (the run-n macro binds `s` internally).
+
+(define
+  cat
+  (make-catalog
+    (list
+      (list "widget" 1000 :standard)
+      (list "gadget" 2500 :standard)
+      (list "book" 800 :zero-rated)
+      (list "tea" 1000 :reduced))
+    (list
+      (list "widget" :small -200)
+      (list "widget" :large 500)
+      (list "gadget" :std 0))
+    (list
+      (list "widget" :small 5)
+      (list "widget" :large 0)
+      (list "gadget" :std 12))))
+
+;; --- forward lookups ---
+
+(commerce-test
+  "price-forward"
+  (run* p (priceo cat "widget" p))
+  (list 1000))
+(commerce-test
+  "class-forward"
+  (run* c (classo cat "book" c))
+  (list :zero-rated))
+(commerce-test
+  "product-forward"
+  (run* q (fresh (p c) (producto cat "gadget" p c) (== q (list p c))))
+  (list (list 2500 :standard)))
+
+;; --- backward lookups (the showcase) ---
+
+(commerce-test
+  "sku-by-price-backward"
+  (run* sk (priceo cat sk 1000))
+  (list "widget" "tea"))
+
+(commerce-test
+  "sku-by-class-backward"
+  (run* sk (classo cat sk :standard))
+  (list "widget" "gadget"))
+
+(commerce-test
+  "all-prices"
+  (run* p (fresh (sk) (priceo cat sk p)))
+  (list 1000 2500 800 1000))
+
+;; --- variants + effective unit price ---
+
+(commerce-test
+  "variant-delta-forward"
+  (run* d (varianto cat "widget" :small d))
+  (list -200))
+
+(commerce-test
+  "unit-price-small"
+  (run* p (unit-priceo cat "widget" :small p))
+  (list 800))
+
+(commerce-test
+  "unit-price-large"
+  (run* p (unit-priceo cat "widget" :large p))
+  (list 1500))
+
+(commerce-test
+  "variant-by-delta-backward"
+  (run* v (varianto cat "widget" v -200))
+  (list :small))
+
+;; --- stock ---
+
+(commerce-test
+  "stock-forward"
+  (run* q (stocko cat "widget" :small q))
+  (list 5))
+
+(commerce-test
+  "in-stock-skus-backward"
+  (run* sk (fresh (v q) (stocko cat sk v q) (lto-i 0 q)))
+  (list "widget" "gadget"))
+
+;; --- deterministic helpers ---
+
+(commerce-test "catalog-price-helper" (catalog-price cat "gadget") 2500)
+(commerce-test "catalog-class-helper" (catalog-class cat "tea") :reduced)
+(commerce-test "catalog-has-yes" (catalog-has? cat "book") true)
+(commerce-test "catalog-has-no" (catalog-has? cat "nonesuch") false)

plans/commerce-on-sx.md

@@ -21,7 +21,7 @@ reconciliation — all auditable via the event log.
 
 ## Status (rolling)
 
-`bash lib/commerce/conformance.sh` → **0/0** (not yet started)
+`bash lib/commerce/conformance.sh` → **16/16** (1 suite: catalog)
 
 ## Ground rules
 
@@ -55,7 +55,7 @@ lib/commerce/api.sx ── (commerce/add) (commerce/total) (commerce/checkout)
 ```
 
 ## Phase 1 — Catalog + cart + deterministic totals
-- [ ] `catalog.sx` — product/variant/stock as facts
+- [x] `catalog.sx` — product/variant/stock as facts
 - [ ] `cart.sx` — line items, add/remove/qty
 - [ ] `price.sx` — base pricing relation, subtotal; tax
 - [ ] `api.sx` + tests + scoreboard + conformance.sh
@@ -76,7 +76,13 @@ lib/commerce/api.sx ── (commerce/add) (commerce/total) (commerce/checkout)
 - [ ] tests: webhook replay, partial refund, double-charge guard
 
 ## Progress log
-(loop fills this in)
+- 2026-06-06 — `catalog.sx`: catalog snapshot (products/variants/stock as fact
+  tuples) + multidirectional accessor relations (`producto`/`varianto`/`stocko`,
+  derived `priceo`/`classo`/`unit-priceo`) + deterministic `catalog-price`/
+  `-class`/`-has?` helpers. `conformance.sh` harness + scoreboard. catalog suite
+  16/16. Gotcha: minikanren `run-n` macro binds `s` internally — query vars must
+  avoid `s`; tests compare reified results with `=` (not `equal?`, which fails on
+  reified lists). Money = integer minor units throughout.
 
 ## Blockers
-(loop fills this in)
+(none)