commerce: end-to-end composition integration suite (19 tests) — hardening

tests/integration.sx — one narrative across every module: catalog -> stock
check -> quote (promo+stack+tax) -> attribution -> order flow -> payment
envelope -> settle -> recon -> refund flow -> ledger mismatch, asserting the
seams tie together with consistent numbers. Proves the three-substrate
composition (minikanren pricing + flow lifecycle + persist ledger) end to end.
Total 297/297 across 18 suites.

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

lib/commerce/conformance.sh

@@ -17,7 +17,7 @@ if [ ! -x "$SX_SERVER" ]; then
   exit 1
 fi
 
-SUITES=(catalog cart price api promo stack quote ledger order recon federation attribution payment window nettax stock refund)
+SUITES=(catalog cart price api promo stack quote ledger order recon federation attribution payment window nettax stock refund integration)
 
 OUT_JSON="lib/commerce/scoreboard.json"
 OUT_MD="lib/commerce/scoreboard.md"

lib/commerce/scoreboard.json

@@ -16,9 +16,10 @@
     "window": {"pass": 19, "fail": 0},
     "nettax": {"pass": 11, "fail": 0},
     "stock": {"pass": 19, "fail": 0},
-    "refund": {"pass": 20, "fail": 0}
+    "refund": {"pass": 20, "fail": 0},
+    "integration": {"pass": 19, "fail": 0}
   },
-  "total_pass": 278,
+  "total_pass": 297,
   "total_fail": 0,
-  "total": 278
+  "total": 297
 }

lib/commerce/scoreboard.md

@@ -21,4 +21,5 @@ _Generated by `lib/commerce/conformance.sh`_
 | nettax | 11 | 0 | 11 |
 | stock | 19 | 0 | 19 |
 | refund | 20 | 0 | 20 |
-| **Total** | **278** | **0** | **278** |
+| integration | 19 | 0 | 19 |
+| **Total** | **297** | **0** | **297** |

lib/commerce/tests/integration.sx

@@ -0,0 +1,104 @@
+;; lib/commerce/tests/integration.sx — end-to-end composition proof.
+;; Uses (commerce-test name got expected) provided by conformance.sh.
+;;
+;; One narrative across every module: catalog → stock check → quote
+;; (promo+stack+tax) → order flow → payment envelope → settle → recon → refund.
+;; Proves the seams tie together with consistent numbers (the project's thesis:
+;; minikanren pricing + flow lifecycle + persist ledger compose).
+;; Builds one flow env with BOTH the order and refund flows.
+
+(define env (order-make-env))
+(define _rf (refund-flow-load! env))
+(define b (persist/mem-backend))
+
+(define
+  cat
+  (make-catalog
+    (list
+      (list "widget" 1000 :standard)
+      (list "book" 800 :zero-rated))
+    (list (list "widget" :small -200))
+    (list (list "widget" :small 10) (list "book" :none 5))))
+
+(define
+  rules
+  (list
+    (list :uk :standard :guest 2000)
+    (list :uk :zero-rated :guest 0)))
+
+(define ctx (make-pricing-context cat rules :uk :guest))
+
+(define
+  ruleset
+  (list
+    (list :percent "TEN" :standard 1000)
+    (list :fixed "FIVE" 0 50)))
+
+;; widget :small x2 → unit 800, extended 1600 (standard); book x1 → 800 (zero-rated)
+(define
+  cart
+  (list (list "widget" :small 2) (list "book" :none 1)))
+
+;; 1. stock gating passes (widget:small 10 >= 2)
+(commerce-test "int-can-reserve" (can-reserve? cat cart) true)
+
+;; 2. quote ties the whole pricing pipeline together
+;;    subtotal 2400; discount TEN 160 + FIVE 50 = 210; tax 1600@20% = 320;
+;;    total 2400 - 210 + 320 = 2510
+(define q (cart-quote ctx cart ruleset (list)))
+(commerce-test "int-quote-subtotal" (quote-subtotal q) 2400)
+(commerce-test "int-quote-discount" (quote-discount q) 210)
+(commerce-test "int-quote-tax" (quote-tax q) 320)
+(commerce-test "int-quote-total" (quote-total q) 2510)
+
+;; 3. attribution explains where the discount landed
+(commerce-test
+  "int-attribution"
+  (codes-for-line ctx cart ruleset (list "widget" :small 2))
+  (list "TEN"))
+(commerce-test
+  "int-order-level"
+  (order-level-codes ctx cart ruleset)
+  (list "FIVE"))
+
+;; 4. order carries the quote total into the ledger; suspends at payment
+(define oid "INT-1")
+(define id (order-begin! env b oid 1000 q))
+(commerce-test "int-order-total-from-quote" (order-total b oid) 2510)
+(commerce-test "int-waiting-payment" (order-flow-waiting env id) "payment")
+
+;; 5. the payment envelope reflects the quoted total
+(commerce-test
+  "int-payment-envelope"
+  (payment-request b oid :GBP "https://shop/return")
+  {:order "INT-1" :amount 2510 :return-url "https://shop/return" :currency :GBP})
+
+;; 6. settle the quoted amount → reconciles exactly
+(commerce-test
+  "int-settled"
+  (order-settle! env b id oid "pay-int" 1002 2510)
+  :settled)
+(commerce-test "int-status-fulfilled" (order-status b oid) :fulfilled)
+(commerce-test "int-recon-ok" (order-recon b oid) :ok)
+
+;; 7. partial refund via its own flow → recon moves to underpaid
+(define rid (refund-begin! env b oid "rf-int" 2000 510))
+(commerce-test "int-refund-approve" (refund-approve! env rid) :approved)
+(commerce-test
+  "int-refund-settle"
+  (refund-settle! env b rid oid "rf-int" 2001 510)
+  :settled)
+(commerce-test
+  "int-refunded-amount"
+  (order-refunded-amount-of (order-events b oid))
+  510)
+(commerce-test "int-recon-after-refund" (order-recon b oid) :underpaid)
+
+;; 8. ledger reconciliation flags the now-mismatched order
+(commerce-test
+  "int-mismatch"
+  (mismatched-orders b)
+  (list (order-stream "INT-1")))
+
+;; 9. distinct flow ids for the order and the refund
+(commerce-test "int-distinct-flow-ids" (not (= id rid)) true)