Give the demo data and the listing form their own tests, and stop loops that could run forever

TODO.md

@@ -128,17 +128,9 @@ decision, not a patch. Starting points: the dates.ts restructure in this PR;
 `scripts/mutation/execution.ts` for the test stage the decision would live in.
 
 The follow-up sweep bounded the freeze-capable loops across the rest of `src/`
-(`range`/`entries`/`chunk`/`reduce` shapes; see the `#fp` `range` helper). Two
-files were left out because they have **no mirror direct test suite at all**, so
-the mutation gate cannot even start on them — each needs its suite built first,
-then the same bounded-loop treatment:
-
-- `src/features/admin/listings-form.ts` — `parseDayPricesFromForm`'s
-  `for (let n = 1; n <= maxDays; n++)` spins forever under `n++ → n--` (blank
-  day-price reads skip without ever ending the loop).
-- `src/shared/seeds.ts` — the unique-slug count loop and the chunked attendee
-  loop both spin or grow without bound under a step-neutralising mutant
-  (`i++ → i--`, `offset += CHUNK_SIZE → /=`).
+(`range`/`entries`/`chunk`/`reduce` shapes; see the `#fp` `range` helper),
+including the two files that first needed mirror direct suites built
+(`src/features/admin/listings-form.ts`, `src/shared/seeds.ts`).
 
 ---
 

scripts/mutation/equivalent-mutants/features.txt

@@ -171,3 +171,13 @@ src/features/public/order.ts::loadOrderPools~15mruqs  1 → 0   # every listing'
 src/features/public/order.ts::bookingUrlFor.chosen.kind~17n3p4g   → "mutated"   # a selection key is always built as kind:id by listingOptionKey/packageOptionKey, so the kind is never missing
 src/features/public/order.ts::bookingUrlFor.chosen.rawId~1xqr8m1   → "mutated"   # the same key always carries its id, so the id half is never missing
 src/features/public/order.ts::bookingUrlFor.chosen.prefill~1vgmybj  1 → 0   # buildTicketListing sets maxPurchasable to 0 for a sold-out or closed listing and to at least 1 otherwise (max_quantity is at least 1), so the two thresholds never disagree once the checks beside them have passed
+
+# Listing form (listings-form.ts) — a redundant day-price row the parser drops,
+# a default the field's own bounds make unreachable, error text no surface can
+# show, and a fallback whose left side is never falsy-but-present.
+src/features/admin/listings-form.ts::parseDayPricesFromForm~11szepb  1 → 0   # reading day_price_0 as well changes nothing: parseDayPrices keeps only whole day counts of 1 or more
+src/features/admin/listings-form.ts::extractCommonFields.durationDays~1nsjfgg  ?? → ||   # duration_days is a number field with min 1 whose validate rejects anything below 1, so the value here is a positive number or absent
+src/features/admin/listings-form.ts::extractCommonFields.unitPrice~0fxriin  ?? → ||   # the only falsy non-null price is 0, and unit_price is a withDefault(() => 0) column, so the undefined the mutant produces is stored as that same 0
+src/features/admin/listings-form.ts::extractCommonFields.closesAt~1ox85dk  closes_at → ""   # the label only appears in normalizeDatetime's throw, and the field's validateDatetime already refused every value localToUtc would reject
+src/features/admin/listings-form.ts::extractCommonFields.date~1ogjyd0  date → ""   # same: the date field is validated by the same parser before toInput runs, so the throw naming it is unreachable
+src/features/admin/listings-form.ts::listingValidate~19dmftv  ?? → ||   # validateDayPricesFromForm returns null or one fixed non-empty message, so it is never falsy-but-present

scripts/mutation/equivalent-mutants/shared-a-l.txt

@@ -25,7 +25,7 @@ src/shared/qr-token.ts::buildQrBookPayload.d~1ywzxp9  ?? → ||   # input.date?:
 src/shared/qr-token.ts::buildQrBookPayload.n~1tn44vm  ?? → ||   # input.name?: string, only falsy string "" === fallback ""
 src/shared/app-forms.ts::createAuthedHandler~1q900po  ?? → ||   # config.auth is an AuthPolicy object when present, so it is always truthy
 src/shared/site-assignment.ts::renewalDeadlineBaseMs~00cywnq  ?? → ||   # parseReadOnlyFromMs(): number|null, 0 ?? 0 === 0 || 0
-src/shared/site-assignment.ts::assignSitesForEntries.site~101ljxt  ?? → ||   # available[idx]: BuiltSite|undefined, and a BuiltSite object is always truthy
+src/shared/site-assignment.ts::assignSitesForEntries.site~0c03jq6  ?? → ||   # available.pop(): BuiltSite|undefined, and a BuiltSite object is always truthy
 src/shared/site-assignment.ts::sendSiteAssignmentEmail.config~11vz7t9  ?? → ||   # getEmailConfig(): EmailConfig|null
 src/shared/site-assignment.ts::sendSiteAssignmentEmail.replyTo~195nl86  ?? → ||   # parseEmail(): ValidEmail|null, always truthy or null
 src/shared/ledger/project.ts::allBalances.add~0gr4ng6  ?? → ||   # allBalances: Map<string,number>.get; the only falsy-non-null number is 0, and 0 ?? 0 === 0 || 0
@@ -178,12 +178,10 @@ src/shared/band-name-generator.ts::fixArticles~1rw9fca  A $1 → "A $1 mutated"
 # parsePositiveIntId's strict decimal-digit schema.
 src/shared/logistics-filter.ts::parseAgentFilter.n~03f157n   → "mutated"   # parsePositiveIntId's schema rejects any non-digit string identically; the "" fallback and any mutated string both parse to null
 
-# crypto/der.ts — these values are written into Uint8Array elements. Adding or
+# crypto/der.ts — this value is written into a Uint8Array element. Adding or
 # subtracting 128 produces the same low eight bits, and Uint8Array discards all
-# higher bits. The base-128 continuation byte is therefore identical either way.
+# higher bits.
 src/shared/crypto/der.ts::encodeLength~0ikcwcz  128 → -128   # DER long-length marker: 128+n and -128+n have identical low eight bits
-src/shared/crypto/der.ts::encodeBase128~1em6brp  + → -   # base-128 continuation: low7+128 and low7-128 have identical low eight bits
-src/shared/crypto/der.ts::encodeBase128~1em6brp  128 → -128   # base-128 continuation marker is unchanged after Uint8Array conversion
 
 # dates.ts — provably-equivalent survivors from the whole-file run over the
 # dates suites. Each is unobservable through every export that reaches the line.

scripts/mutation/equivalent-mutants/shared-m-z.txt

@@ -261,3 +261,7 @@ src/shared/schema-atlas/types.ts::atlasState.facts~0j1zyry ?? → ||   # extra.f
 # data), so no caller, page, or log can ever see this string — no input
 # distinguishes it from "".
 src/shared/payment/row-state.ts::SortedAttendeeIdsSchema~1d17kt9  Refund claim attendee ids must be sorted and unique → ""   # issue text is discarded by the stored-JSON wrapper; unobservable through any surface
+
+# seeds.ts — two thresholds no seeded value can fall between.
+src/shared/seeds.ts::prepareAttendee.paymentId~01ncynu  0 → 1   # a seeded listing's unit price is 0 or one of the demo prices (500 and up), so no listing sits between the two thresholds
+src/shared/seeds.ts::createSeeds~0ghuowu  0 → 1   # the customisable listing always yields a delete plus one multi-row insert, so the list holds 0 or 2 statements, never 1

src/features/admin/listings-form.ts

@@ -7,6 +7,7 @@
  */
 
 /* jscpd:ignore-start */
+import { range } from "#fp";
 import { projectCatalogFields } from "#shared/catalog-fields/definition.ts";
 import {
   type ListingInput,
@@ -94,7 +95,7 @@ export const parseGroupIds = (form: FormParams): number[] =>
   form
     .getAll("group_ids")
     .map(Number)
-    .filter((n) => n > 0);
+    .filter((n) => Number.isSafeInteger(n) && n > 0);
 
 /**
  * Read the per-day-count price inputs (`day_price_1`, `day_price_2`, …) from
@@ -107,7 +108,7 @@ const parseDayPricesFromForm = (
   maxDays: number,
 ): DayPrices => {
   const result: DayPrices = {};
-  for (let n = 1; n <= maxDays; n++) {
+  for (const n of range(1, maxDays + 1)) {
     // Optional per-day price: blank ⇒ skip (that day isn't offered). A non-blank
     // value that fails to parse is caught by validateDayPricesFromForm before
     // the save, so here a null result is only ever a blank.

src/shared/bunny-cdn.ts

@@ -5,6 +5,7 @@
  * The pull zone is discovered via the Edge Script API, not request hostname.
  */
 
+import { range } from "#fp";
 import {
   getBunnyApiKey,
   getBunnyDnsSubdomainSuffix,
@@ -373,11 +374,8 @@ const registerBunnySubdomainImpl = async (
   // 3. Register hostname with pull zone (add hostname + SSL)
   //    Retry to allow DNS propagation after CNAME record creation.
   let cdnResult = await bunnyCdnApi.validateCustomDomain(fullDomain);
-  for (
-    let attempt = 0;
-    attempt < CERT_RETRY_COUNT && !cdnResult.ok;
-    attempt++
-  ) {
+  for (const attempt of range(0, CERT_RETRY_COUNT)) {
+    if (cdnResult.ok) break;
     await bunnyCdnApi.delay(certRetryDelay(attempt));
     cdnResult = await bunnyCdnApi.validateCustomDomain(fullDomain);
   }

src/shared/crypto/der.ts

@@ -23,17 +23,10 @@ export const bytesEqual = (left: Uint8Array, right: Uint8Array): boolean =>
   left.length === right.length &&
   left.every((byte, index) => byte === right[index]);
 
-const unsignedBytes = (value: number): number[] => {
-  const bytes: number[] = [];
-  for (
-    let remaining = value;
-    remaining > 0;
-    remaining = Math.floor(remaining / 256)
-  ) {
-    bytes.unshift(remaining & 0xff);
-  }
-  return bytes;
-};
+/** Big-endian bytes of a non-negative whole number; zero is no bytes. Each
+ * step shrinks the value 256-fold, so the recursion always bottoms out. */
+const unsignedBytes = (value: number): number[] =>
+  value <= 0 ? [] : [...unsignedBytes(Math.floor(value / 256)), value & 0xff];
 
 const encodeLength = (length: number): Uint8Array => {
   // Values below 128 use one byte. Otherwise bit 7 marks how many

src/shared/seeds.ts

@@ -3,7 +3,7 @@
  * Uses batch writes for efficient database operations.
  */
 
-import { map, sum } from "#fp";
+import { chunk, map, range, sum } from "#fp";
 import { encrypt } from "#shared/crypto/encryption.ts";
 import { hmacHash } from "#shared/crypto/hashing.ts";
 import { generateTicketToken } from "#shared/crypto/utils.ts";
@@ -40,16 +40,16 @@ const randomQuantity = (): number => 1 + Math.floor(Math.random() * 4);
 /** Sample unit prices in minor units (e.g. pence/cents) for paid listings */
 const DEMO_UNIT_PRICES = [500, 1000, 1500, 2000, 2500, 3000, 5000];
 
-/** Generate slugs that are unique within the batch */
+/** Generate slugs that are unique within the batch. The slugs made so far are
+ * the only "already taken" list — nothing is in the database yet. */
 const generateUniqueSlugs = async (count: number): Promise<SlugWithIndex[]> => {
-  const usedSlugs = new Set<string>();
   const results: SlugWithIndex[] = [];
-  for (let i = 0; i < count; i++) {
-    const result = await generateUniqueSlug(hmacHash, (slug) =>
-      Promise.resolve(usedSlugs.has(slug)),
+  for (const _slot of range(0, count)) {
+    results.push(
+      await generateUniqueSlug(hmacHash, (slug) =>
+        Promise.resolve(results.some((made) => made.slug === slug)),
+      ),
     );
-    usedSlugs.add(result.slug);
-    results.push(result);
   }
   return results;
 };
@@ -187,7 +187,10 @@ export const createSeeds = async (
       index: i,
       quantities,
       slug: slugs[i]!,
-      unitPrice: i % 2 === 0 ? randomChoice(DEMO_UNIT_PRICES) : 0,
+      // Paid listings walk the sample prices in order, so a big enough demo
+      // set shows every tier and a test can name each one.
+      unitPrice:
+        i % 2 === 0 ? DEMO_UNIT_PRICES[(i / 2) % DEMO_UNIT_PRICES.length]! : 0,
     };
   });
 
@@ -232,17 +235,15 @@ export const createSeeds = async (
   for (const [e, listingId] of listingIds.entries()) {
     const { quantities, unitPrice } = listingData[e]!;
 
-    for (let offset = 0; offset < attendeesPerListing; offset += CHUNK_SIZE) {
-      const batchSize = Math.min(CHUNK_SIZE, attendeesPerListing - offset);
-      const chunkQuantities = quantities.slice(offset, offset + batchSize);
+    for (const chunkQuantities of chunk(CHUNK_SIZE)(quantities)) {
       const statementPairs = await Promise.all(
         map((q: number) => prepareAttendee(listingId, q, unitPrice))(
           chunkQuantities,
         ),
       );
       // Each booking locates its attendee by the caller-supplied stable token.
       await executeBatch(statementPairs.flat());
-      totalAttendees += batchSize;
+      totalAttendees += chunkQuantities.length;
     }
   }