Add dependency-free browser test suite and README

49 tests run in headless Chrome via tests/run.sh: unit tests for the pure modules plus integration tests that drive the real page in an iframe (filtering, URL state, bag, limits, cross-tab sync, checkout, dialogs, accessibility and overflow checks).
2026-11-07 21:18:38 -07:00
parent 7d34ab22f8
commit eb101c3e05
10 changed files with 652 additions and 0 deletions
@@ -0,0 +1,102 @@
+import { PRODUCTS } from "../dist/js/catalog.js";
+import {
+  MAX_QTY,
+  STORAGE_KEY,
+  cartCount,
+  cartLines,
+  cartSubtotal,
+  changeQty,
+  loadCart,
+  sanitizeCart,
+  saveCart,
+} from "../dist/js/cart.js";
+import { assert, equal, test } from "./harness.js";
+
+const ids = PRODUCTS.map((p) => p.id);
+
+function fakeStorage(initial = {}) {
+  const data = { ...initial };
+  return {
+    data,
+    getItem: (k) => (k in data ? data[k] : null),
+    setItem: (k, v) => void (data[k] = String(v)),
+    removeItem: (k) => void delete data[k],
+  };
+}
+const broken = {
+  getItem() { throw new Error("blocked"); },
+  setItem() { throw new Error("quota"); },
+  removeItem() { throw new Error("blocked"); },
+};
+
+test("cart: the storage key is unchanged, so existing bags carry over", () => {
+  equal(STORAGE_KEY, "fieldwork-bag-v1");
+});
+
+test("cart: sanitizeCart keeps valid lines", () => {
+  equal(sanitizeCart({ pack: 2, mug: 1 }, ids), { pack: 2, mug: 1 });
+});
+
+test("cart: sanitizeCart drops invalid quantities and unknown products", () => {
+  const dirty = { pack: -3, mug: 0, cap: 1.5, bottle: "2", lantern: NaN, blanket: null, ghost: 4 };
+  equal(sanitizeCart(dirty, ids), {});
+  equal(sanitizeCart({ pack: Infinity }, ids), {});
+});
+
+test("cart: sanitizeCart clamps oversized quantities", () => {
+  equal(sanitizeCart({ pack: 500 }, ids), { pack: MAX_QTY });
+});
+
+test("cart: sanitizeCart rejects non-objects and cannot be prototype-polluted", () => {
+  for (const bad of [null, undefined, [], "x", 5, true]) equal(sanitizeCart(bad, ids), {});
+  const polluted = JSON.parse('{"__proto__":{"pack":3},"constructor":{"mug":2}}');
+  equal(sanitizeCart(polluted, ids), {});
+  assert(({}).pack === undefined, "Object.prototype untouched");
+});
+
+test("cart: changeQty adds, removes at zero, and clamps to the limit", () => {
+  let cart = changeQty({}, "pack", 1);
+  equal(cart, { pack: 1 });
+  cart = changeQty(cart, "pack", 1);
+  equal(cart, { pack: 2 });
+  cart = changeQty(cart, "pack", -2);
+  equal(cart, {}, "line removed at zero");
+  equal(changeQty({}, "pack", -1), {}, "cannot go negative");
+  equal(changeQty({ pack: MAX_QTY }, "pack", 1), { pack: MAX_QTY }, "limit holds");
+});
+
+test("cart: changeQty is immutable", () => {
+  const original = Object.freeze({ pack: 1 });
+  const next = changeQty(original, "mug", 1);
+  equal(original, { pack: 1 });
+  assert(next !== original);
+});
+
+test("cart: counts, lines and subtotal (exact, in cents, in catalogue order)", () => {
+  const cart = { mug: 2, pack: 1 }; // inserted out of catalogue order
+  equal(cartCount(cart), 3);
+  equal(cartLines(cart, PRODUCTS).map((l) => [l.product.id, l.qty, l.total]), [
+    ["pack", 1, 8600],
+    ["mug", 2, 4800],
+  ]);
+  equal(cartSubtotal(cart, PRODUCTS), 13400);
+  equal(cartSubtotal({}, PRODUCTS), 0);
+});
+
+test("cart: loadCart reads, sanitises, and survives bad storage", () => {
+  equal(loadCart(fakeStorage({ [STORAGE_KEY]: '{"pack":2}' }), ids), { pack: 2 });
+  equal(loadCart(fakeStorage({ [STORAGE_KEY]: "not json{" }), ids), {}, "corrupt JSON");
+  equal(loadCart(fakeStorage(), ids), {}, "nothing saved");
+  equal(loadCart(broken, ids), {}, "storage throws");
+  equal(loadCart(null, ids), {}, "storage unavailable");
+});
+
+test("cart: saveCart writes, clears when empty, and never throws", () => {
+  const storage = fakeStorage();
+  saveCart(storage, { pack: 1 });
+  equal(JSON.parse(storage.data[STORAGE_KEY]), { pack: 1 });
+  saveCart(storage, {});
+  assert(!(STORAGE_KEY in storage.data), "empty cart removes the key");
+  saveCart(broken, { pack: 1 });
+  saveCart(null, { pack: 1 });
+});