fix: repair DOM test harness, hook rename, date padding, a11y label and sort closure

- bunfig.toml: preload happy-dom setup from repo root (the 'environment'
  key is not a real Bun option and was silently ignored, so bare
  'bun test' had no DOM). Fixes 9 'document is not defined' failures.
- apps/web/src/lib/api.ts: hook renamed useThrottle -> useDebounce in
  @e2e/utils; fix import and useSearchDebounce re-export.
- packages/utils/src/format/date.ts: formatDate used en-AU which hard-pads
  the day (01/03/2024); switch to en-GB numeric day (1/03/2024).
- tsconfig.json: add bun-types to compilerOptions.types to resolve
  'Cannot find module bun:test'.
- Button.tsx: always emit an accessible name via aria-label for icon-only
  buttons, with a dev warning when none is supplied (WCAG 4.1.2).
- DataTable.tsx: unify sortKey/sortDir into one state object updated via a
  single functional updater, fixing the stale-closure sort toggle.

No test files or dependencies changed. bun test: 13/13 pass; tsc --noEmit clean.

Author: QuantCode Agent

apps/web/src/lib/api.ts

@@ -1,14 +1,8 @@
 /**
  * API client utilities for the web app.
- *
- * BUG: imports `useThrottle` from @e2e/utils, but that hook was renamed to
- * `useDebounce`. This causes a TypeScript error and a runtime crash.
- *
- * Fix: change the import to `useDebounce`.
  */
 
-// BUG: useThrottle no longer exists — was renamed to useDebounce
-import { useThrottle } from "@e2e/utils"
+import { useDebounce } from "@e2e/utils"
 import { formatDate, formatAUD } from "@e2e/utils"
 
 export const BASE_URL = process.env.API_URL ?? "http://localhost:3000"
@@ -28,5 +22,5 @@ export async function fetchPosts() {
 // Re-export formatting utilities used throughout the app
 export { formatDate, formatAUD }
 
-// Re-export the debounce hook (currently broken import)
-export { useThrottle as useSearchDebounce }
+// Re-export the debounce hook under the app-facing name
+export { useDebounce as useSearchDebounce }

bunfig.toml

@@ -1,2 +1,2 @@
 [test]
-environment = "happy-dom"
+preload = ["./packages/ui/test/setup.ts"]

packages/ui/src/components/Button/Button.tsx

@@ -17,13 +17,10 @@ type Props = {
 /**
  * Button component.
  *
- * BUG: When `iconOnly` is true, the button renders without visible text.
- * An `aria-label` is required for screen reader accessibility (WCAG 2.1 SC 4.1.2),
- * but the component does not enforce or warn about its absence.
- *
- * The test in Button.test.tsx checks that an icon-only button has an accessible name.
- * Fix: throw/warn in development when `iconOnly && !aria-label`, or always render
- * the aria-label attribute when iconOnly is true.
+ * Icon-only buttons render no visible text, so they always emit an `aria-label`
+ * to guarantee an accessible name (WCAG 2.2 SC 4.1.2 Name, Role, Value).
+ * A dev-only warning is logged when an icon-only button omits `aria-label`,
+ * since the fallback ("Button") is not a meaningful description.
  */
 export function Button({
   children,
@@ -34,13 +31,21 @@ export function Button({
   onClick,
   "aria-label": ariaLabel,
 }: Props) {
+  const resolvedLabel =
+    ariaLabel ?? (iconOnly ? (typeof children === "string" ? children : "Button") : undefined)
+
+  if (process.env.NODE_ENV !== "production" && iconOnly && !ariaLabel) {
+    console.warn(
+      "[Button] `iconOnly` buttons require an explicit `aria-label` to provide an accessible name (WCAG 2.2 SC 4.1.2). Falling back to a generic label.",
+    )
+  }
+
   return (
     <button
       className={`btn btn-${variant}`}
       disabled={disabled}
       onClick={onClick}
-      // BUG: aria-label is not applied when iconOnly is true and no ariaLabel is passed
-      // The component should enforce aria-label for icon-only buttons
+      aria-label={resolvedLabel}
     >
       {icon && <span className="btn-icon">{icon}</span>}
       {!iconOnly && children}

packages/ui/src/components/DataTable/DataTable.tsx

@@ -16,26 +16,18 @@ type Props<T extends Record<string, unknown>> = {
 /**
  * DataTable with client-side sorting.
  *
- * BUG: The sort handler has a stale closure — it captures `sortDir` at the
- * time the handler is created, so toggling sort direction does not work
- * correctly after the first click. The second click always sorts in the same
- * direction as the first.
- *
- * Fix: use the functional form of setState — `setSortDir(prev => ...)` —
- * so the toggle always reads the current value.
+ * Sort key and direction are held in a single state object and updated through
+ * one functional updater, so the toggle decision always reads the current
+ * (non-stale) state rather than the value captured when the handler was created.
  */
 export function DataTable<T extends Record<string, unknown>>({ data, columns }: Props<T>) {
-  const [sortKey, setSortKey] = useState<keyof T | null>(null)
-  const [sortDir, setSortDir] = useState<SortDir>("asc")
+  const [sort, setSort] = useState<{ key: keyof T | null; dir: SortDir }>({ key: null, dir: "asc" })
+  const { key: sortKey, dir: sortDir } = sort
 
-  // BUG: stale closure — sortDir is captured at handler creation time
   const handleSort = (key: keyof T) => {
-    if (sortKey === key) {
-      setSortDir(sortDir === "asc" ? "desc" : "asc") // BUG: reads stale sortDir
-    } else {
-      setSortKey(key)
-      setSortDir("asc")
-    }
+    setSort((prev) =>
+      prev.key === key ? { key, dir: prev.dir === "asc" ? "desc" : "asc" } : { key, dir: "asc" },
+    )
   }
 
   const sorted = sortKey

packages/utils/src/format/date.ts

@@ -1,19 +1,14 @@
 /**
  * Date formatting utilities.
  *
- * BUG: formatDate passes `'en-AU'` as the locale but then uses a US-style
- * format string option (`month: 'numeric'` before `day: 'numeric'`), which
- * produces MM/DD/YYYY output instead of DD/MM/YYYY for Australian dates.
- *
- * Fix: use `dateStyle: 'short'` with `'en-AU'` locale, which correctly
- * produces DD/MM/YYYY, or explicitly set `day: 'numeric', month: 'numeric', year: 'numeric'`
- * and rely on the locale to order them correctly.
+ * Produces day-first (D/MM/YYYY) output. Note that `en-AU` zero-pads the day
+ * regardless of `day: "numeric"`, yielding "01/03/2024"; `en-GB` honours the
+ * numeric day request and yields "1/03/2024" while keeping day-first ordering.
  */
 export function formatDate(date: Date): string {
-  // BUG: explicit field order overrides locale ordering — produces M/D/YYYY not D/M/YYYY
-  return new Intl.DateTimeFormat("en-AU", {
-    month: "numeric",
+  return new Intl.DateTimeFormat("en-GB", {
     day: "numeric",
+    month: "2-digit",
     year: "numeric",
   }).format(date)
 }

tsconfig.json

@@ -6,6 +6,7 @@
     "jsx": "react-jsx",
     "strict": true,
     "skipLibCheck": true,
+    "types": ["bun-types"],
     "paths": {
       "@e2e/ui": ["./packages/ui/src/index.ts"],
       "@e2e/utils": ["./packages/utils/src/index.ts"]