fix: repair cross-package rename, icon-only button label, date format, and sort toggle

- api.ts: import renamed useDebounce hook instead of removed useThrottle
- Button: apply aria-label for icon-only buttons (WCAG 2.2 SC 4.1.2)
- date.ts: format as D/MM/YYYY (unpadded day) via formatToParts for en-AU
- DataTable: use functional setState to fix stale-closure sort-direction toggle
- tsconfig: add bun-types to resolve bun:test module in test files

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 an app-specific alias
+export { useDebounce as useSearchDebounce }

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

@@ -17,13 +17,13 @@ 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.
+ * Icon-only buttons render no visible text, so they must carry an explicit
+ * accessible name (WCAG 2.2 SC 4.1.2 Name, Role, Value). `aria-label` is applied to
+ * the element when provided; when `iconOnly` is set without one, a fallback is
+ * emitted and a development-mode warning flags the missing label at the call site.
  *
- * 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.
+ * Text buttons intentionally receive no `aria-label` — their visible text is already
+ * the accessible name, and labelling them would override it.
  */
 export function Button({
   children,
@@ -34,13 +34,25 @@ export function Button({
   onClick,
   "aria-label": ariaLabel,
 }: Props) {
+  // Prefer the caller's label; for icon-only buttons fall back to string children so
+  // the element always exposes an accessible name. Text buttons resolve to undefined,
+  // which React omits entirely, leaving the visible text as the accessible name.
+  const resolvedAriaLabel =
+    ariaLabel ?? (iconOnly ? (typeof children === "string" ? children : "Button") : undefined)
+
+  if (process.env.NODE_ENV !== "production" && iconOnly && !ariaLabel) {
+    console.warn(
+      "Button: `iconOnly` buttons require an `aria-label` for screen reader users (WCAG 2.2 SC 4.1.2). " +
+        `Falling back to "${resolvedAriaLabel}".`,
+    )
+  }
+
   return (
     <button
       className={`btn btn-${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={resolvedAriaLabel}
     >
       {icon && <span className="btn-icon">{icon}</span>}
       {!iconOnly && children}

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

@@ -16,22 +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.
+ * The direction toggle uses the functional form of `setSortDir` so it reads the
+ * latest committed value rather than the one captured when the handler was created.
+ * This matters under React 18 automatic batching: two clicks flushed in a single
+ * render would otherwise both read the same `sortDir` and collapse into one toggle.
  */
 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")
 
-  // 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
+      setSortDir((prev) => (prev === "asc" ? "desc" : "asc"))
     } else {
       setSortKey(key)
       setSortDir("asc")

packages/utils/src/format/date.ts

@@ -1,21 +1,26 @@
 /**
  * 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.
+ * Note on `formatDate`: `Intl.DateTimeFormat` ignores the order in which options are
+ * declared and uses the locale's own field ordering, so `en-AU` is always day-first.
+ * It does, however, coerce `day: "numeric"` to `2-digit`, producing a zero-padded day
+ * ("01/03/2024"). The contract here is D/MM/YYYY — unpadded day, 4-digit year — so the
+ * string is assembled from `formatToParts` rather than taken from `format` directly.
  *
- * 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.
+ * `dateStyle: "short"` is deliberately not used: it would drop the year to 2 digits
+ * ("1/3/24").
  */
 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",
+  const parts = new Intl.DateTimeFormat("en-AU", {
     day: "numeric",
+    month: "2-digit",
     year: "numeric",
-  }).format(date)
+  }).formatToParts(date)
+
+  const get = (type: Intl.DateTimeFormatPartTypes) =>
+    parts.find((p) => p.type === type)?.value ?? ""
+
+  return `${Number(get("day"))}/${get("month")}/${get("year")}`
 }
 
 export function formatDateTime(date: Date): string {

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"]