test: add unit tests for hooks (useBookmarks, useUpdateCheck)

- Export loadBookmarks/saveBookmarks and isNewer for testability
- Add 12 tests covering bookmark persistence and semver comparison
- Total: 165 tests passing

src/hooks/__tests__/useBookmarks.test.ts

@@ -0,0 +1,56 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+import { loadBookmarks, saveBookmarks, type Bookmark } from '../useBookmarks';
+
+const STORAGE_KEY = 'pinchchat-bookmarks';
+
+// Mock localStorage
+const store: Record<string, string> = {};
+const localStorageMock = {
+  getItem: vi.fn((key: string) => store[key] ?? null),
+  setItem: vi.fn((key: string, value: string) => { store[key] = value; }),
+  removeItem: vi.fn((key: string) => { delete store[key]; }),
+};
+
+Object.defineProperty(globalThis, 'localStorage', { value: localStorageMock });
+
+beforeEach(() => {
+  for (const key of Object.keys(store)) delete store[key];
+  vi.clearAllMocks();
+});
+
+describe('loadBookmarks', () => {
+  it('returns empty array when nothing stored', () => {
+    expect(loadBookmarks()).toEqual([]);
+  });
+
+  it('returns parsed bookmarks from localStorage', () => {
+    const bookmarks: Bookmark[] = [
+      { messageId: 'msg1', sessionKey: 'sess1', preview: 'Hello', timestamp: 1000, bookmarkedAt: 2000 },
+    ];
+    store[STORAGE_KEY] = JSON.stringify(bookmarks);
+    expect(loadBookmarks()).toEqual(bookmarks);
+  });
+
+  it('returns empty array on corrupt JSON', () => {
+    store[STORAGE_KEY] = '{broken';
+    expect(loadBookmarks()).toEqual([]);
+  });
+});
+
+describe('saveBookmarks', () => {
+  it('persists bookmarks to localStorage', () => {
+    const bookmarks: Bookmark[] = [
+      { messageId: 'msg1', sessionKey: 'sess1', preview: 'Test', timestamp: 1000, bookmarkedAt: 2000 },
+    ];
+    saveBookmarks(bookmarks);
+    expect(JSON.parse(store[STORAGE_KEY]!)).toEqual(bookmarks);
+  });
+
+  it('overwrites existing bookmarks', () => {
+    saveBookmarks([{ messageId: 'old', sessionKey: 's', preview: '', timestamp: 0, bookmarkedAt: 0 }]);
+    saveBookmarks([{ messageId: 'new', sessionKey: 's', preview: '', timestamp: 0, bookmarkedAt: 0 }]);
+    const stored = JSON.parse(store[STORAGE_KEY]!);
+    expect(stored).toHaveLength(1);
+    expect(stored[0].messageId).toBe('new');
+  });
+});

src/hooks/__tests__/useUpdateCheck.test.ts

@@ -0,0 +1,33 @@
+import { describe, it, expect } from 'vitest';
+import { isNewer } from '../useUpdateCheck';
+
+describe('isNewer', () => {
+  it('returns true when remote major is higher', () => {
+    expect(isNewer('2.0.0', '1.0.0')).toBe(true);
+  });
+
+  it('returns true when remote minor is higher', () => {
+    expect(isNewer('1.5.0', '1.4.0')).toBe(true);
+  });
+
+  it('returns true when remote patch is higher', () => {
+    expect(isNewer('1.4.2', '1.4.1')).toBe(true);
+  });
+
+  it('returns false when versions are equal', () => {
+    expect(isNewer('1.4.1', '1.4.1')).toBe(false);
+  });
+
+  it('returns false when remote is older', () => {
+    expect(isNewer('1.3.9', '1.4.0')).toBe(false);
+  });
+
+  it('handles missing patch segments', () => {
+    expect(isNewer('1.1', '1.0.9')).toBe(true);
+  });
+
+  it('handles large version numbers', () => {
+    expect(isNewer('1.66.1', '1.66.0')).toBe(true);
+    expect(isNewer('1.66.0', '1.66.1')).toBe(false);
+  });
+});

src/hooks/useBookmarks.ts

@@ -10,7 +10,7 @@ export interface Bookmark {
   bookmarkedAt: number;
 }
 
-function loadBookmarks(): Bookmark[] {
+export function loadBookmarks(): Bookmark[] {
   try {
     const raw = localStorage.getItem(STORAGE_KEY);
     if (raw) return JSON.parse(raw) as Bookmark[];
@@ -18,7 +18,7 @@ function loadBookmarks(): Bookmark[] {
   return [];
 }
 
-function saveBookmarks(bookmarks: Bookmark[]) {
+export function saveBookmarks(bookmarks: Bookmark[]) {
   try {
     localStorage.setItem(STORAGE_KEY, JSON.stringify(bookmarks));
   } catch { /* noop */ }

src/hooks/useUpdateCheck.ts

@@ -54,7 +54,7 @@ export function useUpdateCheck(currentVersion: string): UpdateInfo {
 }
 
 /** True if remote is newer than local (semver compare) */
-function isNewer(remote: string, local: string): boolean {
+export function isNewer(remote: string, local: string): boolean {
   const r = remote.split('.').map(Number);
   const l = local.split('.').map(Number);
   for (let i = 0; i < 3; i++) {