function createLocalStorageMock(): Storage { const store = new Map(); return { get length() { return store.size; }, clear() { store.clear(); }, getItem(key: string) { return store.has(key) ? (store.get(key) ?? null) : null; }, key(index: number) { return Array.from(store.keys())[index] ?? null; }, removeItem(key: string) { store.delete(key); }, setItem(key: string, value: string) { store.set(key, value); }, }; } const localStorageMock = createLocalStorageMock(); Object.defineProperty(globalThis, "localStorage", { configurable: true, value: localStorageMock, }); if (typeof window !== "undefined") { Object.defineProperty(window, "localStorage", { configurable: true, value: localStorageMock, }); }