veza/apps/web/src/hooks/useLocalStorage.test.ts

import { renderHook, act } from '@testing-library/react';
import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import { useLocalStorage } from './useLocalStorage';

// Mock localStorage
const localStorageMock = {
  getItem: vi.fn(),
  setItem: vi.fn(),
  removeItem: vi.fn(),
  clear: vi.fn(),
};

Object.defineProperty(window, 'localStorage', {
  value: localStorageMock,
});

describe('useLocalStorage', () => {
  beforeEach(() => {
    vi.clearAllMocks();
  });

  it('should return initial value when localStorage is empty', () => {
    localStorageMock.getItem.mockReturnValue(null);

    const { result } = renderHook(() =>
      useLocalStorage('test-key', 'default-value'),
    );

    expect(result.current[0]).toBe('default-value');
  });

  it('should return stored value from localStorage', () => {
    localStorageMock.getItem.mockReturnValue(JSON.stringify('stored-value'));

    const { result } = renderHook(() =>
      useLocalStorage('test-key', 'default-value'),
    );

    expect(result.current[0]).toBe('stored-value');
  });

  it('should update localStorage when value changes', () => {
    localStorageMock.getItem.mockReturnValue(null);

    const { result } = renderHook(() =>
      useLocalStorage('test-key', 'default-value'),
    );

    act(() => {
      result.current[1]('new-value');
    });

    expect(localStorageMock.setItem).toHaveBeenCalledWith(
      'test-key',
      JSON.stringify('new-value'),
    );
    expect(result.current[0]).toBe('new-value');
  });

  it('should handle object values', () => {
    const testObject = { name: 'test', value: 123 };
    localStorageMock.getItem.mockReturnValue(JSON.stringify(testObject));

    const { result } = renderHook(() => useLocalStorage('test-key', {}));

    expect(result.current[0]).toEqual(testObject);
  });
});