test: add unit tests for useSendShortcut hook and @testing-library/react

src/hooks/__tests__/useSendShortcut.test.ts

@@ -0,0 +1,58 @@
+/**
+ * @vitest-environment jsdom
+ */
+import { describe, it, expect, beforeEach } from 'vitest';
+import { renderHook, act } from '@testing-library/react';
+import { useSendShortcut } from '../useSendShortcut';
+
+const STORAGE_KEY = 'pinchchat-send-on-enter';
+
+describe('useSendShortcut', () => {
+  beforeEach(() => {
+    localStorage.clear();
+  });
+
+  it('defaults to true when no stored preference', () => {
+    const { result } = renderHook(() => useSendShortcut());
+    expect(result.current.sendOnEnter).toBe(true);
+  });
+
+  it('reads stored "true" preference', () => {
+    localStorage.setItem(STORAGE_KEY, 'true');
+    const { result } = renderHook(() => useSendShortcut());
+    expect(result.current.sendOnEnter).toBe(true);
+  });
+
+  it('reads stored "false" preference', () => {
+    localStorage.setItem(STORAGE_KEY, 'false');
+    const { result } = renderHook(() => useSendShortcut());
+    expect(result.current.sendOnEnter).toBe(false);
+  });
+
+  it('toggles from true to false and persists', () => {
+    const { result } = renderHook(() => useSendShortcut());
+    expect(result.current.sendOnEnter).toBe(true);
+
+    act(() => result.current.toggle());
+
+    expect(result.current.sendOnEnter).toBe(false);
+    expect(localStorage.getItem(STORAGE_KEY)).toBe('false');
+  });
+
+  it('toggles from false to true and persists', () => {
+    localStorage.setItem(STORAGE_KEY, 'false');
+    const { result } = renderHook(() => useSendShortcut());
+
+    act(() => result.current.toggle());
+
+    expect(result.current.sendOnEnter).toBe(true);
+    expect(localStorage.getItem(STORAGE_KEY)).toBe('true');
+  });
+
+  it('toggle is stable across renders', () => {
+    const { result, rerender } = renderHook(() => useSendShortcut());
+    const firstToggle = result.current.toggle;
+    rerender();
+    expect(result.current.toggle).toBe(firstToggle);
+  });
+});