fix(react): strict mode support (#742)

packages/react/src/utils/tests/use-destroy.test.tsx

@@ -0,0 +1,112 @@
+import { render, renderHook } from '@testing-library/react';
+import { StrictMode } from 'react';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { useDestroy } from '../use-destroy';
+
+describe('useDestroy', () => {
+  beforeEach(() => {
+    vi.useFakeTimers();
+  });
+
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  it('destroys instance after unmount', () => {
+    const instance = { destroy: vi.fn() };
+
+    const { unmount } = renderHook(() => useDestroy(instance));
+
+    expect(instance.destroy).not.toHaveBeenCalled();
+
+    unmount();
+    vi.runAllTimers();
+
+    expect(instance.destroy).toHaveBeenCalledOnce();
+  });
+
+  it('does not destroy synchronously in cleanup', () => {
+    const instance = { destroy: vi.fn() };
+
+    const { unmount } = renderHook(() => useDestroy(instance));
+
+    unmount();
+
+    // Destroy is deferred — not called yet
+    expect(instance.destroy).not.toHaveBeenCalled();
+
+    vi.runAllTimers();
+    expect(instance.destroy).toHaveBeenCalledOnce();
+  });
+
+  it('does not destroy in StrictMode double-mount', () => {
+    const instance = { destroy: vi.fn() };
+
+    function TestComponent() {
+      useDestroy(instance);
+      return null;
+    }
+
+    render(
+      <StrictMode>
+        <TestComponent />
+      </StrictMode>
+    );
+
+    vi.runAllTimers();
+
+    // StrictMode runs cleanup then re-mount — destroy should be cancelled
+    expect(instance.destroy).not.toHaveBeenCalled();
+  });
+
+  it('destroys after real unmount in StrictMode', () => {
+    const instance = { destroy: vi.fn() };
+
+    function TestComponent() {
+      useDestroy(instance);
+      return null;
+    }
+
+    const { unmount } = render(
+      <StrictMode>
+        <TestComponent />
+      </StrictMode>
+    );
+
+    vi.runAllTimers();
+    expect(instance.destroy).not.toHaveBeenCalled();
+
+    unmount();
+    vi.runAllTimers();
+
+    expect(instance.destroy).toHaveBeenCalledOnce();
+  });
+
+  it('calls setup once on mount', () => {
+    const instance = { destroy: vi.fn() };
+    const setup = vi.fn();
+
+    renderHook(() => useDestroy(instance, setup));
+
+    expect(setup).toHaveBeenCalledOnce();
+  });
+
+  it('calls setup once in StrictMode (skips re-mount)', () => {
+    const instance = { destroy: vi.fn() };
+    const setup = vi.fn();
+
+    function TestComponent() {
+      useDestroy(instance, setup);
+      return null;
+    }
+
+    render(
+      <StrictMode>
+        <TestComponent />
+      </StrictMode>
+    );
+
+    // Setup should only run once — the re-mount skips it
+    expect(setup).toHaveBeenCalledOnce();
+  });
+});