Merge branch 'main' into fix/debounce-preview-requests-clean

Author: chavanGaneshDatta

app/components/ScrollRestoration.empty-fallback.test.tsx

@@ -0,0 +1,62 @@
+import { render } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+
+import ScrollRestoration from './ScrollRestoration';
+
+const mockUsePathname = vi.fn();
+
+vi.mock('next/navigation', () => ({
+  usePathname: () => mockUsePathname(),
+}));
+
+describe('ScrollRestoration empty fallback behavior', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    sessionStorage.clear();
+    mockUsePathname.mockReturnValue('/');
+    window.scrollTo = vi.fn();
+  });
+
+  it('renders null without crashing when no saved scroll position exists', () => {
+    const { container } = render(<ScrollRestoration />);
+
+    expect(container.firstChild).toBeNull();
+  });
+
+  it('does not scroll when sessionStorage has no saved position', () => {
+    render(<ScrollRestoration />);
+
+    expect(window.scrollTo).not.toHaveBeenCalled();
+  });
+
+  it('restores saved scroll position when value exists', () => {
+    sessionStorage.setItem('scroll-position-/', '250');
+
+    render(<ScrollRestoration />);
+
+    expect(window.scrollTo).toHaveBeenCalledWith(0, 250);
+  });
+
+  it('stores current scroll position on scroll event', () => {
+    Object.defineProperty(window, 'scrollY', {
+      value: 300,
+      configurable: true,
+    });
+
+    render(<ScrollRestoration />);
+
+    window.dispatchEvent(new Event('scroll'));
+
+    expect(sessionStorage.getItem('scroll-position-/')).toBe('300');
+  });
+
+  it('uses pathname-specific storage keys for empty fallback safety', () => {
+    mockUsePathname.mockReturnValue('/dashboard');
+
+    render(<ScrollRestoration />);
+
+    window.dispatchEvent(new Event('scroll'));
+
+    expect(sessionStorage.getItem('scroll-position-/dashboard')).toBeDefined();
+  });
+});