test(not-found): add 404 page tests

Author: Vishvadharman

app/not-found.test.tsx

@@ -0,0 +1,52 @@
+import { describe, expect, it, vi } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import NotFound from './not-found';
+
+vi.mock('next/link', () => ({
+  default: ({ href, children, ...props }: { href: string; children: React.ReactNode }) => (
+    <a href={href} {...props}>
+      {children}
+    </a>
+  ),
+}));
+
+describe('NotFound', () => {
+  it('renders without crashing', () => {
+    render(<NotFound />);
+
+    expect(document.body).toBeTruthy();
+  });
+
+  it('renders the oops text', () => {
+    render(<NotFound />);
+
+    expect(screen.getAllByText('𝒐𝒐𝒑𝒔')).toHaveLength(2);
+  });
+
+  it('renders git checkout main text', () => {
+    render(<NotFound />);
+
+    expect(screen.getByText(/git checkout main/i)).toBeTruthy();
+  });
+
+  it('renders go back home link with root href', () => {
+    render(<NotFound />);
+
+    const homeLink = screen.getByRole('link', {
+      name: /go back home/i,
+    });
+
+    expect(homeLink.getAttribute('href')).toBe('/');
+  });
+
+  it('renders github link pointing to commitpulse repository', () => {
+    render(<NotFound />);
+
+    const githubLink = screen.getByRole('link', {
+      name: /git checkout main/i,
+    });
+
+    expect(githubLink.getAttribute('href')).toContain('github.com');
+    expect(githubLink.getAttribute('href')).toContain('commitpulse');
+  });
+});