test(historical-trend-view): add theme contrast coverage

Author: Vishvadharman

components/dashboard/HistoricalTrendView.theme-contrast.test.tsx

@@ -0,0 +1,80 @@
+import { describe, it, expect, vi } from 'vitest';
+import { render, screen } from '@testing-library/react';
+import '@testing-library/jest-dom/vitest';
+
+import HistoricalTrendView from './HistoricalTrendView';
+import type { ActivityData } from '@/types/dashboard';
+import type { DashboardPeriod } from '@/utils/dashboardPeriod';
+
+vi.mock('next/navigation', () => ({
+  useRouter: () => ({
+    push: vi.fn(),
+  }),
+}));
+
+vi.mock('./Heatmap', () => ({
+  default: () => <div data-testid="heatmap">Heatmap</div>,
+}));
+
+const period: DashboardPeriod = {
+  kind: 'month',
+  month: '2025-05',
+  label: 'May 2025',
+  from: '2025-05-01T00:00:00.000Z',
+  to: '2025-05-31T23:59:59.999Z',
+};
+
+const activity: ActivityData[] = [
+  {
+    date: '2025-05-01',
+    count: 5,
+    intensity: 4,
+  },
+  {
+    date: '2025-05-02',
+    count: 2,
+    intensity: 2,
+  },
+];
+
+describe('HistoricalTrendView theme contrast', () => {
+  it('renders light mode background classes', () => {
+    const { container } = render(
+      <HistoricalTrendView username="tester" activity={activity} period={period} />
+    );
+
+    expect(container.innerHTML).toContain('bg-white');
+    expect(container.innerHTML).toContain('text-gray-900');
+  });
+
+  it('includes dark mode styling classes', () => {
+    const { container } = render(
+      <HistoricalTrendView username="tester" activity={activity} period={period} />
+    );
+
+    expect(container.innerHTML).toContain('dark:bg-[#0a0a0a]');
+    expect(container.innerHTML).toContain('dark:text-white');
+  });
+
+  it('renders text content with contrast-aware classes', () => {
+    render(<HistoricalTrendView username="tester" activity={activity} period={period} />);
+
+    expect(screen.getByText(/Explore long-term activity patterns/i)).toBeInTheDocument();
+
+    expect(screen.getByText(/Contributions/i)).toBeInTheDocument();
+  });
+
+  it('renders foreground content without clipping overlays', () => {
+    render(<HistoricalTrendView username="tester" activity={activity} period={period} />);
+
+    expect(screen.getByText(/Monthly Summary/i)).toBeInTheDocument();
+    expect(screen.getByText(/Yearly Summary/i)).toBeInTheDocument();
+  });
+
+  it('renders heatmap and statistics in both theme-capable layouts', () => {
+    render(<HistoricalTrendView username="tester" activity={activity} period={period} />);
+
+    expect(screen.getByTestId('heatmap')).toBeInTheDocument();
+    expect(screen.getByText(/Current Streak/i)).toBeInTheDocument();
+  });
+});