Added keyboard navigation tests for Combobox

Author: Maitri-shah29

apps/desktop/src/tests/Combobox.test.tsx

@@ -0,0 +1,50 @@
+import { render, screen } from '@testing-library/react';
+import '@testing-library/jest-dom/vitest';
+import userEvent from '@testing-library/user-event';
+import { describe, it, expect, vi } from 'vitest';
+import { Combobox } from '../components/ui/Select';
+
+describe('Combobox keyboard interactions', () => {
+  const options = [
+    { value: '1', label: 'One' },
+    { value: '2', label: 'Two' },
+    { value: '3', label: 'Three' },
+  ];
+
+  it('opens with ArrowDown/Enter and lets you search, commit custom entry with Enter', async () => {
+    const onChange = vi.fn();
+    const user = userEvent.setup();
+    render(<Combobox options={options} value={''} onChange={onChange} />);
+
+    const trigger = screen.getByRole('combobox');
+
+    await user.click(trigger);
+
+    expect(trigger).toHaveAttribute('aria-expanded', 'true');
+
+    const input = screen.getByRole('textbox');
+    await user.type(input, 'CustomName');
+
+    await user.keyboard('{Enter}');
+    expect(onChange).toHaveBeenCalledWith('CustomName');
+  });
+
+  it('navigates filtered options with Arrow keys and selects with Enter', async () => {
+    const onChange = vi.fn();
+    const user = userEvent.setup();
+    render(<Combobox options={options} value={''} onChange={onChange} />);
+
+    const trigger = screen.getByRole('combobox');
+    await user.click(trigger);
+
+    const input = screen.getByRole('textbox');
+    await user.type(input, 'T');
+
+    await user.keyboard('{ArrowDown}');
+    const two = screen.getByRole('option', { name: 'Two' });
+    expect(two).toHaveFocus();
+
+    await user.keyboard('{Enter}');
+    expect(onChange).toHaveBeenCalledWith('Two');
+  });
+});