Add additional unit tests

src/components/ProductRow.test.tsx

@@ -1,4 +1,5 @@
 import { render, screen } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
 import { describe, expect, it, vi } from 'vitest';
 import { ProductRow } from './ProductRow';
 import { Product } from '../models/Product';
@@ -32,4 +33,62 @@ describe('ProductRow', () => {
     expect(screen.getByText(/Barcode: 123456/)).toBeInTheDocument();
     expect(screen.queryByText(/bottle/i)).not.toBeInTheDocument();
   });
+
+  it('saves edits and closes the form', async () => {
+    const user = userEvent.setup();
+    const onSave = vi.fn();
+
+    render(
+      <ProductRow product={product} categories={categories} onSave={onSave} onDelete={vi.fn()} />,
+    );
+
+    await user.click(screen.getByLabelText(/edit sparkling water/i));
+    await user.clear(screen.getByLabelText(/name/i));
+    await user.type(screen.getByLabelText(/name/i), 'Still Water');
+    await user.click(screen.getByLabelText(/category/i));
+    await user.selectOptions(screen.getByLabelText(/category/i), 'Snacks');
+    await user.click(screen.getByLabelText(/save product/i));
+
+    expect(onSave).toHaveBeenCalledWith('prod-1', {
+      name: 'Still Water',
+      category: 'Snacks',
+      barcode: '123456',
+    });
+    expect(screen.queryByLabelText(/save product/i)).not.toBeInTheDocument();
+  });
+
+  it('surfaces validation errors from duplicate constraints', async () => {
+    const user = userEvent.setup();
+    const onSave = vi.fn().mockRejectedValueOnce(Object.assign(new Error('dup'), { name: 'DuplicateNameError' }))
+      .mockRejectedValueOnce(Object.assign(new Error('dup'), { name: 'DuplicateBarcodeError' }));
+
+    render(
+      <ProductRow product={product} categories={categories} onSave={onSave} onDelete={vi.fn()} />,
+    );
+
+    await user.click(screen.getByLabelText(/edit sparkling water/i));
+    await user.clear(screen.getByLabelText(/name/i));
+    await user.type(screen.getByLabelText(/name/i), 'Sparkling Water');
+    await user.click(screen.getByLabelText(/save product/i));
+
+    expect(await screen.findByText(/already exists/i)).toBeVisible();
+
+    await user.type(screen.getByLabelText(/barcode/i), '999');
+    await user.click(screen.getByLabelText(/save product/i));
+
+    expect(await screen.findByText(/already assigned/i)).toBeVisible();
+  });
+
+  it('allows clearing and scanning a new barcode', async () => {
+    const user = userEvent.setup();
+
+    render(
+      <ProductRow product={product} categories={categories} onSave={vi.fn()} onDelete={vi.fn()} />,
+    );
+
+    await user.click(screen.getByLabelText(/edit sparkling water/i));
+    await user.click(screen.getByRole('button', { name: /clear/i }));
+
+    expect(screen.getByRole('button', { name: /scan barcode/i })).toBeVisible();
+  });
 });