Expand unit test coverage

modified:   maintenance.sh
	modified:   package-lock.json
	modified:   package.json
	new file:   src/screens/ActivePickListScreen.more.test.tsx
	new file:   src/screens/ManageCategoriesScreen.additional.test.tsx
	new file:   src/testUtils/mockDb.test.ts

src/screens/ManageCategoriesScreen.additional.test.tsx

@@ -0,0 +1,122 @@
+// src/screens/ManageCategoriesScreen.additional.test.tsx
+import { MemoryRouter } from 'react-router-dom';
+import { render, screen, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import ManageCategoriesScreen from './ManageCategoriesScreen';
+
+const categories = [
+  { id: 'cat-1', name: 'Snacks', created_at: 0, updated_at: 0 },
+  { id: 'cat-2', name: 'Drinks', created_at: 0, updated_at: 0 },
+];
+
+const products = [
+  { id: 'prod-1', name: 'Chips', category: 'Snacks', archived: false, created_at: 0, updated_at: 0 },
+];
+
+const categoryAddMock = vi.fn();
+const categoryUpdateMock = vi.fn();
+const categoryDeleteMock = vi.fn();
+const productModifyMock = vi.fn();
+const pickListsUpdateMock = vi.fn();
+
+// Mock hooks
+vi.mock('../hooks/dataHooks', () => ({
+  useCategories: () => categories,
+  useProducts: () => products,
+}));
+
+// Mock DBProvider to catch pickLists.update and categories.update/delete
+vi.mock('../context/DBProvider', () => ({
+  useDatabase: () => ({
+    transaction: async (...args: unknown[]) => {
+      const cb = args[args.length - 1];
+      if (typeof cb === 'function') await (cb as () => Promise<void>)();
+    },
+    categories: { add: categoryAddMock, update: categoryUpdateMock, delete: categoryDeleteMock },
+    products: {
+      where: () => ({
+        equals: (_: string) => ({
+          count: async () => 0,
+          modify: async (changes: any) => productModifyMock(changes),
+        }),
+      }),
+    },
+    pickLists: {
+      toArray: async () => [{ id: 'pl-1', categories: ['Snacks'], created_at: 0, updated_at: 0 }],
+      update: pickListsUpdateMock,
+    },
+  }),
+}));
+
+describe('ManageCategoriesScreen additional', () => {
+  beforeEach(() => {
+    categoryAddMock.mockReset();
+    categoryUpdateMock.mockReset();
+    categoryDeleteMock.mockReset();
+    productModifyMock.mockReset();
+    pickListsUpdateMock.mockReset();
+  });
+
+  it('updates pickLists when category name is changed (legacy name in pickLists.categories)', async () => {
+    const user = userEvent.setup();
+    render(
+      <MemoryRouter>
+        <ManageCategoriesScreen />
+      </MemoryRouter>,
+    );
+
+    await user.click(screen.getByRole('button', { name: /edit snacks/i }));
+    const editField = screen.getByDisplayValue(/snacks/i);
+    await user.clear(editField);
+    await user.type(editField, 'Treats');
+    await user.click(screen.getByRole('button', { name: /save category/i }));
+
+    // categories.update should have been called
+    expect(categoryUpdateMock).toHaveBeenCalled();
+
+    // and pickLists.update should have been called to update the categories array
+    expect(pickListsUpdateMock).toHaveBeenCalled();
+    expect(await screen.findByText(/category updated/i)).toBeVisible();
+  });
+
+  it('deletes category when no products reference it', async () => {
+    // products.where().equals().count() is 0 in our mock, so delete should proceed
+    const user = userEvent.setup();
+    render(
+      <MemoryRouter>
+        <ManageCategoriesScreen />
+      </MemoryRouter>,
+    );
+
+    // Click the "Delete Snacks" icon/button (specific aria-label)
+    await user.click(screen.getByRole('button', { name: /delete snacks/i }));
+
+    // Wait for the delete mock to be called (component calls the onDelete handler)
+    await waitFor(() => {
+      expect(categoryDeleteMock).toHaveBeenCalled();
+    });
+
+    // And assert the success alert is shown
+    expect(await screen.findByText(/category deleted/i)).toBeVisible();
+  });
+
+  it('prevents renaming to an existing name', async () => {
+    const user = userEvent.setup();
+    render(
+      <MemoryRouter>
+        <ManageCategoriesScreen />
+      </MemoryRouter>,
+    );
+
+    await user.click(screen.getByRole('button', { name: /edit snacks/i }));
+    const editField = screen.getByDisplayValue(/snacks/i);
+    await user.clear(editField);
+    await user.type(editField, 'Drinks'); // name that already exists
+    await user.click(screen.getByRole('button', { name: /save category/i }));
+
+    // Should show "already exists" and NOT call update
+    expect(categoryUpdateMock).not.toHaveBeenCalled();
+    expect(await screen.findByText(/already exists/i)).toBeVisible();
+  });
+});