storybook/docs/snippets/web-components/storybook-test-fn-mock-spy.js.mdx

```ts
// NoteUI.stories.ts
import { expect, userEvent, within } from '@storybook/test';

import { saveNote } from '#app/actions.mock';
import { createNotes } from '#mocks/notes';

export default {
  title: 'Mocked/NoteUI',
  component: 'note-ui',
};

const notes = createNotes();

export const SaveFlow = {
  name: 'Save Flow ▶',
  args: {
    isEditing: true,
    note: notes[0],
  },
  play: async ({ canvasElement, step }) => {
    const canvas = within(canvasElement);

    const saveButton = canvas.getByRole('menuitem', { name: /done/i });
    await userEvent.click(saveButton);
    // 👇 This is the mock function, so you can assert its behavior
    await expect(saveNote).toHaveBeenCalled();
  },
};
```