// basic.tsx

import util from 'node:util';
import child_process from 'node:child_process';

const myFunction = () => {
  const exec = util.promisify(child_process.exec);
  return exec('echo "hi"');
};

export default myFunction;



// basic.test.tsx

import { expect, test, vi } from 'vitest';
import child_process from 'node:child_process';
import myFunction from './basic';

test('exec does the right thing', async () => {
  const execSpy = vi
    .spyOn(child_process, 'exec')
    .mockImplementation((_, callback) => {
      callback(null, 'success!');
    });

  await myFunction();

  expect(execSpy).toHaveBeenCalledWith('echo "hi"', expect.any(Function));
});