const expect = require('expect');
const xProd = require('./xProd.js');

test('xProd is a Function', () => {
  expect(xProd).toBeInstanceOf(Function);
});
test('xProd([1, 2], [\'a\', \'b\']) returns [[1, \'a\'], [1, \'b\'], [2, \'a\'], [2, \'b\']]', () => {
  expect(xProd([1, 2], ['a', 'b'])).toEqual([[1, 'a'], [1, 'b'], [2, 'a'], [2, 'b']]);
});