(Medium) When Code Duplication In Tests Is Acceptable - Cart Test Example

CartTestExample.js

module('Shirts cart');

test('a valid product can be retrieved from the cart after being added', () => {
  const fakeShirt = Product()
    .asType('shirt') // Mandatory
    .withSize('XL') // Mandatory
    .withColor('black'); // Mandatory
  const cart = ShirtsCart();
  cart.addProduct(fakeShirt);
  expect(cart).toContain(fakeShirt);
});

test('when we try to add an invalid product to the cart then it\'s not added', () => {
  const fakePants = Product()
    .asType('pants') // Mandatory
    .withSize('XL') // Mandatory
    .withColor('black'); // Mandatory
  const cart = ShirtsCart();
  cart.addProduct(fakePants);
  expect(cart).not.toContain(fakePants);
});