def test_articles(self):
order = self.create_content('collective.cart.core.Order', id='1')
adapter = IOrderAdapter(order)
self.assertEqual(len(adapter.articles()), 0)
self.create_content('collective.cart.core.OrderArticle', order, id='1')
self.create_content('collective.cart.core.OrderArticle', order, id='2')
self.assertEqual(len(adapter.articles()), 2)
