def test_clean_articles_in_cart(self, clean_articles_in_cart, IStock):
article1 = self.create_content('collective.cart.core.Article')
uuid1 = IUUID(article1)
article2 = self.create_content('collective.cart.core.Article')
uuid2 = IUUID(article2)
clean_articles_in_cart.return_value = {uuid1: {}, uuid2: {}}
IStock().stock = 0
instance = IShoppingSite(self.portal)
instance.update_cart = mock.Mock()
self.assertEqual(instance.clean_articles_in_cart(), {})
instance.update_cart.assert_called_with('articles', {})
