old_contents: import unittest2
  
  from ..purchase_group_hooks import PurchaseOrder
  
  
  class TestGroupOrders(unittest2.TestCase):
  
      def setUp(self):
          super(TestGroupOrders, self).setUp()
  
      def test_no_orders(self):
          """Group an empty list of orders as an empty dictionary."""
  
          grouped = PurchaseOrder._group_orders([])
          self.assertEquals(grouped, {})
  
new_contents: import unittest2
  from mock import Mock
  
  from ..purchase_group_hooks import PurchaseOrder
  
  
  class TestGroupOrders(unittest2.TestCase):
  
      def setUp(self):
          super(TestGroupOrders, self).setUp()
          self.order1 = Mock()
          self.order2 = Mock()
  
      def test_no_orders(self):
          """Group an empty list of orders as an empty dictionary."""
  
          grouped = PurchaseOrder._group_orders([])
          self.assertEquals(grouped, {})
  
      def test_one_order(self):
          """A single order will not be grouped."""
          grouped = PurchaseOrder._group_orders([self.order1])
          self.assertEquals(grouped, {})
  
subject: test merging one order