bluechips/tests/lib/test_totals.py

   1 from unittest import TestCase
   2 from bluechips.lib import totals
   3
   4 class TestReorderingSettle(TestCase):
   5     def test_transfer_minimized(self):
   6         """
   7         Test that the number of transfers is actually minimized.
   8
   9         Taken from a real-world situation, we discovered that failing
  10         to re-order the debt lists after every transfer could lead to
  11         extra, unnecessary transfers.
  12         """
  13         self.assertEqual(len(totals.settle({'Alice': 100,
  14                                             'Bob': -85,
  15                                             'Charlie': 35,
  16                                             'Dave': -35,
  17                                             'Eve': -15})),
  18                          3)
  19
  20     def test_settle_even(self):
  21         transfers = totals.settle({'Alice': 0,
  22                                    'Bob': 0,
  23                                    'Charlie': 0})
  24         assert transfers == []
  25
  26     def test_settle_positive(self):
  27         transfers = totals.settle({'Alice': -50,
  28                                    'Bob': 100,
  29                                    'Charlie': -50})
  30         assert transfers == [('Bob', 'Charlie', 50),
  31                              ('Bob', 'Alice', 50)]
  32
  33     def test_settle_uneven_positive(self):
  34         try:
  35             transfers = totals.settle({'Alice': -50,
  36                                        'Bob': -50,
  37                                        'Charlie': -50})
  38         except totals.DirtyBooks:
  39             pass
  40
  41     def test_settle_uneven_negative(self):
  42         try:
  43             transfers = totals.settle({'Alice': 50,
  44                                        'Bob': 50,
  45                                        'Charlie': 50})
  46         except totals.DirtyBooks:
  47             pass