def test_double_forwarding(self):
balances = Balances()
balances.add('a', 1)
balances.add('b', 2)
balances.add('c', 3)
balances.add('d', 4)
balances.add('e', 5)
balances.add('f', 6)
balances.addFirstRef('a')
balances.addFirstRef('b')
balances.consumeAndForward(['a', 'b', 'c'], 'e')
balances.consumeAndForward(['e'], 'f')
self.assertEqual(balances.getEndOfForwardingChainFrom('a'), 'f')
# can only forward from actual reference targets
self.assertRaises(AssertionError, balances.getEndOfForwardingChainFrom,
'e')
self.assertEqual(balances.getEndOfForwardingChainFrom('d'), 'd')
self.assertEqual(balances.changeCounts['a'], 0)
balances.removeRef('a')
self.assertFalse('a' in balances.changeCounts)
self.assertRaises(AssertionError, balances.getEndOfForwardingChainFrom,
'a')
self.assertEqual(balances.getEndOfForwardingChainFrom('b'), 'f')
self.assertTrue(balances.isReferenced('f'))
self.assertDictEqual(balances.changeCounts, {'b': 0})
balances.removeRef('b')
self.assertDictEqual(balances.changeCounts, {})
self.assertFalse('b' in balances.changeCounts)
self.assertRaises(AssertionError, balances.getEndOfForwardingChainFrom,
'b')
self.assertFalse(balances.isReferenced('f'))
self.assertDictEqual(balances.balances, {'d': 4, 'f': 17})
def test_single_forwarding(self):
balances = Balances()
self.assertRaises(AssertionError, balances.getEndOfForwardingChainFrom,
'a')
balances.add('a', 1)
balances.add('b', 2)
balances.add('c', 3)
balances.add('d', 4)
balances.add('e', 5)
balances.add('f', 6)
self.assertRaises(KeyError, balances.consumeAndForward,
['a', 'b', 'c'], 'g')
self.assertDictEqual(balances.balances, {
'a': 1,
'b': 2,
'c': 3,
'e': 5,
'd': 4,
'f': 6
})
self.assertEqual(balances.getEndOfForwardingChainFrom('a'), 'a')
balances.addFirstRef('a')
balances.addFirstRef('b')
balances.consumeAndForward(['a', 'b', 'c'], 'e')
self.assertEqual(balances.getEndOfForwardingChainFrom('a'), 'e')
self.assertRaises(AssertionError, balances.isReferenced, 'a')
self.assertEqual(balances.changeCounts['a'], 0)
self.assertEqual(balances.changeCounts['b'], 0)
self.assertTrue(balances.isReferenced('e'))
self.assertFalse(balances.isReferenced('f'))
# cannot start adding refs after a balance has been consumed
self.assertRaises(AssertionError, balances.addFirstRef, 'c')
balances.addRef('a')
balances.removeRef('a')
self.assertEqual(balances.changeCounts['a'], 0)
balances.removeRef('a')
self.assertFalse('a' in balances.changeCounts)
self.assertTrue(balances.isReferenced('e'))
self.assertDictEqual(balances.changeCounts, {'b': 0})
balances.removeRef('b')
self.assertFalse(balances.isReferenced('e'))
self.assertDictEqual(balances.balances, {'e': 11, 'd': 4, 'f': 6})
self.assertDictEqual(balances.changeCounts, {})