def setUp(self):
self.res = ExponentiallyDecayingReservoir(15)
class TestExponentiallyDecayingReservoir(TestCase):
def setUp(self):
self.res = ExponentiallyDecayingReservoir(15)
def test_sample_weight(self):
for dt, w in [(0, 1),
(1800, 532048240601.79865),
(3600, 2.830753303274694e+23)]:
self.assertEqual(w, self.res._sample_weight(dt))
@patch('caliper.reservoir.datetime')
def test_set_next_rescale(self, datetime_mock):
now = datetime.now()
datetime_mock.now.return_value = now
self.res._set_next_rescale()
self.assertEqual(now + timedelta(hours=1), self.res._next_rescale)
def test_add_15_elements(self):
for i in range(15):
self.res.update(i)
self.assertEqual(len(self.res), 15)
def test_add_30_elements(self):
for i in range(30):
self.res.update(i)
self.assertEqual(len(self.res), 30)
self.assertEqual(len(self.res._res), 15)
def test_add_to_full_reservoir(self):
self.res._res = dict((i, (i, i)) for i in range(15))
self.res._landmark = datetime.now() - timedelta(minutes=30)
self.res._count = 15
self.assertTrue(0 in self.res._res)
# Python 2.6 only supports nested CMs through contextlib.nested,
# which is deprecated in 3.x. Easiest solution is to make this
# indent-hell. A better solution would be to split the tests up
# into multiple cases that each test one assertion.
with patch.object(self.res, '_rescale_if_needed') as _rin:
with patch.object(self.res, '_rescale') as _rescale:
with patch.object(self.res, '_sample_weight') as _sample_weight:
with patch('caliper.reservoir.random') as random:
random.return_value = 0.5
_sample_weight.return_value = 20
self.res.update(42)
_rin.assert_called_once_with()
_rescale.assert_not_called()
random.assert_called_once_with()
for k, (v, w) in self.res._res.items():
if v == 42:
self.assertEqual(w, 20)
self.assertEqual(k, 40)
break
else:
self.assertTrue(False)
self.assertEqual(len(self.res._res), 15)
self.assertFalse(0 in self.res._res)
def test_rescale(self):
now = datetime.now()
landmark = now - timedelta(seconds=3600)
self.res._landmark = landmark
self.res._res = dict((i, (i, 2 * i)) for i in range(15))
self.res._count = 15
# Python 2.6 only supports nested CMs through contextlib.nested,
# which is deprecated in 3.x. Easiest solution is to make this
# indent-hell. A better solution would be to split the tests up
# into multiple cases that each test one assertion.
with patch.object(self.res, '_set_next_rescale') as _set_next_resacle:
with patch('caliper.reservoir.exp') as exp:
with patch('caliper.reservoir.datetime') as datetime_mock:
datetime_mock.now.return_value = now
exp.return_value = 0.5
self.res._rescale()
datetime_mock.now.assert_called_once_with()
exp.assert_called_once_with(-0.015 * 3600)
_set_next_resacle.assert_called_once_with()
expected = dict((0.5 * i, (i, i)) for i in range(15))
self.assertEqual(self.res._res, expected)