def testMaxResults(self):
"""Ensure the maxResults argument is respected."""
maxResults = 12
bi = simpleBackoffIterator(now=False, maxResults=maxResults)
for _ in range(maxResults):
bi.next()
self.assertRaises(StopIteration, bi.next)
def testInitDelay(self):
"""If an initial delay is passed, it must be the first value
returned by the iterator."""
initDelay = 7
bi = simpleBackoffIterator(now=False, initDelay=initDelay)
delay = bi.next()
self.assertEqual(initDelay, delay)
def testNowDefault(self):
"""When now is not specified, the first delay the iterator returns
must be zero (in other words we're testing that by default the
function will be called immediately)."""
bi = simpleBackoffIterator()
delay = bi.next()
self.assertEqual(0.0, delay)
def testAdd3(self):
"""Make a back-off iterator whose increment function adds 3 to the
previous delay and check its results."""
bi = simpleBackoffIterator(now=False,
initDelay=2.0,
incFunc=partial(add, 3.0),
maxDelay=10.0,
maxResults=10)
self.assertEqual(2.0, bi.next())
self.assertEqual(5.0, bi.next())
self.assertEqual(8.0, bi.next())
def testMul3(self):
"""Make a back-off iterator whose increment function multiplies the
previous delay by 3 and check its results."""
bi = simpleBackoffIterator(now=False,
initDelay=1.0,
incFunc=partial(mul, 3.0),
maxDelay=10.0,
maxResults=10)
self.assertEqual(1.0, bi.next())
self.assertEqual(3.0, bi.next())
self.assertEqual(9.0, bi.next())
def testConstant(self):
"""Make a back-off iterator that yields a constant for a certain
number of times, and check its results."""
n = 10
constant = 5.0
initDelay = 3.0
bi = simpleBackoffIterator(now=False,
initDelay=initDelay,
incFunc=lambda _: constant,
maxDelay=10.0,
maxResults=n + 1)
self.assertEqual(initDelay, bi.next())
for _ in range(n):
self.assertEqual(constant, bi.next())
def testMaxDelay(self):
"""Make a back-off iterator whose increment function multiplies the
previous delay by 3 and check that it returns the passed maxDelay
value once the delay would be too large."""
bi = simpleBackoffIterator(now=False,
initDelay=1.0,
incFunc=partial(mul, 3.0),
maxDelay=10.0,
maxResults=10)
self.assertEqual(1.0, bi.next())
self.assertEqual(3.0, bi.next())
self.assertEqual(9.0, bi.next())
self.assertEqual(10.0, bi.next())
self.assertEqual(10.0, bi.next())
def testDefaultSettingsNoNegativeDelays(self):
"""Ensure no negative values are yielded by the iterator."""
bi = simpleBackoffIterator()
for delay in bi:
self.assertTrue(delay >= 0.0)
def exhaust():
"""Set up a default iterator and keep call its next method
forever. If it doesn't raise this test will never finish."""
bi = simpleBackoffIterator()
while True:
bi.next()
def testNotNow(self):
"""When now=False is passed to the back-off iterator, the first
delay it returns must not be zero."""
bi = simpleBackoffIterator(now=False)
delay = bi.next()
self.assertNotEqual(0.0, delay)
def testNow(self):
"""When now=True is passed to the back-off iterator, the first
delay it returns must be zero."""
bi = simpleBackoffIterator(now=True)
delay = six.next(bi)
self.assertEqual(0.0, delay)