Small optimization for corner case where maxlen==0.

This commit is contained in:
Raymond Hettinger 2009-03-10 09:36:07 +00:00
parent 2cf03a8204
commit 060c7f6bba
2 changed files with 41 additions and 1 deletions

View file

@ -51,7 +51,9 @@ class TestBasic(unittest.TestCase):
def test_maxlen(self):
self.assertRaises(ValueError, deque, 'abc', -1)
self.assertRaises(ValueError, deque, 'abc', -2)
d = deque(range(10), maxlen=3)
it = iter(range(10))
d = deque(it, maxlen=3)
self.assertEqual(list(it), [])
self.assertEqual(repr(d), 'deque([7, 8, 9], maxlen=3)')
self.assertEqual(list(d), [7, 8, 9])
self.assertEqual(d, deque(range(10), 3))
@ -88,6 +90,21 @@ class TestBasic(unittest.TestCase):
fo.close()
support.unlink(support.TESTFN)
def test_maxlen_zero(self):
it = iter(range(100))
deque(it, maxlen=0)
self.assertEqual(list(it), [])
it = iter(range(100))
d = deque(maxlen=0)
d.extend(it)
self.assertEqual(list(it), [])
it = iter(range(100))
d = deque(maxlen=0)
d.extendleft(it)
self.assertEqual(list(it), [])
def test_comparisons(self):
d = deque('xabc'); d.popleft()
for e in [d, deque('abc'), deque('ab'), deque(), list(d)]: