diff options
Diffstat (limited to 'Lib/test/test_iterlen.py')
| -rw-r--r-- | Lib/test/test_iterlen.py | 62 |
1 files changed, 29 insertions, 33 deletions
diff --git a/Lib/test/test_iterlen.py b/Lib/test/test_iterlen.py index 9101f6c884..152f5fc0cb 100644 --- a/Lib/test/test_iterlen.py +++ b/Lib/test/test_iterlen.py @@ -45,31 +45,21 @@ import unittest from test import support from itertools import repeat from collections import deque -from builtins import len as _len +from operator import length_hint n = 10 -def len(obj): - try: - return _len(obj) - except TypeError: - try: - # note: this is an internal undocumented API, - # don't rely on it in your own programs - return obj.__length_hint__() - except AttributeError: - raise TypeError class TestInvariantWithoutMutations: def test_invariant(self): it = self.it for i in reversed(range(1, n+1)): - self.assertEqual(len(it), i) + self.assertEqual(length_hint(it), i) next(it) - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) self.assertRaises(StopIteration, next, it) - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) class TestTemporarilyImmutable(TestInvariantWithoutMutations): @@ -78,12 +68,12 @@ class TestTemporarilyImmutable(TestInvariantWithoutMutations): # length immutability during iteration it = self.it - self.assertEqual(len(it), n) + self.assertEqual(length_hint(it), n) next(it) - self.assertEqual(len(it), n-1) + self.assertEqual(length_hint(it), n-1) self.mutate() self.assertRaises(RuntimeError, next, it) - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) ## ------- Concrete Type Tests ------- @@ -92,10 +82,6 @@ class TestRepeat(TestInvariantWithoutMutations, unittest.TestCase): def setUp(self): self.it = repeat(None, n) - def test_no_len_for_infinite_repeat(self): - # The repeat() object can also be infinite - self.assertRaises(TypeError, len, repeat(None)) - class TestXrange(TestInvariantWithoutMutations, unittest.TestCase): def setUp(self): @@ -167,14 +153,15 @@ class TestList(TestInvariantWithoutMutations, unittest.TestCase): it = iter(d) next(it) next(it) - self.assertEqual(len(it), n-2) + self.assertEqual(length_hint(it), n - 2) d.append(n) - self.assertEqual(len(it), n-1) # grow with append + self.assertEqual(length_hint(it), n - 1) # grow with append d[1:] = [] - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) self.assertEqual(list(it), []) d.extend(range(20)) - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) + class TestListReversed(TestInvariantWithoutMutations, unittest.TestCase): @@ -186,32 +173,41 @@ class TestListReversed(TestInvariantWithoutMutations, unittest.TestCase): it = reversed(d) next(it) next(it) - self.assertEqual(len(it), n-2) + self.assertEqual(length_hint(it), n - 2) d.append(n) - self.assertEqual(len(it), n-2) # ignore append + self.assertEqual(length_hint(it), n - 2) # ignore append d[1:] = [] - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) self.assertEqual(list(it), []) # confirm invariant d.extend(range(20)) - self.assertEqual(len(it), 0) + self.assertEqual(length_hint(it), 0) ## -- Check to make sure exceptions are not suppressed by __length_hint__() class BadLen(object): - def __iter__(self): return iter(range(10)) + def __iter__(self): + return iter(range(10)) + def __len__(self): raise RuntimeError('hello') + class BadLengthHint(object): - def __iter__(self): return iter(range(10)) + def __iter__(self): + return iter(range(10)) + def __length_hint__(self): raise RuntimeError('hello') + class NoneLengthHint(object): - def __iter__(self): return iter(range(10)) + def __iter__(self): + return iter(range(10)) + def __length_hint__(self): - return None + return NotImplemented + class TestLengthHintExceptions(unittest.TestCase): |