diff options
Diffstat (limited to 'Lib/test/test_operator.py')
| -rw-r--r-- | Lib/test/test_operator.py | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/Lib/test/test_operator.py b/Lib/test/test_operator.py index fa608b9a52..b445ee0ada 100644 --- a/Lib/test/test_operator.py +++ b/Lib/test/test_operator.py @@ -410,6 +410,31 @@ class OperatorTestCase(unittest.TestCase): self.assertEqual(operator.__ixor__ (c, 5), "ixor") self.assertEqual(operator.__iconcat__ (c, c), "iadd") + def test_length_hint(self): + class X(object): + def __init__(self, value): + self.value = value + + def __length_hint__(self): + if type(self.value) is type: + raise self.value + else: + return self.value + + self.assertEqual(operator.length_hint([], 2), 0) + self.assertEqual(operator.length_hint(iter([1, 2, 3])), 3) + + self.assertEqual(operator.length_hint(X(2)), 2) + self.assertEqual(operator.length_hint(X(NotImplemented), 4), 4) + self.assertEqual(operator.length_hint(X(TypeError), 12), 12) + with self.assertRaises(TypeError): + operator.length_hint(X("abc")) + with self.assertRaises(ValueError): + operator.length_hint(X(-2)) + with self.assertRaises(LookupError): + operator.length_hint(X(LookupError)) + + def test_main(verbose=None): import sys test_classes = ( |