diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/decimal.py | 6 | ||||
| -rw-r--r-- | Lib/test/seq_tests.py | 3 | ||||
| -rw-r--r-- | Lib/test/test_descr.py | 8 | ||||
| -rw-r--r-- | Lib/test/test_hash.py | 70 | ||||
| -rw-r--r-- | Lib/test/test_richcmp.py | 64 |
5 files changed, 82 insertions, 69 deletions
diff --git a/Lib/decimal.py b/Lib/decimal.py index 180b177..2c02f11 100644 --- a/Lib/decimal.py +++ b/Lib/decimal.py @@ -3783,10 +3783,8 @@ class Context(object): for flag in flags: self._ignored_flags.remove(flag) - def __hash__(self): - """A Context cannot be hashed.""" - # We inherit object.__hash__, so we must deny this explicitly - raise TypeError("Cannot hash a Context.") + # We inherit object.__hash__, so we must deny this explicitly + __hash__ = None def Etiny(self): """Returns Etiny (= Emin - prec + 1)""" diff --git a/Lib/test/seq_tests.py b/Lib/test/seq_tests.py index dd12ee3..962cfe1 100644 --- a/Lib/test/seq_tests.py +++ b/Lib/test/seq_tests.py @@ -212,8 +212,7 @@ class CommonTest(unittest.TestCase): # So instances of AllEq must be found in all non-empty sequences. def __eq__(self, other): return True - def __hash__(self): - raise NotImplemented + __hash__ = None # Can't meet hash invariant requirements self.assert_(AllEq() not in self.type2test([])) self.assert_(AllEq() in self.type2test([1])) diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py index bfbb400..3c0bae0 100644 --- a/Lib/test/test_descr.py +++ b/Lib/test/test_descr.py @@ -3070,12 +3070,20 @@ order (MRO) for bases """ self.assertEqual(hash(d), 144) D.__hash__ = lambda self: 100 self.assertEqual(hash(d), 100) + D.__hash__ = None + self.assertRaises(TypeError, hash, d) del D.__hash__ self.assertEqual(hash(d), 144) + B.__hash__ = None + self.assertRaises(TypeError, hash, d) del B.__hash__ self.assertEqual(hash(d), 314) + C.__hash__ = None + self.assertRaises(TypeError, hash, d) del C.__hash__ self.assertEqual(hash(d), 42) + A.__hash__ = None + self.assertRaises(TypeError, hash, d) del A.__hash__ self.assertEqual(hash(d), orig_hash) d.foo = 42 diff --git a/Lib/test/test_hash.py b/Lib/test/test_hash.py index fb1699a..56974b8 100644 --- a/Lib/test/test_hash.py +++ b/Lib/test/test_hash.py @@ -1,9 +1,11 @@ # test the invariant that # iff a==b then hash(a)==hash(b) # +# Also test that hash implementations are inherited as expected import unittest from test import support +from collections import Hashable class HashEqualityTestCase(unittest.TestCase): @@ -37,8 +39,74 @@ class HashEqualityTestCase(unittest.TestCase): self.same_hash(float(0.5), complex(0.5, 0.0)) +_default_hash = object.__hash__ +class DefaultHash(object): pass + +_FIXED_HASH_VALUE = 42 +class FixedHash(object): + def __hash__(self): + return _FIXED_HASH_VALUE + +class OnlyEquality(object): + def __eq__(self, other): + return self is other + +class OnlyInequality(object): + def __ne__(self, other): + return self is not other + +class OnlyCmp(object): + def __cmp__(self, other): + return cmp(id(self), id(other)) + +class InheritedHashWithEquality(FixedHash, OnlyEquality): pass +class InheritedHashWithInequality(FixedHash, OnlyInequality): pass +class InheritedHashWithCmp(FixedHash, OnlyCmp): pass + +class NoHash(object): + __hash__ = None + +class HashInheritanceTestCase(unittest.TestCase): + default_expected = [object(), + DefaultHash(), + OnlyInequality(), + ] + fixed_expected = [FixedHash(), + InheritedHashWithEquality(), + InheritedHashWithInequality(), + InheritedHashWithCmp(), + ] + error_expected = [NoHash(), + OnlyEquality(), + OnlyCmp(), + ] + + def test_default_hash(self): + for obj in self.default_expected: + self.assertEqual(hash(obj), _default_hash(obj)) + + def test_fixed_hash(self): + for obj in self.fixed_expected: + self.assertEqual(hash(obj), _FIXED_HASH_VALUE) + + def test_error_hash(self): + for obj in self.error_expected: + self.assertRaises(TypeError, hash, obj) + + def test_hashable(self): + objects = (self.default_expected + + self.fixed_expected) + for obj in objects: + self.assert_(isinstance(obj, Hashable), repr(obj)) + + def test_not_hashable(self): + for obj in self.error_expected: + self.assertFalse(isinstance(obj, Hashable), repr(obj)) + + def test_main(): - support.run_unittest(HashEqualityTestCase) + support.run_unittest(HashEqualityTestCase, + HashInheritanceTestCase) if __name__ == "__main__": diff --git a/Lib/test/test_richcmp.py b/Lib/test/test_richcmp.py index 30dac8f..435de75 100644 --- a/Lib/test/test_richcmp.py +++ b/Lib/test/test_richcmp.py @@ -48,8 +48,7 @@ class Vector: def __setitem__(self, i, v): self.data[i] = v - def __hash__(self): - raise TypeError("Vectors cannot be hashed") + __hash__ = None # Vectors cannot be hashed def __bool__(self): raise TypeError("Vectors cannot be used in Boolean contexts") @@ -85,35 +84,6 @@ class Vector: raise ValueError("Cannot compare vectors of different length") return other - -class SimpleOrder(object): - """ - A simple class that defines order but not full comparison. - """ - - def __init__(self, value): - self.value = value - - def __lt__(self, other): - if not isinstance(other, SimpleOrder): - return True - return self.value < other.value - - def __gt__(self, other): - if not isinstance(other, SimpleOrder): - return False - return self.value > other.value - - -class DumbEqualityWithoutHash(object): - """ - A class that define __eq__, but no __hash__: it shouldn't be hashable. - """ - - def __eq__(self, other): - return False - - opmap = { "lt": (lambda a,b: a< b, operator.lt, operator.__lt__), "le": (lambda a,b: a<=b, operator.le, operator.__le__), @@ -360,38 +330,8 @@ class ListTest(unittest.TestCase): self.assertIs(op(x, y), True) -class HashableTest(unittest.TestCase): - """ - Test hashability of classes with rich operators defined. - """ - - def test_simpleOrderHashable(self): - """ - A class that only defines __gt__ and/or __lt__ should be hashable. - """ - a = SimpleOrder(1) - b = SimpleOrder(2) - self.assert_(a < b) - self.assert_(b > a) - self.assert_(a.__hash__ is not None) - - def test_notHashableException(self): - """ - If a class is not hashable, it should raise a TypeError with an - understandable message. - """ - a = DumbEqualityWithoutHash() - try: - hash(a) - except TypeError as e: - self.assertEquals(str(e), - "unhashable type: 'DumbEqualityWithoutHash'") - else: - raise support.TestFailed("Should not be here") - - def test_main(): - support.run_unittest(VectorTest, NumberTest, MiscTest, DictTest, ListTest, HashableTest) + support.run_unittest(VectorTest, NumberTest, MiscTest, DictTest, ListTest) if __name__ == "__main__": test_main() |