diff --git a/Lib/_collections_abc.py b/Lib/_collections_abc.py index d92b848e943..bff58ad4a7f 100644 --- a/Lib/_collections_abc.py +++ b/Lib/_collections_abc.py @@ -696,6 +696,7 @@ class Set(Collection): hx = hash(x) h ^= (hx ^ (hx << 16) ^ 89869747) * 3644798167 h &= MASK + h ^= (h >> 11) ^ (h >> 25) h = h * 69069 + 907133923 h &= MASK if h > MAX: diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py index f98048b34a7..1f659d7d604 100644 --- a/Lib/test/test_collections.py +++ b/Lib/test/test_collections.py @@ -1801,6 +1801,18 @@ class TestCollectionABCs(ABCTestCase): self.assertTrue(f1 != l1) self.assertTrue(f1 != l2) + def test_Set_hash_matches_frozenset(self): + sets = [ + {}, {1}, {None}, {-1}, {0.0}, {"abc"}, {1, 2, 3}, + {10**100, 10**101}, {"a", "b", "ab", ""}, {False, True}, + {object(), object(), object()}, {float("nan")}, {frozenset()}, + {*range(1000)}, {*range(1000)} - {100, 200, 300}, + {*range(sys.maxsize - 10, sys.maxsize + 10)}, + ] + for s in sets: + fs = frozenset(s) + self.assertEqual(hash(fs), Set._hash(fs), msg=s) + def test_Mapping(self): for sample in [dict]: self.assertIsInstance(sample(), Mapping) diff --git a/Misc/NEWS.d/next/Library/2021-07-21-23-16-30.bpo-44704.iqHLxQ.rst b/Misc/NEWS.d/next/Library/2021-07-21-23-16-30.bpo-44704.iqHLxQ.rst new file mode 100644 index 00000000000..586661876de --- /dev/null +++ b/Misc/NEWS.d/next/Library/2021-07-21-23-16-30.bpo-44704.iqHLxQ.rst @@ -0,0 +1 @@ +The implementation of ``collections.abc.Set._hash()`` now matches that of ``frozenset.__hash__()``. \ No newline at end of file