diff options
author | Steve Dower <steve.dower@microsoft.com> | 2017-02-04 14:55:16 -0800 |
---|---|---|
committer | Steve Dower <steve.dower@microsoft.com> | 2017-02-04 14:55:16 -0800 |
commit | b53654b6dbfce8318a7d4d1cdaddca7a7fec194b (patch) | |
tree | 204df61b2fb23424603db767732db35a687529c6 /Lib/test/test_set.py | |
parent | e1ac7d87afad9c07ec25e5705bb135b71347b581 (diff) | |
parent | 2296b978597ce62ec2185b78a43811610af2c0ea (diff) | |
download | cpython-b53654b6dbfce8318a7d4d1cdaddca7a7fec194b.tar.gz |
Issue #29416: Prevent infinite loop in pathlib.Path.mkdir
Diffstat (limited to 'Lib/test/test_set.py')
-rw-r--r-- | Lib/test/test_set.py | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/Lib/test/test_set.py b/Lib/test/test_set.py index 7594303132..0202981d67 100644 --- a/Lib/test/test_set.py +++ b/Lib/test/test_set.py @@ -6,10 +6,11 @@ import operator import copy import pickle from random import randrange, shuffle -import sys import warnings import collections import collections.abc +import itertools +import string class PassThru(Exception): pass @@ -729,6 +730,25 @@ class TestFrozenSet(TestJointOps, unittest.TestCase): addhashvalue(hash(frozenset([e for e, m in elemmasks if m&i]))) self.assertEqual(len(hashvalues), 2**n) + def zf_range(n): + # https://en.wikipedia.org/wiki/Set-theoretic_definition_of_natural_numbers + nums = [frozenset()] + for i in range(n-1): + num = frozenset(nums) + nums.append(num) + return nums[:n] + + def powerset(s): + for i in range(len(s)+1): + yield from map(frozenset, itertools.combinations(s, i)) + + for n in range(18): + t = 2 ** n + mask = t - 1 + for nums in (range, zf_range): + u = len({h & mask for h in map(hash, powerset(nums(n)))}) + self.assertGreater(4*u, t) + class FrozenSetSubclass(frozenset): pass |