bpo-42470: Do not warn on sequences which are also sets in random.sample() (GH-23665)
diff --git a/Lib/random.py b/Lib/random.py
index 139e8a4..66433ba 100644
--- a/Lib/random.py
+++ b/Lib/random.py
@@ -424,13 +424,14 @@ def sample(self, population, k, *, counts=None):
# too many calls to _randbelow(), making them slower and
# causing them to eat more entropy than necessary.
- if isinstance(population, _Set):
- _warn('Sampling from a set deprecated\n'
- 'since Python 3.9 and will be removed in a subsequent version.',
- DeprecationWarning, 2)
- population = tuple(population)
if not isinstance(population, _Sequence):
- raise TypeError("Population must be a sequence. For dicts or sets, use sorted(d).")
+ if isinstance(population, _Set):
+ _warn('Sampling from a set deprecated\n'
+ 'since Python 3.9 and will be removed in a subsequent version.',
+ DeprecationWarning, 2)
+ population = tuple(population)
+ else:
+ raise TypeError("Population must be a sequence. For dicts or sets, use sorted(d).")
n = len(population)
if counts is not None:
cum_counts = list(_accumulate(counts))
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index 0c1fdee..327bfa3 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -11,7 +11,7 @@
from math import log, exp, pi, fsum, sin, factorial
from test import support
from fractions import Fraction
-from collections import Counter
+from collections import abc, Counter
class TestBasicOps:
# Superclass with tests common to all generators.
@@ -163,6 +163,22 @@ def test_sample_on_sets(self):
population = {10, 20, 30, 40, 50, 60, 70}
self.gen.sample(population, k=5)
+ def test_sample_on_seqsets(self):
+ class SeqSet(abc.Sequence, abc.Set):
+ def __init__(self, items):
+ self._items = items
+
+ def __len__(self):
+ return len(self._items)
+
+ def __getitem__(self, index):
+ return self._items[index]
+
+ population = SeqSet([2, 4, 1, 3])
+ with warnings.catch_warnings():
+ warnings.simplefilter("error", DeprecationWarning)
+ self.gen.sample(population, k=2)
+
def test_sample_with_counts(self):
sample = self.gen.sample