Issue #18844: Add more tests
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index 840f3e7..4d5a874 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -205,6 +205,20 @@
]:
self.assertTrue(set(choices(data, cum_weights=weights, k=5)) <= set(data))
+ # Test weight focused on a single element of the population
+ self.assertEqual(choices('abcd', [1, 0, 0, 0]), ['a'])
+ self.assertEqual(choices('abcd', [0, 1, 0, 0]), ['b'])
+ self.assertEqual(choices('abcd', [0, 0, 1, 0]), ['c'])
+ self.assertEqual(choices('abcd', [0, 0, 0, 1]), ['d'])
+
+ # Test consistency with random.choice() for empty population
+ with self.assertRaises(IndexError):
+ choices([], k=1)
+ with self.assertRaises(IndexError):
+ choices([], weights=[], k=1)
+ with self.assertRaises(IndexError):
+ choices([], cum_weights=[], k=5)
+
def test_gauss(self):
# Ensure that the seed() method initializes all the hidden state. In
# particular, through 2.2.1 it failed to reset a piece of state used