[3.6] bpo-29960 _random.Random corrupted on exception in setstate(). … (#1287)
(cherry picked from commit 9616a82e7802241a4b74cf7ae38d43c37bf66e48)
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index 5b6a4f0..03adc0a 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -427,6 +427,7 @@
self.assertRaises(ValueError, self.gen.setstate, (1, None, None))
def test_setstate_middle_arg(self):
+ start_state = self.gen.getstate()
# Wrong type, s/b tuple
self.assertRaises(TypeError, self.gen.setstate, (2, None, None))
# Wrong length, s/b 625
@@ -440,6 +441,10 @@
self.gen.setstate((2, (1,)*624+(625,), None))
with self.assertRaises((ValueError, OverflowError)):
self.gen.setstate((2, (1,)*624+(-1,), None))
+ # Failed calls to setstate() should not have changed the state.
+ bits100 = self.gen.getrandbits(100)
+ self.gen.setstate(start_state)
+ self.assertEqual(self.gen.getrandbits(100), bits100)
# Little trick to make "tuple(x % (2**32) for x in internalstate)"
# raise ValueError. I cannot think of a simple way to achieve this, so