bpo-29960 _random.Random corrupted on exception in setstate(). (#1019)
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index 78909dd..48077fb 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -423,6 +423,7 @@
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
@@ -436,6 +437,10 @@
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
diff --git a/Misc/ACKS b/Misc/ACKS
index d4f20c5..ab41431 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1110,6 +1110,7 @@
Pascal Oberndoerfer
Jeffrey Ollie
Adam Olsen
+Bryan Olson
Grant Olson
Koray Oner
Piet van Oostrum
diff --git a/Misc/NEWS b/Misc/NEWS
index fe1b0f8..72fcded 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -317,6 +317,9 @@
Library
-------
+- bpo-29960: Preserve generator state when _random.Random.setstate()
+ raises an exception. Patch by Bryan Olson.
+
- bpo-29802: Fixed reference counting in module-level struct functions when
pass arguments of wrong type.
diff --git a/Modules/_randommodule.c b/Modules/_randommodule.c
index 6db1d2d..9953654 100644
--- a/Modules/_randommodule.c
+++ b/Modules/_randommodule.c
@@ -348,6 +348,7 @@
int i;
unsigned long element;
long index;
+ uint32_t new_state[N];
if (!PyTuple_Check(state)) {
PyErr_SetString(PyExc_TypeError,
@@ -364,7 +365,7 @@
element = PyLong_AsUnsignedLong(PyTuple_GET_ITEM(state, i));
if (element == (unsigned long)-1 && PyErr_Occurred())
return NULL;
- self->state[i] = (uint32_t)element;
+ new_state[i] = (uint32_t)element;
}
index = PyLong_AsLong(PyTuple_GET_ITEM(state, i));
@@ -375,6 +376,8 @@
return NULL;
}
self->index = (int)index;
+ for (i = 0; i < N; i++)
+ self->state[i] = new_state[i];
Py_RETURN_NONE;
}