bpo-36907: fix refcount bug in _PyStack_UnpackDict() (GH-13381)
diff --git a/Lib/test/test_call.py b/Lib/test/test_call.py
index 0da0719..e4ab33c 100644
--- a/Lib/test/test_call.py
+++ b/Lib/test/test_call.py
@@ -8,6 +8,7 @@
import struct
import collections
import itertools
+import gc
class FunctionCalls(unittest.TestCase):
@@ -457,6 +458,22 @@
result = _testcapi.pyobject_fastcallkeywords(func, args, kwnames)
self.check_result(result, expected)
+ def test_fastcall_clearing_dict(self):
+ # Test bpo-36907: the point of the test is just checking that this
+ # does not crash.
+ class IntWithDict:
+ __slots__ = ["kwargs"]
+ def __init__(self, **kwargs):
+ self.kwargs = kwargs
+ def __index__(self):
+ self.kwargs.clear()
+ gc.collect()
+ return 0
+ x = IntWithDict(dont_inherit=IntWithDict())
+ # We test the argument handling of "compile" here, the compilation
+ # itself is not relevant. When we pass flags=x below, x.__index__() is
+ # called, which changes the keywords dict.
+ compile("pass", "", "exec", x, **x.kwargs)
if __name__ == "__main__":
unittest.main()