bpo-35409: Ignore GeneratorExit in async_gen_athrow_throw (GH-14755)

Ignore `GeneratorExit` exceptions when throwing an exception into the `aclose` coroutine of an asynchronous generator.

https://bugs.python.org/issue35409
(cherry picked from commit 8e0de2a4808d7c2f4adedabff89ee64e0338790a)

Co-authored-by: Vincent Michel <vxgmichel@gmail.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/Objects/genobject.c b/Objects/genobject.c
index 6285219..5643553 100644
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -1947,6 +1947,17 @@ async_gen_athrow_throw(PyAsyncGenAThrow *o, PyObject *args)
             PyErr_SetString(PyExc_RuntimeError, ASYNC_GEN_IGNORED_EXIT_MSG);
             return NULL;
         }
+        if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration) ||
+            PyErr_ExceptionMatches(PyExc_GeneratorExit))
+        {
+            /* when aclose() is called we don't want to propagate
+               StopAsyncIteration or GeneratorExit; just raise
+               StopIteration, signalling that this 'aclose()' await
+               is done.
+            */
+            PyErr_Clear();
+            PyErr_SetNone(PyExc_StopIteration);
+        }
         return retval;
     }
 }