[3.12] GH-117894: prevent aclose()/athrow() being re-used after StopIteration (GH...

(cherry picked from commit 7d369d471cf2b067c4d795d70b75201c48b46f5b)

diff --git a/Lib/test/test_asyncgen.py b/Lib/test/test_asyncgen.py
index 9a9343781cd40c543dace0290e31ca1dd3a2b55a..ee7e3968b00b26ef331c98791f489956787a1260 100644 (file)
--- a/Lib/test/test_asyncgen.py
+++ b/Lib/test/test_asyncgen.py
@@ -395,7 +395,11 @@ class AsyncGenTest(unittest.TestCase):
             yield 123
 
         with self.assertWarns(DeprecationWarning):
-            gen().athrow(GeneratorExit, GeneratorExit(), None)
+            x = gen().athrow(GeneratorExit, GeneratorExit(), None)
+        with self.assertRaises(GeneratorExit):
+            x.send(None)
+            del x
+            gc_collect()
 
     def test_async_gen_api_01(self):
         async def gen():
@@ -1653,6 +1657,62 @@ class AsyncGenAsyncioTest(unittest.TestCase):
 
         self.loop.run_until_complete(run())
 
+    def test_async_gen_throw_same_aclose_coro_twice(self):
+        async def async_iterate():
+            yield 1
+            yield 2
+
+        it = async_iterate()
+        nxt = it.aclose()
+        with self.assertRaises(StopIteration):
+            nxt.throw(GeneratorExit)
+
+        with self.assertRaisesRegex(
+            RuntimeError,
+            r"cannot reuse already awaited aclose\(\)/athrow\(\)"
+        ):
+            nxt.throw(GeneratorExit)
+
+    def test_async_gen_throw_custom_same_aclose_coro_twice(self):
+        async def async_iterate():
+            yield 1
+            yield 2
+
+        it = async_iterate()
+
+        class MyException(Exception):
+            pass
+
+        nxt = it.aclose()
+        with self.assertRaises(MyException):
+            nxt.throw(MyException)
+
+        with self.assertRaisesRegex(
+            RuntimeError,
+            r"cannot reuse already awaited aclose\(\)/athrow\(\)"
+        ):
+            nxt.throw(MyException)
+
+    def test_async_gen_throw_custom_same_athrow_coro_twice(self):
+        async def async_iterate():
+            yield 1
+            yield 2
+
+        it = async_iterate()
+
+        class MyException(Exception):
+            pass
+
+        nxt = it.athrow(MyException)
+        with self.assertRaises(MyException):
+            nxt.throw(MyException)
+
+        with self.assertRaisesRegex(
+            RuntimeError,
+            r"cannot reuse already awaited aclose\(\)/athrow\(\)"
+        ):
+            nxt.throw(MyException)
+
     def test_async_gen_aclose_twice_with_different_coros(self):
         # Regression test for https://bugs.python.org/issue39606
         async def async_iterate():

diff --git a/Misc/NEWS.d/next/Core and Builtins/2024-04-15-13-53-59.gh-issue-117894.8LpZ6m.rst b/Misc/NEWS.d/next/Core and Builtins/2024-04-15-13-53-59.gh-issue-117894.8LpZ6m.rst
new file mode 100644 (file)
index 0000000..bd32500
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2024-04-15-13-53-59.gh-issue-117894.8LpZ6m.rst
@@ -0,0 +1 @@
+Prevent ``agen.aclose()`` objects being re-used after ``.throw()``.

diff --git a/Objects/genobject.c b/Objects/genobject.c
index bc58409c181360bccfcdd84c543220276d5ad8a5..3fc2ac083d1c15991448f12629b479a5b9251ea1 100644 (file)
--- a/Objects/genobject.c
+++ b/Objects/genobject.c
@@ -2223,7 +2223,11 @@ async_gen_athrow_throw(PyAsyncGenAThrow *o, PyObject *const *args, Py_ssize_t na
 
     retval = gen_throw((PyGenObject*)o->agt_gen, args, nargs);
     if (o->agt_args) {
-        return async_gen_unwrap_value(o->agt_gen, retval);
+        retval = async_gen_unwrap_value(o->agt_gen, retval);
+        if (retval == NULL) {
+            o->agt_state = AWAITABLE_STATE_CLOSED;
+        }
+        return retval;
     } else {
         /* aclose() mode */
         if (retval && _PyAsyncGenWrappedValue_CheckExact(retval)) {
@@ -2233,6 +2237,9 @@ async_gen_athrow_throw(PyAsyncGenAThrow *o, PyObject *const *args, Py_ssize_t na
             PyErr_SetString(PyExc_RuntimeError, ASYNC_GEN_IGNORED_EXIT_MSG);
             return NULL;
         }
+        if (retval == NULL) {
+            o->agt_state = AWAITABLE_STATE_CLOSED;
+        }
         if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration) ||
             PyErr_ExceptionMatches(PyExc_GeneratorExit))
         {