GH-117714: replace athrow().close() and asend().close() stubs with implimentations

Author: graingert

Objects/genobject.c

@@ -15,6 +15,7 @@
 #include "pycore_pystate.h"       // _PyThreadState_GET()
 
 #include "pystats.h"
+#include "pyerrors.h"
 
 static PyObject *gen_close(PyGenObject *, PyObject *);
 static PyObject *async_gen_asend_new(PyAsyncGenObject *, PyObject *);
@@ -1843,8 +1844,25 @@ async_gen_asend_throw(PyAsyncGenASend *o, PyObject *const *args, Py_ssize_t narg
 static PyObject *
 async_gen_asend_close(PyAsyncGenASend *o, PyObject *args)
 {
-    o->ags_state = AWAITABLE_STATE_CLOSED;
-    Py_RETURN_NONE;
+    PyObject *result;
+    if (o->ags_state == AWAITABLE_STATE_CLOSED) {
+        Py_RETURN_NONE;
+    }
+    result = async_gen_asend_throw(o, &PyExc_GeneratorExit, 1);
+    if (result == NULL) {
+        if (PyErr_ExceptionMatches(PyExc_StopIteration) ||
+            PyErr_ExceptionMatches(PyExc_StopAsyncIteration) ||
+            PyErr_ExceptionMatches(PyExc_GeneratorExit))
+        {
+            PyErr_Clear();
+            Py_RETURN_NONE;
+        }
+        return result;
+    } else {
+        Py_DECREF(result);
+        PyErr_SetString(PyExc_RuntimeError, "coroutine ignored GeneratorExit");
+        return NULL;
+    }
 }
 
 static void
@@ -2288,8 +2306,25 @@ async_gen_athrow_iternext(PyAsyncGenAThrow *o)
 static PyObject *
 async_gen_athrow_close(PyAsyncGenAThrow *o, PyObject *args)
 {
-    o->agt_state = AWAITABLE_STATE_CLOSED;
-    Py_RETURN_NONE;
+    PyObject *result;
+    if (o->agt_state == AWAITABLE_STATE_CLOSED) {
+        Py_RETURN_NONE;
+    }
+    result = async_gen_athrow_throw(o, &PyExc_GeneratorExit, 1);
+    if (result == NULL) {
+        if (PyErr_ExceptionMatches(PyExc_StopIteration) ||
+            PyErr_ExceptionMatches(PyExc_StopAsyncIteration) ||
+            PyErr_ExceptionMatches(PyExc_GeneratorExit))
+        {
+            PyErr_Clear();
+            Py_RETURN_NONE;
+        }
+        return result;
+    } else {
+        Py_DECREF(result);
+        PyErr_SetString(PyExc_RuntimeError, "coroutine ignored GeneratorExit");
+        return NULL;
+    }
 }