bpo-42085: Introduce dedicated entry in PyAsyncMethods for sending values (#22780)

Include/abstract.h

@@ -339,11 +339,6 @@ PyAPI_FUNC(int) PyIter_Check(PyObject *);
 PyAPI_FUNC(PyObject *) PyIter_Next(PyObject *);
 
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030A0000
-typedef enum {
-    PYGEN_RETURN = 0,
-    PYGEN_ERROR = -1,
-    PYGEN_NEXT = 1,
-} PySendResult;
 
 /* Takes generator, coroutine or iterator object and sends the value into it.
    Returns:

Include/cpython/object.h

@@ -167,10 +167,13 @@ typedef struct {
     objobjargproc mp_ass_subscript;
 } PyMappingMethods;
 
+typedef PySendResult (*sendfunc)(PyObject *iter, PyObject *value, PyObject **result);
+
 typedef struct {
     unaryfunc am_await;
     unaryfunc am_aiter;
     unaryfunc am_anext;
+    sendfunc am_send;
 } PyAsyncMethods;
 
 typedef struct {

Include/object.h

@@ -356,6 +356,11 @@ given type object has a specified feature.
 /* Type is abstract and cannot be instantiated */
 #define Py_TPFLAGS_IS_ABSTRACT (1UL << 20)
 
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030A0000
+/* Type has am_send entry in tp_as_async slot */
+#define Py_TPFLAGS_HAVE_AM_SEND (1UL << 21)
+#endif
+
 /* These flags are used to determine if a type is a subclass. */
 #define Py_TPFLAGS_LONG_SUBCLASS        (1UL << 24)
 #define Py_TPFLAGS_LIST_SUBCLASS        (1UL << 25)
@@ -582,6 +587,15 @@ PyAPI_DATA(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */
 #define Py_GT 4
 #define Py_GE 5
 
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030A0000
+/* Result of calling PyIter_Send */
+typedef enum {
+    PYGEN_RETURN = 0,
+    PYGEN_ERROR = -1,
+    PYGEN_NEXT = 1,
+} PySendResult;
+#endif
+
 /*
  * Macro for implementing rich comparisons
  *

Include/typeslots.h

@@ -88,3 +88,7 @@
 /* New in 3.5 */
 #define Py_tp_finalize 80
 #endif
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x030A0000
+/* New in 3.10 */
+#define Py_am_send 81
+#endif