bpo-45123: PyAiter_Check and PyObject_GetAiter fix & rename. (GH-28194)

Fix PyAiter_Check to only check for the `__anext__` presense (not for
`__aiter__`). Rename `PyAiter_Check()` to `PyAIter_Check()`,
`PyObject_GetAiter()` -> `PyObject_GetAIter()`.

Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>

Doc/c-api/iter.rst

@@ -12,7 +12,7 @@ There are two functions specifically for working with iterators.
    Return non-zero if the object *o* supports the iterator protocol, and ``0``
    otherwise.  This function always succeeds.
 
-.. c:function:: int PyAiter_Check(PyObject *o)
+.. c:function:: int PyAIter_Check(PyObject *o)
 
    Returns non-zero if the object 'obj' provides :class:`AsyncIterator`
    protocols, and ``0`` otherwise.  This function always succeeds.

Doc/c-api/object.rst

@@ -358,7 +358,7 @@ Object Protocol
    iterated.
 
 
-.. c:function:: PyObject* PyObject_GetAiter(PyObject *o)
+.. c:function:: PyObject* PyObject_GetAIter(PyObject *o)
 
    This is the equivalent to the Python expression ``aiter(o)``. Takes an
    :class:`AsyncIterable` object and returns an :class:`AsyncIterator` for it.

Doc/data/refcounts.dat

@@ -1073,8 +1073,8 @@ PyInterpreterState_New:PyInterpreterState*:::
 PyIter_Check:int:::
 PyIter_Check:PyObject*:o:0:
 
-PyAiter_Check:int:::
-PyAiter_Check:PyObject*:o:0:
+PyAIter_Check:int:::
+PyAIter_Check:PyObject*:o:0:
 
 PyIter_Next:PyObject*::+1:
 PyIter_Next:PyObject*:o:0:
@@ -1700,8 +1700,8 @@ PyObject_GetItem:PyObject*:key:0:
 PyObject_GetIter:PyObject*::+1:
 PyObject_GetIter:PyObject*:o:0:
 
-PyObject_GetAiter:PyObject*::+1:
-PyObject_GetAiter:PyObject*:o:0:
+PyObject_GetAIter:PyObject*::+1:
+PyObject_GetAIter:PyObject*:o:0:
 
 PyObject_HasAttr:int:::
 PyObject_HasAttr:PyObject*:o:0:

Doc/data/stable_abi.dat

@@ -1,5 +1,5 @@
 role,name,added,ifdef_note
-function,PyAiter_Check,3.10,
+function,PyAIter_Check,3.10,
 function,PyArg_Parse,3.2,
 function,PyArg_ParseTuple,3.2,
 function,PyArg_ParseTupleAndKeywords,3.2,
@@ -491,7 +491,7 @@ function,PyObject_GenericGetAttr,3.2,
 function,PyObject_GenericGetDict,3.10,
 function,PyObject_GenericSetAttr,3.2,
 function,PyObject_GenericSetDict,3.7,
-function,PyObject_GetAiter,3.10,
+function,PyObject_GetAIter,3.10,
 function,PyObject_GetAttr,3.2,
 function,PyObject_GetAttrString,3.2,
 function,PyObject_GetItem,3.2,

Include/abstract.h

@@ -374,7 +374,7 @@ PyAPI_FUNC(PyObject *) PyObject_GetIter(PyObject *);
 /* Takes an AsyncIterable object and returns an AsyncIterator for it.
    This is typically a new iterator but if the argument is an AsyncIterator,
    this returns itself. */
-PyAPI_FUNC(PyObject *) PyObject_GetAiter(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_GetAIter(PyObject *);
 
 /* Returns non-zero if the object 'obj' provides iterator protocols, and 0 otherwise.
 
@@ -384,7 +384,7 @@ PyAPI_FUNC(int) PyIter_Check(PyObject *);
 /* Returns non-zero if the object 'obj' provides AsyncIterator protocols, and 0 otherwise.
 
    This function always succeeds. */
-PyAPI_FUNC(int) PyAiter_Check(PyObject *);
+PyAPI_FUNC(int) PyAIter_Check(PyObject *);
 
 /* Takes an iterator object and calls its tp_iternext slot,
    returning the next value.

Misc/NEWS.d/next/Core and Builtins/2021-09-06-21-52-45.bpo-45123.8Eh9iI.rst

@@ -0,0 +1,3 @@
+Fix PyAiter_Check to only check for the __anext__ presence (not for
+__aiter__). Rename PyAiter_Check to PyAIter_Check, PyObject_GetAiter ->
+PyObject_GetAIter.

Misc/stable_abi.txt

@@ -2110,9 +2110,9 @@ function _Py_IncRef
 function _Py_DecRef
     added 3.10
     abi_only
-function PyAiter_Check
+function PyAIter_Check
     added 3.10
-function PyObject_GetAiter
+function PyObject_GetAIter
     added 3.10
 data PyExc_EncodingWarning
     added 3.10

Objects/abstract.c

@@ -2816,18 +2816,18 @@ PyObject_GetIter(PyObject *o)
 }
 
 PyObject *
-PyObject_GetAiter(PyObject *o) {
+PyObject_GetAIter(PyObject *o) {
     PyTypeObject *t = Py_TYPE(o);
     unaryfunc f;
 
     if (t->tp_as_async == NULL || t->tp_as_async->am_aiter == NULL) {
-        return type_error("'%.200s' object is not an AsyncIterable", o);
+        return type_error("'%.200s' object is not an async iterable", o);
     }
     f = t->tp_as_async->am_aiter;
     PyObject *it = (*f)(o);
-    if (it != NULL && !PyAiter_Check(it)) {
+    if (it != NULL && !PyAIter_Check(it)) {
         PyErr_Format(PyExc_TypeError,
-                     "aiter() returned non-AsyncIterator of type '%.100s'",
+                     "aiter() returned not an async iterator of type '%.100s'",
                      Py_TYPE(it)->tp_name);
         Py_DECREF(it);
         it = NULL;
@@ -2844,12 +2844,10 @@ PyIter_Check(PyObject *obj)
 }
 
 int
-PyAiter_Check(PyObject *obj)
+PyAIter_Check(PyObject *obj)
 {
     PyTypeObject *tp = Py_TYPE(obj);
     return (tp->tp_as_async != NULL &&
-            tp->tp_as_async->am_aiter != NULL &&
-            tp->tp_as_async->am_aiter != &_PyObject_NextNotImplemented &&
             tp->tp_as_async->am_anext != NULL &&
             tp->tp_as_async->am_anext != &_PyObject_NextNotImplemented);
 }

PC/python3dll.c

@@ -86,7 +86,7 @@ EXPORT_FUNC(Py_SetPythonHome)
 EXPORT_FUNC(Py_SetRecursionLimit)
 EXPORT_FUNC(Py_VaBuildValue)
 EXPORT_FUNC(Py_XNewRef)
-EXPORT_FUNC(PyAiter_Check)
+EXPORT_FUNC(PyAIter_Check)
 EXPORT_FUNC(PyArg_Parse)
 EXPORT_FUNC(PyArg_ParseTuple)
 EXPORT_FUNC(PyArg_ParseTupleAndKeywords)
@@ -443,7 +443,7 @@ EXPORT_FUNC(PyObject_GenericGetAttr)
 EXPORT_FUNC(PyObject_GenericGetDict)
 EXPORT_FUNC(PyObject_GenericSetAttr)
 EXPORT_FUNC(PyObject_GenericSetDict)
-EXPORT_FUNC(PyObject_GetAiter)
+EXPORT_FUNC(PyObject_GetAIter)
 EXPORT_FUNC(PyObject_GetAttr)
 EXPORT_FUNC(PyObject_GetAttrString)
 EXPORT_FUNC(PyObject_GetItem)

Python/bltinmodule.c

@@ -1610,7 +1610,7 @@ static PyObject *
 builtin_aiter(PyObject *module, PyObject *async_iterable)
 /*[clinic end generated code: output=1bae108d86f7960e input=473993d0cacc7d23]*/
 {
-    return PyObject_GetAiter(async_iterable);
+    return PyObject_GetAIter(async_iterable);
 }
 
 PyObject *PyAnextAwaitable_New(PyObject *, PyObject *);