/src/cpython/Objects/iterobject.c

Source (jump to first uncovered line)
/* Iterator objects */

#include "Python.h"
#include "pycore_abstract.h"      // _PyObject_HasLen()
#include "pycore_call.h"          // _PyObject_CallNoArgs()
#include "pycore_ceval.h"         // _PyEval_GetBuiltin()
#include "pycore_genobject.h"     // _PyCoro_GetAwaitableIter()
#include "pycore_object.h"        // _PyObject_GC_TRACK()


typedef struct {
    PyObject_HEAD
    Py_ssize_t it_index;
    PyObject *it_seq; /* Set to NULL when iterator is exhausted */
} seqiterobject;

PyObject *
PySeqIter_New(PyObject *seq)
{
    seqiterobject *it;

    if (!PySequence_Check(seq)) {
        PyErr_BadInternalCall();
        return NULL;
    }
    it = PyObject_GC_New(seqiterobject, &PySeqIter_Type);
    if (it == NULL)
        return NULL;
    it->it_index = 0;
    it->it_seq = Py_NewRef(seq);
    _PyObject_GC_TRACK(it);
    return (PyObject *)it;
}

static void
iter_dealloc(PyObject *op)
{
    seqiterobject *it = (seqiterobject*)op;
    _PyObject_GC_UNTRACK(it);
    Py_XDECREF(it->it_seq);
    PyObject_GC_Del(it);
}

static int
iter_traverse(PyObject *op, visitproc visit, void *arg)
{
    seqiterobject *it = (seqiterobject*)op;
    Py_VISIT(it->it_seq);
    return 0;
}

static PyObject *
iter_iternext(PyObject *iterator)
{
    seqiterobject *it;
    PyObject *seq;
    PyObject *result;

    assert(PySeqIter_Check(iterator));
    it = (seqiterobject *)iterator;
    seq = it->it_seq;
    if (seq == NULL)
        return NULL;
    if (it->it_index == PY_SSIZE_T_MAX) {
        PyErr_SetString(PyExc_OverflowError,
                        "iter index too large");
        return NULL;
    }

    result = PySequence_GetItem(seq, it->it_index);
    if (result != NULL) {
        it->it_index++;
        return result;
    }
    if (PyErr_ExceptionMatches(PyExc_IndexError) ||
        PyErr_ExceptionMatches(PyExc_StopIteration))
    {
        PyErr_Clear();
        it->it_seq = NULL;
        Py_DECREF(seq);
    }
    return NULL;
}

static PyObject *
iter_len(PyObject *op, PyObject *Py_UNUSED(ignored))
{
    seqiterobject *it = (seqiterobject*)op;
    Py_ssize_t seqsize, len;

    if (it->it_seq) {
        if (_PyObject_HasLen(it->it_seq)) {
            seqsize = PySequence_Size(it->it_seq);
            if (seqsize == -1)
                return NULL;
        }
        else {
            Py_RETURN_NOTIMPLEMENTED;
        }
        len = seqsize - it->it_index;
        if (len >= 0)
            return PyLong_FromSsize_t(len);
    }
    return PyLong_FromLong(0);
}

PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it)).");

static PyObject *
iter_reduce(PyObject *op, PyObject *Py_UNUSED(ignored))
{
    seqiterobject *it = (seqiterobject*)op;
    PyObject *iter = _PyEval_GetBuiltin(&_Py_ID(iter));

    /* _PyEval_GetBuiltin can invoke arbitrary code,
     * call must be before access of iterator pointers.
     * see issue #101765 */

    if (it->it_seq != NULL)
        return Py_BuildValue("N(O)n", iter, it->it_seq, it->it_index);
    else
        return Py_BuildValue("N(())", iter);
}

PyDoc_STRVAR(reduce_doc, "Return state information for pickling.");

static PyObject *
iter_setstate(PyObject *op, PyObject *state)
{
    seqiterobject *it = (seqiterobject*)op;
    Py_ssize_t index = PyLong_AsSsize_t(state);
    if (index == -1 && PyErr_Occurred())
        return NULL;
    if (it->it_seq != NULL) {
        if (index < 0)
            index = 0;
        it->it_index = index;
    }
    Py_RETURN_NONE;
}

PyDoc_STRVAR(setstate_doc, "Set state information for unpickling.");

static PyMethodDef seqiter_methods[] = {
    {"__length_hint__", iter_len, METH_NOARGS, length_hint_doc},
    {"__reduce__", iter_reduce, METH_NOARGS, reduce_doc},
    {"__setstate__", iter_setstate, METH_O, setstate_doc},
    {NULL,              NULL}           /* sentinel */
};

PyTypeObject PySeqIter_Type = {
    PyVarObject_HEAD_INIT(&PyType_Type, 0)
    "iterator",                                 /* tp_name */
    sizeof(seqiterobject),                      /* tp_basicsize */
    0,                                          /* tp_itemsize */
    /* methods */
    iter_dealloc,                               /* tp_dealloc */
    0,                                          /* tp_vectorcall_offset */
    0,                                          /* tp_getattr */
    0,                                          /* tp_setattr */
    0,                                          /* tp_as_async */
    0,                                          /* tp_repr */
    0,                                          /* tp_as_number */
    0,                                          /* tp_as_sequence */
    0,                                          /* tp_as_mapping */
    0,                                          /* tp_hash */
    0,                                          /* tp_call */
    0,                                          /* tp_str */
    PyObject_GenericGetAttr,                    /* tp_getattro */
    0,                                          /* tp_setattro */
    0,                                          /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,    /* tp_flags */
    0,                                          /* tp_doc */
    iter_traverse,                              /* tp_traverse */
    0,                                          /* tp_clear */
    0,                                          /* tp_richcompare */
    0,                                          /* tp_weaklistoffset */
    PyObject_SelfIter,                          /* tp_iter */
    iter_iternext,                              /* tp_iternext */
    seqiter_methods,                            /* tp_methods */
    0,                                          /* tp_members */
};

/* -------------------------------------- */

typedef struct {
    PyObject_HEAD
    PyObject *it_callable; /* Set to NULL when iterator is exhausted */
    PyObject *it_sentinel; /* Set to NULL when iterator is exhausted */
} calliterobject;

PyObject *
PyCallIter_New(PyObject *callable, PyObject *sentinel)
{
    calliterobject *it;
    it = PyObject_GC_New(calliterobject, &PyCallIter_Type);
    if (it == NULL)
        return NULL;
    it->it_callable = Py_NewRef(callable);
    it->it_sentinel = Py_NewRef(sentinel);
    _PyObject_GC_TRACK(it);
    return (PyObject *)it;
}
static void
calliter_dealloc(PyObject *op)
{
    calliterobject *it = (calliterobject*)op;
    _PyObject_GC_UNTRACK(it);
    Py_XDECREF(it->it_callable);
    Py_XDECREF(it->it_sentinel);
    PyObject_GC_Del(it);
}

static int
calliter_traverse(PyObject *op, visitproc visit, void *arg)
{
    calliterobject *it = (calliterobject*)op;
    Py_VISIT(it->it_callable);
    Py_VISIT(it->it_sentinel);
    return 0;
}

static PyObject *
calliter_iternext(PyObject *op)
{
    calliterobject *it = (calliterobject*)op;
    PyObject *result;

    if (it->it_callable == NULL) {
        return NULL;
    }

    result = _PyObject_CallNoArgs(it->it_callable);
    if (result != NULL && it->it_sentinel != NULL){
        int ok;

        ok = PyObject_RichCompareBool(it->it_sentinel, result, Py_EQ);
        if (ok == 0) {
            return result; /* Common case, fast path */
        }

        if (ok > 0) {
            Py_CLEAR(it->it_callable);
            Py_CLEAR(it->it_sentinel);
        }
    }
    else if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
        PyErr_Clear();
        Py_CLEAR(it->it_callable);
        Py_CLEAR(it->it_sentinel);
    }
    Py_XDECREF(result);
    return NULL;
}

static PyObject *
calliter_reduce(PyObject *op, PyObject *Py_UNUSED(ignored))
{
    calliterobject *it = (calliterobject*)op;
    PyObject *iter = _PyEval_GetBuiltin(&_Py_ID(iter));

    /* _PyEval_GetBuiltin can invoke arbitrary code,
     * call must be before access of iterator pointers.
     * see issue #101765 */

    if (it->it_callable != NULL && it->it_sentinel != NULL)
        return Py_BuildValue("N(OO)", iter, it->it_callable, it->it_sentinel);
    else
        return Py_BuildValue("N(())", iter);
}

static PyMethodDef calliter_methods[] = {
    {"__reduce__", calliter_reduce, METH_NOARGS, reduce_doc},
    {NULL,              NULL}           /* sentinel */
};

PyTypeObject PyCallIter_Type = {
    PyVarObject_HEAD_INIT(&PyType_Type, 0)
    "callable_iterator",                        /* tp_name */
    sizeof(calliterobject),                     /* tp_basicsize */
    0,                                          /* tp_itemsize */
    /* methods */
    calliter_dealloc,                           /* tp_dealloc */
    0,                                          /* tp_vectorcall_offset */
    0,                                          /* tp_getattr */
    0,                                          /* tp_setattr */
    0,                                          /* tp_as_async */
    0,                                          /* tp_repr */
    0,                                          /* tp_as_number */
    0,                                          /* tp_as_sequence */
    0,                                          /* tp_as_mapping */
    0,                                          /* tp_hash */
    0,                                          /* tp_call */
    0,                                          /* tp_str */
    PyObject_GenericGetAttr,                    /* tp_getattro */
    0,                                          /* tp_setattro */
    0,                                          /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,    /* tp_flags */
    0,                                          /* tp_doc */
    calliter_traverse,                          /* tp_traverse */
    0,                                          /* tp_clear */
    0,                                          /* tp_richcompare */
    0,                                          /* tp_weaklistoffset */
    PyObject_SelfIter,                          /* tp_iter */
    calliter_iternext,                          /* tp_iternext */
    calliter_methods,                           /* tp_methods */
};


/* -------------------------------------- */

typedef struct {
    PyObject_HEAD
    PyObject *wrapped;
    PyObject *default_value;
} anextawaitableobject;

#define anextawaitableobject_CAST(op)   ((anextawaitableobject *)(op))

static void
anextawaitable_dealloc(PyObject *op)
{
    anextawaitableobject *obj = anextawaitableobject_CAST(op);
    _PyObject_GC_UNTRACK(obj);
    Py_XDECREF(obj->wrapped);
    Py_XDECREF(obj->default_value);
    PyObject_GC_Del(obj);
}

static int
anextawaitable_traverse(PyObject *op, visitproc visit, void *arg)
{
    anextawaitableobject *obj = anextawaitableobject_CAST(op);
    Py_VISIT(obj->wrapped);
    Py_VISIT(obj->default_value);
    return 0;
}

static PyObject *
anextawaitable_getiter(anextawaitableobject *obj)
{
    assert(obj->wrapped != NULL);
    PyObject *awaitable = _PyCoro_GetAwaitableIter(obj->wrapped);
    if (awaitable == NULL) {
        return NULL;
    }
    if (Py_TYPE(awaitable)->tp_iternext == NULL) {
        /* _PyCoro_GetAwaitableIter returns a Coroutine, a Generator,
         * or an iterator. Of these, only coroutines lack tp_iternext.
         */
        assert(PyCoro_CheckExact(awaitable));
        unaryfunc getter = Py_TYPE(awaitable)->tp_as_async->am_await;
        PyObject *new_awaitable = getter(awaitable);
        if (new_awaitable == NULL) {
            Py_DECREF(awaitable);
            return NULL;
        }
        Py_SETREF(awaitable, new_awaitable);
        if (!PyIter_Check(awaitable)) {
            PyErr_SetString(PyExc_TypeError,
                            "__await__ returned a non-iterable");
            Py_DECREF(awaitable);
            return NULL;
        }
    }
    return awaitable;
}

static PyObject *
anextawaitable_iternext(PyObject *op)
{
    /* Consider the following class:
     *
     *     class A:
     *         async def __anext__(self):
     *             ...
     *     a = A()
     *
     * Then `await anext(a)` should call
     * a.__anext__().__await__().__next__()
     *
     * On the other hand, given
     *
     *     async def agen():
     *         yield 1
     *         yield 2
     *     gen = agen()
     *
     * Then `await anext(gen)` can just call
     * gen.__anext__().__next__()
     */
    anextawaitableobject *obj = anextawaitableobject_CAST(op);
    PyObject *awaitable = anextawaitable_getiter(obj);
    if (awaitable == NULL) {
        return NULL;
    }
    PyObject *result = (*Py_TYPE(awaitable)->tp_iternext)(awaitable);
    Py_DECREF(awaitable);
    if (result != NULL) {
        return result;
    }
    if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration)) {
        PyErr_Clear();
        _PyGen_SetStopIterationValue(obj->default_value);
    }
    return NULL;
}


static PyObject *
anextawaitable_proxy(anextawaitableobject *obj, char *meth, PyObject *arg)
{
    PyObject *awaitable = anextawaitable_getiter(obj);
    if (awaitable == NULL) {
        return NULL;
    }
    // When specified, 'arg' may be a tuple (if coming from a METH_VARARGS
    // method) or a single object (if coming from a METH_O method).
    PyObject *ret = arg == NULL
        ? PyObject_CallMethod(awaitable, meth, NULL)
        : PyObject_CallMethod(awaitable, meth, "O", arg);
    Py_DECREF(awaitable);
    if (ret != NULL) {
        return ret;
    }
    if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration)) {
        /* `anextawaitableobject` is only used by `anext()` when
         * a default value is provided. So when we have a StopAsyncIteration
         * exception we replace it with a `StopIteration(default)`, as if
         * it was the return value of `__anext__()` coroutine.
         */
        PyErr_Clear();
        _PyGen_SetStopIterationValue(obj->default_value);
    }
    return NULL;
}


static PyObject *
anextawaitable_send(PyObject *op, PyObject *arg)
{
    anextawaitableobject *obj = anextawaitableobject_CAST(op);
    return anextawaitable_proxy(obj, "send", arg);
}


static PyObject *
anextawaitable_throw(PyObject *op, PyObject *args)
{
    anextawaitableobject *obj = anextawaitableobject_CAST(op);
    return anextawaitable_proxy(obj, "throw", args);
}


static PyObject *
anextawaitable_close(PyObject *op, PyObject *Py_UNUSED(dummy))
{
    anextawaitableobject *obj = anextawaitableobject_CAST(op);
    return anextawaitable_proxy(obj, "close", NULL);
}


PyDoc_STRVAR(send_doc,
"send(arg) -> send 'arg' into the wrapped iterator,\n\
return next yielded value or raise StopIteration.");


PyDoc_STRVAR(throw_doc,
"throw(value)\n\
throw(typ[,val[,tb]])\n\
\n\
raise exception in the wrapped iterator, return next yielded value\n\
or raise StopIteration.\n\
the (type, val, tb) signature is deprecated, \n\
and may be removed in a future version of Python.");


PyDoc_STRVAR(close_doc,
"close() -> raise GeneratorExit inside generator.");


static PyMethodDef anextawaitable_methods[] = {
    {"send", anextawaitable_send, METH_O, send_doc},
    {"throw", anextawaitable_throw, METH_VARARGS, throw_doc},
    {"close", anextawaitable_close, METH_NOARGS, close_doc},
    {NULL, NULL}        /* Sentinel */
};


static PyAsyncMethods anextawaitable_as_async = {
    PyObject_SelfIter,                          /* am_await */
    0,                                          /* am_aiter */
    0,                                          /* am_anext */
    0,                                          /* am_send  */
};

PyTypeObject _PyAnextAwaitable_Type = {
    PyVarObject_HEAD_INIT(&PyType_Type, 0)
    "anext_awaitable",                          /* tp_name */
    sizeof(anextawaitableobject),               /* tp_basicsize */
    0,                                          /* tp_itemsize */
    /* methods */
    anextawaitable_dealloc,                     /* tp_dealloc */
    0,                                          /* tp_vectorcall_offset */
    0,                                          /* tp_getattr */
    0,                                          /* tp_setattr */
    &anextawaitable_as_async,                   /* tp_as_async */
    0,                                          /* tp_repr */
    0,                                          /* tp_as_number */
    0,                                          /* tp_as_sequence */
    0,                                          /* tp_as_mapping */
    0,                                          /* tp_hash */
    0,                                          /* tp_call */
    0,                                          /* tp_str */
    PyObject_GenericGetAttr,                    /* tp_getattro */
    0,                                          /* tp_setattro */
    0,                                          /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,    /* tp_flags */
    0,                                          /* tp_doc */
    anextawaitable_traverse,                    /* tp_traverse */
    0,                                          /* tp_clear */
    0,                                          /* tp_richcompare */
    0,                                          /* tp_weaklistoffset */
    PyObject_SelfIter,                          /* tp_iter */
    anextawaitable_iternext,                    /* tp_iternext */
    anextawaitable_methods,                     /* tp_methods */
};

PyObject *
PyAnextAwaitable_New(PyObject *awaitable, PyObject *default_value)
{
    anextawaitableobject *anext = PyObject_GC_New(
            anextawaitableobject, &_PyAnextAwaitable_Type);
    if (anext == NULL) {
        return NULL;
    }
    anext->wrapped = Py_NewRef(awaitable);
    anext->default_value = Py_NewRef(default_value);
    _PyObject_GC_TRACK(anext);
    return (PyObject *)anext;
}

Coverage Report

Created: 2025-07-11 06:24

Line	Count	Source (jump to first uncovered line)
1		/* Iterator objects */
2
3		#include "Python.h"
4		#include "pycore_abstract.h" // _PyObject_HasLen()
5		#include "pycore_call.h" // _PyObject_CallNoArgs()
6		#include "pycore_ceval.h" // _PyEval_GetBuiltin()
7		#include "pycore_genobject.h" // _PyCoro_GetAwaitableIter()
8		#include "pycore_object.h" // _PyObject_GC_TRACK()
9
10
11		typedef struct {
12		PyObject_HEAD
13		Py_ssize_t it_index;
14		PyObject it_seq; / Set to NULL when iterator is exhausted */
15		} seqiterobject;
16
17		PyObject *
18		PySeqIter_New(PyObject *seq)
19	595	{
20	595	seqiterobject *it;
21
22	595	if (!PySequence_Check(seq)) {
23	0	PyErr_BadInternalCall();
24	0	return NULL;
25	0	}
26	595	it = PyObject_GC_New(seqiterobject, &PySeqIter_Type);
27	595	if (it == NULL)
28	0	return NULL;
29	595	it->it_index = 0;
30	595	it->it_seq = Py_NewRef(seq);
31	595	_PyObject_GC_TRACK(it);
32	595	return (PyObject *)it;
33	595	}
34
35		static void
36		iter_dealloc(PyObject *op)
37	595	{
38	595	seqiterobject it = (seqiterobject)op;
39	595	_PyObject_GC_UNTRACK(it);
40	595	Py_XDECREF(it->it_seq);
41	595	PyObject_GC_Del(it);
42	595	}
43
44		static int
45		iter_traverse(PyObject op, visitproc visit, void arg)
46	0	{
47	0	seqiterobject it = (seqiterobject)op;
48	0	Py_VISIT(it->it_seq);
49	0	return 0;
50	0	}
51
52		static PyObject *
53		iter_iternext(PyObject *iterator)
54	1.38k	{
55	1.38k	seqiterobject *it;
56	1.38k	PyObject *seq;
57	1.38k	PyObject *result;
58
59	1.38k	assert(PySeqIter_Check(iterator));
60	1.38k	it = (seqiterobject *)iterator;
61	1.38k	seq = it->it_seq;
62	1.38k	if (seq == NULL)
63	0	return NULL;
64	1.38k	if (it->it_index == PY_SSIZE_T_MAX) {
65	0	PyErr_SetString(PyExc_OverflowError,
66	0	"iter index too large");
67	0	return NULL;
68	0	}
69
70	1.38k	result = PySequence_GetItem(seq, it->it_index);
71	1.38k	if (result != NULL) {
72	787	it->it_index++;
73	787	return result;
74	787	}
75	595	if (PyErr_ExceptionMatches(PyExc_IndexError) \|\|
76	595	PyErr_ExceptionMatches(PyExc_StopIteration))
77	595	{
78	595	PyErr_Clear();
79	595	it->it_seq = NULL;
80	595	Py_DECREF(seq);
81	595	}
82	595	return NULL;
83	1.38k	}
84
85		static PyObject *
86		iter_len(PyObject op, PyObject Py_UNUSED(ignored))
87	10	{
88	10	seqiterobject it = (seqiterobject)op;
89	10	Py_ssize_t seqsize, len;
90
91	10	if (it->it_seq) {
92	10	if (_PyObject_HasLen(it->it_seq)) {
93	10	seqsize = PySequence_Size(it->it_seq);
94	10	if (seqsize == -1)
95	0	return NULL;
96	10	}
97	0	else {
98	0	Py_RETURN_NOTIMPLEMENTED;
99	0	}
100	10	len = seqsize - it->it_index;
101	10	if (len >= 0)
102	10	return PyLong_FromSsize_t(len);
103	10	}
104	0	return PyLong_FromLong(0);
105	10	}
106
107		PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it)).");
108
109		static PyObject *
110		iter_reduce(PyObject op, PyObject Py_UNUSED(ignored))
111	0	{
112	0	seqiterobject it = (seqiterobject)op;
113	0	PyObject *iter = _PyEval_GetBuiltin(&_Py_ID(iter));
114
115		/* _PyEval_GetBuiltin can invoke arbitrary code,
116		* call must be before access of iterator pointers.
117		* see issue #101765 */
118
119	0	if (it->it_seq != NULL)
120	0	return Py_BuildValue("N(O)n", iter, it->it_seq, it->it_index);
121	0	else
122	0	return Py_BuildValue("N(())", iter);
123	0	}
124
125		PyDoc_STRVAR(reduce_doc, "Return state information for pickling.");
126
127		static PyObject *
128		iter_setstate(PyObject op, PyObject state)
129	0	{
130	0	seqiterobject it = (seqiterobject)op;
131	0	Py_ssize_t index = PyLong_AsSsize_t(state);
132	0	if (index == -1 && PyErr_Occurred())
133	0	return NULL;
134	0	if (it->it_seq != NULL) {
135	0	if (index < 0)
136	0	index = 0;
137	0	it->it_index = index;
138	0	}
139	0	Py_RETURN_NONE;
140	0	}
141
142		PyDoc_STRVAR(setstate_doc, "Set state information for unpickling.");
143
144		static PyMethodDef seqiter_methods[] = {
145		{"__length_hint__", iter_len, METH_NOARGS, length_hint_doc},
146		{"__reduce__", iter_reduce, METH_NOARGS, reduce_doc},
147		{"__setstate__", iter_setstate, METH_O, setstate_doc},
148		{NULL, NULL} /* sentinel */
149		};
150
151		PyTypeObject PySeqIter_Type = {
152		PyVarObject_HEAD_INIT(&PyType_Type, 0)
153		"iterator", /* tp_name */
154		sizeof(seqiterobject), /* tp_basicsize */
155		0, /* tp_itemsize */
156		/* methods */
157		iter_dealloc, /* tp_dealloc */
158		0, /* tp_vectorcall_offset */
159		0, /* tp_getattr */
160		0, /* tp_setattr */
161		0, /* tp_as_async */
162		0, /* tp_repr */
163		0, /* tp_as_number */
164		0, /* tp_as_sequence */
165		0, /* tp_as_mapping */
166		0, /* tp_hash */
167		0, /* tp_call */
168		0, /* tp_str */
169		PyObject_GenericGetAttr, /* tp_getattro */
170		0, /* tp_setattro */
171		0, /* tp_as_buffer */
172		Py_TPFLAGS_DEFAULT \| Py_TPFLAGS_HAVE_GC, /* tp_flags */
173		0, /* tp_doc */
174		iter_traverse, /* tp_traverse */
175		0, /* tp_clear */
176		0, /* tp_richcompare */
177		0, /* tp_weaklistoffset */
178		PyObject_SelfIter, /* tp_iter */
179		iter_iternext, /* tp_iternext */
180		seqiter_methods, /* tp_methods */
181		0, /* tp_members */
182		};
183
184		/* -------------------------------------- */
185
186		typedef struct {
187		PyObject_HEAD
188		PyObject it_callable; / Set to NULL when iterator is exhausted */
189		PyObject it_sentinel; / Set to NULL when iterator is exhausted */
190		} calliterobject;
191
192		PyObject *
193		PyCallIter_New(PyObject callable, PyObject sentinel)
194	228k	{
195	228k	calliterobject *it;
196	228k	it = PyObject_GC_New(calliterobject, &PyCallIter_Type);
197	228k	if (it == NULL)
198	0	return NULL;
199	228k	it->it_callable = Py_NewRef(callable);
200	228k	it->it_sentinel = Py_NewRef(sentinel);
201	228k	_PyObject_GC_TRACK(it);
202	228k	return (PyObject *)it;
203	228k	}
204		static void
205		calliter_dealloc(PyObject *op)
206	228k	{
207	228k	calliterobject it = (calliterobject)op;
208	228k	_PyObject_GC_UNTRACK(it);
209	228k	Py_XDECREF(it->it_callable);
210	228k	Py_XDECREF(it->it_sentinel);
211	228k	PyObject_GC_Del(it);
212	228k	}
213
214		static int
215		calliter_traverse(PyObject op, visitproc visit, void arg)
216	318	{
217	318	calliterobject it = (calliterobject)op;
218	318	Py_VISIT(it->it_callable);
219	318	Py_VISIT(it->it_sentinel);
220	318	return 0;
221	318	}
222
223		static PyObject *
224		calliter_iternext(PyObject *op)
225	2.01M	{
226	2.01M	calliterobject it = (calliterobject)op;
227	2.01M	PyObject *result;
228
229	2.01M	if (it->it_callable == NULL) {
230	0	return NULL;
231	0	}
232
233	2.01M	result = _PyObject_CallNoArgs(it->it_callable);
234	2.01M	if (result != NULL && it->it_sentinel != NULL){
235	2.01M	int ok;
236
237	2.01M	ok = PyObject_RichCompareBool(it->it_sentinel, result, Py_EQ);
238	2.01M	if (ok == 0) {
239	1.79M	return result; /* Common case, fast path */
240	1.79M	}
241
242	228k	if (ok > 0) {
243	228k	Py_CLEAR(it->it_callable);
244	228k	Py_CLEAR(it->it_sentinel);
245	228k	}
246	228k	}
247	0	else if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
248	0	PyErr_Clear();
249	0	Py_CLEAR(it->it_callable);
250	0	Py_CLEAR(it->it_sentinel);
251	0	}
252	228k	Py_XDECREF(result);
253	228k	return NULL;
254	2.01M	}
255
256		static PyObject *
257		calliter_reduce(PyObject op, PyObject Py_UNUSED(ignored))
258	0	{
259	0	calliterobject it = (calliterobject)op;
260	0	PyObject *iter = _PyEval_GetBuiltin(&_Py_ID(iter));
261
262		/* _PyEval_GetBuiltin can invoke arbitrary code,
263		* call must be before access of iterator pointers.
264		* see issue #101765 */
265
266	0	if (it->it_callable != NULL && it->it_sentinel != NULL)
267	0	return Py_BuildValue("N(OO)", iter, it->it_callable, it->it_sentinel);
268	0	else
269	0	return Py_BuildValue("N(())", iter);
270	0	}
271
272		static PyMethodDef calliter_methods[] = {
273		{"__reduce__", calliter_reduce, METH_NOARGS, reduce_doc},
274		{NULL, NULL} /* sentinel */
275		};
276
277		PyTypeObject PyCallIter_Type = {
278		PyVarObject_HEAD_INIT(&PyType_Type, 0)
279		"callable_iterator", /* tp_name */
280		sizeof(calliterobject), /* tp_basicsize */
281		0, /* tp_itemsize */
282		/* methods */
283		calliter_dealloc, /* tp_dealloc */
284		0, /* tp_vectorcall_offset */
285		0, /* tp_getattr */
286		0, /* tp_setattr */
287		0, /* tp_as_async */
288		0, /* tp_repr */
289		0, /* tp_as_number */
290		0, /* tp_as_sequence */
291		0, /* tp_as_mapping */
292		0, /* tp_hash */
293		0, /* tp_call */
294		0, /* tp_str */
295		PyObject_GenericGetAttr, /* tp_getattro */
296		0, /* tp_setattro */
297		0, /* tp_as_buffer */
298		Py_TPFLAGS_DEFAULT \| Py_TPFLAGS_HAVE_GC, /* tp_flags */
299		0, /* tp_doc */
300		calliter_traverse, /* tp_traverse */
301		0, /* tp_clear */
302		0, /* tp_richcompare */
303		0, /* tp_weaklistoffset */
304		PyObject_SelfIter, /* tp_iter */
305		calliter_iternext, /* tp_iternext */
306		calliter_methods, /* tp_methods */
307		};
308
309
310		/* -------------------------------------- */
311
312		typedef struct {
313		PyObject_HEAD
314		PyObject *wrapped;
315		PyObject *default_value;
316		} anextawaitableobject;
317
318	0	#define anextawaitableobject_CAST(op) ((anextawaitableobject *)(op))
319
320		static void
321		anextawaitable_dealloc(PyObject *op)
322	0	{
323	0	anextawaitableobject *obj = anextawaitableobject_CAST(op);
324	0	_PyObject_GC_UNTRACK(obj);
325	0	Py_XDECREF(obj->wrapped);
326	0	Py_XDECREF(obj->default_value);
327	0	PyObject_GC_Del(obj);
328	0	}
329
330		static int
331		anextawaitable_traverse(PyObject op, visitproc visit, void arg)
332	0	{
333	0	anextawaitableobject *obj = anextawaitableobject_CAST(op);
334	0	Py_VISIT(obj->wrapped);
335	0	Py_VISIT(obj->default_value);
336	0	return 0;
337	0	}
338
339		static PyObject *
340		anextawaitable_getiter(anextawaitableobject *obj)
341	0	{
342	0	assert(obj->wrapped != NULL);
343	0	PyObject *awaitable = _PyCoro_GetAwaitableIter(obj->wrapped);
344	0	if (awaitable == NULL) {
345	0	return NULL;
346	0	}
347	0	if (Py_TYPE(awaitable)->tp_iternext == NULL) {
348		/* _PyCoro_GetAwaitableIter returns a Coroutine, a Generator,
349		* or an iterator. Of these, only coroutines lack tp_iternext.
350		*/
351	0	assert(PyCoro_CheckExact(awaitable));
352	0	unaryfunc getter = Py_TYPE(awaitable)->tp_as_async->am_await;
353	0	PyObject *new_awaitable = getter(awaitable);
354	0	if (new_awaitable == NULL) {
355	0	Py_DECREF(awaitable);
356	0	return NULL;
357	0	}
358	0	Py_SETREF(awaitable, new_awaitable);
359	0	if (!PyIter_Check(awaitable)) {
360	0	PyErr_SetString(PyExc_TypeError,
361	0	"__await__ returned a non-iterable");
362	0	Py_DECREF(awaitable);
363	0	return NULL;
364	0	}
365	0	}
366	0	return awaitable;
367	0	}
368
369		static PyObject *
370		anextawaitable_iternext(PyObject *op)
371	0	{
372		/* Consider the following class:
373		*
374		* class A:
375		* async def __anext__(self):
376		* ...
377		* a = A()
378		*
379		* Then `await anext(a)` should call
380		* a.__anext__().__await__().__next__()
381		*
382		* On the other hand, given
383		*
384		* async def agen():
385		* yield 1
386		* yield 2
387		* gen = agen()
388		*
389		* Then `await anext(gen)` can just call
390		* gen.__anext__().__next__()
391		*/
392	0	anextawaitableobject *obj = anextawaitableobject_CAST(op);
393	0	PyObject *awaitable = anextawaitable_getiter(obj);
394	0	if (awaitable == NULL) {
395	0	return NULL;
396	0	}
397	0	PyObject result = (Py_TYPE(awaitable)->tp_iternext)(awaitable);
398	0	Py_DECREF(awaitable);
399	0	if (result != NULL) {
400	0	return result;
401	0	}
402	0	if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration)) {
403	0	PyErr_Clear();
404	0	_PyGen_SetStopIterationValue(obj->default_value);
405	0	}
406	0	return NULL;
407	0	}
408
409
410		static PyObject *
411		anextawaitable_proxy(anextawaitableobject obj, char meth, PyObject *arg)
412	0	{
413	0	PyObject *awaitable = anextawaitable_getiter(obj);
414	0	if (awaitable == NULL) {
415	0	return NULL;
416	0	}
417		// When specified, 'arg' may be a tuple (if coming from a METH_VARARGS
418		// method) or a single object (if coming from a METH_O method).
419	0	PyObject *ret = arg == NULL
420	0	? PyObject_CallMethod(awaitable, meth, NULL)
421	0	: PyObject_CallMethod(awaitable, meth, "O", arg);
422	0	Py_DECREF(awaitable);
423	0	if (ret != NULL) {
424	0	return ret;
425	0	}
426	0	if (PyErr_ExceptionMatches(PyExc_StopAsyncIteration)) {
427		/* `anextawaitableobject` is only used by `anext()` when
428		* a default value is provided. So when we have a StopAsyncIteration
429		* exception we replace it with a `StopIteration(default)`, as if
430		* it was the return value of `__anext__()` coroutine.
431		*/
432	0	PyErr_Clear();
433	0	_PyGen_SetStopIterationValue(obj->default_value);
434	0	}
435	0	return NULL;
436	0	}
437
438
439		static PyObject *
440		anextawaitable_send(PyObject op, PyObject arg)
441	0	{
442	0	anextawaitableobject *obj = anextawaitableobject_CAST(op);
443	0	return anextawaitable_proxy(obj, "send", arg);
444	0	}
445
446
447		static PyObject *
448		anextawaitable_throw(PyObject op, PyObject args)
449	0	{
450	0	anextawaitableobject *obj = anextawaitableobject_CAST(op);
451	0	return anextawaitable_proxy(obj, "throw", args);
452	0	}
453
454
455		static PyObject *
456		anextawaitable_close(PyObject op, PyObject Py_UNUSED(dummy))
457	0	{
458	0	anextawaitableobject *obj = anextawaitableobject_CAST(op);
459	0	return anextawaitable_proxy(obj, "close", NULL);
460	0	}
461
462
463		PyDoc_STRVAR(send_doc,
464		"send(arg) -> send 'arg' into the wrapped iterator,\n\
465		return next yielded value or raise StopIteration.");
466
467
468		PyDoc_STRVAR(throw_doc,
469		"throw(value)\n\
470		throw(typ[,val[,tb]])\n\
471		\n\
472		raise exception in the wrapped iterator, return next yielded value\n\
473		or raise StopIteration.\n\
474		the (type, val, tb) signature is deprecated, \n\
475		and may be removed in a future version of Python.");
476
477
478		PyDoc_STRVAR(close_doc,
479		"close() -> raise GeneratorExit inside generator.");
480
481
482		static PyMethodDef anextawaitable_methods[] = {
483		{"send", anextawaitable_send, METH_O, send_doc},
484		{"throw", anextawaitable_throw, METH_VARARGS, throw_doc},
485		{"close", anextawaitable_close, METH_NOARGS, close_doc},
486		{NULL, NULL} /* Sentinel */
487		};
488
489
490		static PyAsyncMethods anextawaitable_as_async = {
491		PyObject_SelfIter, /* am_await */
492		0, /* am_aiter */
493		0, /* am_anext */
494		0, /* am_send */
495		};
496
497		PyTypeObject _PyAnextAwaitable_Type = {
498		PyVarObject_HEAD_INIT(&PyType_Type, 0)
499		"anext_awaitable", /* tp_name */
500		sizeof(anextawaitableobject), /* tp_basicsize */
501		0, /* tp_itemsize */
502		/* methods */
503		anextawaitable_dealloc, /* tp_dealloc */
504		0, /* tp_vectorcall_offset */
505		0, /* tp_getattr */
506		0, /* tp_setattr */
507		&anextawaitable_as_async, /* tp_as_async */
508		0, /* tp_repr */
509		0, /* tp_as_number */
510		0, /* tp_as_sequence */
511		0, /* tp_as_mapping */
512		0, /* tp_hash */
513		0, /* tp_call */
514		0, /* tp_str */
515		PyObject_GenericGetAttr, /* tp_getattro */
516		0, /* tp_setattro */
517		0, /* tp_as_buffer */
518		Py_TPFLAGS_DEFAULT \| Py_TPFLAGS_HAVE_GC, /* tp_flags */
519		0, /* tp_doc */
520		anextawaitable_traverse, /* tp_traverse */
521		0, /* tp_clear */
522		0, /* tp_richcompare */
523		0, /* tp_weaklistoffset */
524		PyObject_SelfIter, /* tp_iter */
525		anextawaitable_iternext, /* tp_iternext */
526		anextawaitable_methods, /* tp_methods */
527		};
528
529		PyObject *
530		PyAnextAwaitable_New(PyObject awaitable, PyObject default_value)
531	0	{
532	0	anextawaitableobject *anext = PyObject_GC_New(
533	0	anextawaitableobject, &_PyAnextAwaitable_Type);
534	0	if (anext == NULL) {
535	0	return NULL;
536	0	}
537	0	anext->wrapped = Py_NewRef(awaitable);
538	0	anext->default_value = Py_NewRef(default_value);
539	0	_PyObject_GC_TRACK(anext);
540	0	return (PyObject *)anext;
541	0	}