/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: 2025-07-04 06:49

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	591	{
20	591	seqiterobject *it;
21
22	591	if (!PySequence_Check(seq)) {
23	0	PyErr_BadInternalCall();
24	0	return NULL;
25	0	}
26	591	it = PyObject_GC_New(seqiterobject, &PySeqIter_Type);
27	591	if (it == NULL)
28	0	return NULL;
29	591	it->it_index = 0;
30	591	it->it_seq = Py_NewRef(seq);
31	591	_PyObject_GC_TRACK(it);
32	591	return (PyObject *)it;
33	591	}
34
35		static void
36		iter_dealloc(PyObject *op)
37	591	{
38	591	seqiterobject it = (seqiterobject)op;
39	591	_PyObject_GC_UNTRACK(it);
40	591	Py_XDECREF(it->it_seq);
41	591	PyObject_GC_Del(it);
42	591	}
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	1.37k	{
55	1.37k	seqiterobject *it;
56	1.37k	PyObject *seq;
57	1.37k	PyObject *result;
58
59	1.37k	assert(PySeqIter_Check(iterator));
60	1.37k	it = (seqiterobject *)iterator;
61	1.37k	seq = it->it_seq;
62	1.37k	if (seq == NULL)
63	0	return NULL;
64	1.37k	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	1.37k	result = PySequence_GetItem(seq, it->it_index);
71	1.37k	if (result != NULL) {
72	783	it->it_index++;
73	783	return result;
74	783	}
75	591	if (PyErr_ExceptionMatches(PyExc_IndexError) \|\|
76	591	PyErr_ExceptionMatches(PyExc_StopIteration))
77	591	{
78	591	PyErr_Clear();
79	591	it->it_seq = NULL;
80	591	Py_DECREF(seq);
81	591	}
82	591	return NULL;
83	1.37k	}
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	338k	{
195	338k	calliterobject *it;
196	338k	it = PyObject_GC_New(calliterobject, &PyCallIter_Type);
197	338k	if (it == NULL)
198	0	return NULL;
199	338k	it->it_callable = Py_NewRef(callable);
200	338k	it->it_sentinel = Py_NewRef(sentinel);
201	338k	_PyObject_GC_TRACK(it);
202	338k	return (PyObject *)it;
203	338k	}
204		static void
205		calliter_dealloc(PyObject *op)
206	338k	{
207	338k	calliterobject it = (calliterobject)op;
208	338k	_PyObject_GC_UNTRACK(it);
209	338k	Py_XDECREF(it->it_callable);
210	338k	Py_XDECREF(it->it_sentinel);
211	338k	PyObject_GC_Del(it);
212	338k	}
213
214		static int
215		calliter_traverse(PyObject op, visitproc visit, void arg)
216	373	{
217	373	calliterobject it = (calliterobject)op;
218	373	Py_VISIT(it->it_callable);
219	373	Py_VISIT(it->it_sentinel);
220	373	return 0;
221	373	}
222
223		static PyObject *
224		calliter_iternext(PyObject *op)
225	2.73M	{
226	2.73M	calliterobject it = (calliterobject)op;
227	2.73M	PyObject *result;
228
229	2.73M	if (it->it_callable == NULL) {
230	0	return NULL;
231	0	}
232
233	2.73M	result = _PyObject_CallNoArgs(it->it_callable);
234	2.73M	if (result != NULL && it->it_sentinel != NULL){
235	2.73M	int ok;
236
237	2.73M	ok = PyObject_RichCompareBool(it->it_sentinel, result, Py_EQ);
238	2.73M	if (ok == 0) {
239	2.39M	return result; /* Common case, fast path */
240	2.39M	}
241
242	338k	if (ok > 0) {
243	338k	Py_CLEAR(it->it_callable);
244	338k	Py_CLEAR(it->it_sentinel);
245	338k	}
246	338k	}
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	338k	Py_XDECREF(result);
253	338k	return NULL;
254	2.73M	}
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	}