[3.12] GH-101588: Deprecate pickle/copy/deepcopy support in itertools (GH-104965) (GH-104997)

1 files changed, 43 insertions, 1 deletions

diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c
index 555eab0..4a6d131 100644
--- a/Modules/itertoolsmodule.c
+++ b/Modules/itertoolsmodule.c
@@ -93,6 +93,16 @@ class itertools.pairwise "pairwiseobject *" "clinic_state()->pairwise_type"
 #undef clinic_state_by_cls
 #undef clinic_state
 
+/* Deprecation of pickle support:  GH-101588 *********************************/
+
+#define ITERTOOL_PICKLE_DEPRECATION                                           \
+    if (PyErr_WarnEx(                                                         \
+            PyExc_DeprecationWarning,                                         \
+            "Itertool pickle/copy/deepcopy support "                          \
+            "will be removed in a Python 3.14.", 1) < 0) {                    \
+        return NULL;                                                          \
+    }
+
 /* batched object ************************************************************/
 
 /* Note:  The built-in zip() function includes a "strict" argument
@@ -506,6 +516,7 @@ groupby_reduce(groupbyobject *lz, PyObject *Py_UNUSED(ignored))
     /* reduce as a 'new' call with an optional 'setstate' if groupby
      * has started
      */
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *value;
     if (lz->tgtkey && lz->currkey && lz->currvalue)
         value = Py_BuildValue("O(OO)(OOO)", Py_TYPE(lz),
@@ -522,6 +533,7 @@ PyDoc_STRVAR(reduce_doc, "Return state information for pickling.");
 static PyObject *
 groupby_setstate(groupbyobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *currkey, *currvalue, *tgtkey;
     if (!PyTuple_Check(state)) {
         PyErr_SetString(PyExc_TypeError, "state is not a tuple");
@@ -660,6 +672,7 @@ _grouper_next(_grouperobject *igo)
 static PyObject *
 _grouper_reduce(_grouperobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (((groupbyobject *)lz->parent)->currgrouper != lz) {
         return Py_BuildValue("N(())", _PyEval_GetBuiltin(&_Py_ID(iter)));
     }
@@ -828,6 +841,7 @@ teedataobject_dealloc(teedataobject *tdo)
 static PyObject *
 teedataobject_reduce(teedataobject *tdo, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     int i;
     /* create a temporary list of already iterated values */
     PyObject *values = PyList_New(tdo->numread);
@@ -1041,12 +1055,14 @@ tee_dealloc(teeobject *to)
 static PyObject *
 tee_reduce(teeobject *to, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     return Py_BuildValue("O(())(Oi)", Py_TYPE(to), to->dataobj, to->index);
 }
 
 static PyObject *
 tee_setstate(teeobject *to, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     teedataobject *tdo;
     int index;
     if (!PyTuple_Check(state)) {
@@ -1275,6 +1291,7 @@ cycle_next(cycleobject *lz)
 static PyObject *
 cycle_reduce(cycleobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     /* Create a new cycle with the iterator tuple, then set the saved state */
     if (lz->it == NULL) {
         PyObject *it = PyObject_GetIter(lz->saved);
@@ -1298,6 +1315,7 @@ cycle_reduce(cycleobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 cycle_setstate(cycleobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *saved=NULL;
     int firstpass;
     if (!PyTuple_Check(state)) {
@@ -1446,12 +1464,14 @@ dropwhile_next(dropwhileobject *lz)
 static PyObject *
 dropwhile_reduce(dropwhileobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     return Py_BuildValue("O(OO)l", Py_TYPE(lz), lz->func, lz->it, lz->start);
 }
 
 static PyObject *
 dropwhile_setstate(dropwhileobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     int start = PyObject_IsTrue(state);
     if (start < 0)
         return NULL;
@@ -1584,12 +1604,14 @@ takewhile_next(takewhileobject *lz)
 static PyObject *
 takewhile_reduce(takewhileobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     return Py_BuildValue("O(OO)l", Py_TYPE(lz), lz->func, lz->it, lz->stop);
 }
 
 static PyObject *
 takewhile_reduce_setstate(takewhileobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     int stop = PyObject_IsTrue(state);
 
     if (stop < 0)
@@ -1786,6 +1808,7 @@ empty:
 static PyObject *
 islice_reduce(isliceobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     /* When unpickled, generate a new object with the same bounds,
      * then 'setstate' with the next and count
      */
@@ -1818,6 +1841,7 @@ islice_reduce(isliceobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 islice_setstate(isliceobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     Py_ssize_t cnt = PyLong_AsSsize_t(state);
 
     if (cnt == -1 && PyErr_Occurred())
@@ -1953,6 +1977,7 @@ starmap_next(starmapobject *lz)
 static PyObject *
 starmap_reduce(starmapobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     /* Just pickle the iterator */
     return Py_BuildValue("O(OO)", Py_TYPE(lz), lz->func, lz->it);
 }
@@ -2109,6 +2134,7 @@ chain_next(chainobject *lz)
 static PyObject *
 chain_reduce(chainobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (lz->source) {
         /* we can't pickle function objects (itertools.from_iterable) so
          * we must use setstate to replace the iterable.  One day we
@@ -2128,6 +2154,7 @@ chain_reduce(chainobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 chain_setstate(chainobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *source, *active=NULL;
 
     if (!PyTuple_Check(state)) {
@@ -2403,6 +2430,7 @@ empty:
 static PyObject *
 product_reduce(productobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (lz->stopped) {
         return Py_BuildValue("O(())", Py_TYPE(lz));
     } else if (lz->result == NULL) {
@@ -2433,6 +2461,7 @@ product_reduce(productobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 product_setstate(productobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *result;
     Py_ssize_t n, i;
 
@@ -2711,6 +2740,7 @@ empty:
 static PyObject *
 combinations_reduce(combinationsobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (lz->result == NULL) {
         return Py_BuildValue("O(On)", Py_TYPE(lz), lz->pool, lz->r);
     } else if (lz->stopped) {
@@ -2740,6 +2770,7 @@ combinations_reduce(combinationsobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 combinations_setstate(combinationsobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *result;
     Py_ssize_t i;
     Py_ssize_t n = PyTuple_GET_SIZE(lz->pool);
@@ -3019,6 +3050,7 @@ empty:
 static PyObject *
 cwr_reduce(cwrobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (lz->result == NULL) {
         return Py_BuildValue("O(On)", Py_TYPE(lz), lz->pool, lz->r);
     } else if (lz->stopped) {
@@ -3047,6 +3079,7 @@ cwr_reduce(cwrobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 cwr_setstate(cwrobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *result;
     Py_ssize_t n, i;
 
@@ -3354,6 +3387,7 @@ empty:
 static PyObject *
 permutations_reduce(permutationsobject *po, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (po->result == NULL) {
         return Py_BuildValue("O(On)", Py_TYPE(po), po->pool, po->r);
     } else if (po->stopped) {
@@ -3396,6 +3430,7 @@ permutations_reduce(permutationsobject *po, PyObject *Py_UNUSED(ignored))
 static PyObject *
 permutations_setstate(permutationsobject *po, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     PyObject *indices, *cycles, *result;
     Py_ssize_t n, i;
 
@@ -3593,6 +3628,7 @@ accumulate_next(accumulateobject *lz)
 static PyObject *
 accumulate_reduce(accumulateobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     itertools_state *state = lz->state;
 
     if (lz->initial != Py_None) {
@@ -3628,6 +3664,7 @@ accumulate_reduce(accumulateobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 accumulate_setstate(accumulateobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     Py_INCREF(state);
     Py_XSETREF(lz->total, state);
     Py_RETURN_NONE;
@@ -3776,6 +3813,7 @@ compress_next(compressobject *lz)
 static PyObject *
 compress_reduce(compressobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     return Py_BuildValue("O(OO)", Py_TYPE(lz),
         lz->data, lz->selectors);
 }
@@ -3908,6 +3946,7 @@ filterfalse_next(filterfalseobject *lz)
 static PyObject *
 filterfalse_reduce(filterfalseobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     return Py_BuildValue("O(OO)", Py_TYPE(lz), lz->func, lz->it);
 }
 
@@ -4135,6 +4174,7 @@ count_repr(countobject *lz)
 static PyObject *
 count_reduce(countobject *lz, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     if (lz->cnt == PY_SSIZE_T_MAX)
         return Py_BuildValue("O(OO)", Py_TYPE(lz), lz->long_cnt, lz->long_step);
     return Py_BuildValue("O(n)", Py_TYPE(lz), lz->cnt);
@@ -4258,6 +4298,7 @@ PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(
 static PyObject *
 repeat_reduce(repeatobject *ro, PyObject *Py_UNUSED(ignored))
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     /* unpickle this so that a new repeat iterator is constructed with an
      * object, then call __setstate__ on it to set cnt
      */
@@ -4478,7 +4519,7 @@ zip_longest_next(ziplongestobject *lz)
 static PyObject *
 zip_longest_reduce(ziplongestobject *lz, PyObject *Py_UNUSED(ignored))
 {
-
+    ITERTOOL_PICKLE_DEPRECATION;
     /* Create a new tuple with empty sequences where appropriate to pickle.
      * Then use setstate to set the fillvalue
      */
@@ -4505,6 +4546,7 @@ zip_longest_reduce(ziplongestobject *lz, PyObject *Py_UNUSED(ignored))
 static PyObject *
 zip_longest_setstate(ziplongestobject *lz, PyObject *state)
 {
+    ITERTOOL_PICKLE_DEPRECATION;
     Py_INCREF(state);
     Py_XSETREF(lz->fillvalue, state);
     Py_RETURN_NONE;