diff --git a/Misc/NEWS b/Misc/NEWS index 30e61117fe3..cd9a2c144fa 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -79,7 +79,8 @@ Library when necessary. Patch by Oscar Benjamin. - Issue #18594: The fast path for collections.Counter() was never taken - due to an over-restrictive type check. + due to an over-restrictive type check. And the fallback path did + not implement the same algorithm as the pure python code. - Properly initialize all fields of a SSL object after allocation. diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c index cb1674898b3..b2446674747 100644 --- a/Modules/_collectionsmodule.c +++ b/Modules/_collectionsmodule.c @@ -1694,7 +1694,9 @@ _count_elements(PyObject *self, PyObject *args) PyObject *it, *iterable, *mapping, *oldval; PyObject *newval = NULL; PyObject *key = NULL; + PyObject *zero = NULL; PyObject *one = NULL; + PyObject *mapping_get = NULL; PyObject *mapping_getitem; PyObject *mapping_setitem; PyObject *dict_getitem; @@ -1708,10 +1710,8 @@ _count_elements(PyObject *self, PyObject *args) return NULL; one = PyLong_FromLong(1); - if (one == NULL) { - Py_DECREF(it); - return NULL; - } + if (one == NULL) + goto done; mapping_getitem = _PyType_LookupId(Py_TYPE(mapping), &PyId___getitem__); dict_getitem = _PyType_LookupId(&PyDict_Type, &PyId___getitem__); @@ -1741,23 +1741,25 @@ _count_elements(PyObject *self, PyObject *args) Py_DECREF(key); } } else { + mapping_get = PyObject_GetAttrString(mapping, "get"); + if (mapping_get == NULL) + goto done; + + zero = PyLong_FromLong(0); + if (zero == NULL) + goto done; + while (1) { key = PyIter_Next(it); if (key == NULL) break; - oldval = PyObject_GetItem(mapping, key); - if (oldval == NULL) { - if (!PyErr_Occurred() || !PyErr_ExceptionMatches(PyExc_KeyError)) - break; - PyErr_Clear(); - Py_INCREF(one); - newval = one; - } else { - newval = PyNumber_Add(oldval, one); - Py_DECREF(oldval); - if (newval == NULL) - break; - } + oldval = PyObject_CallFunctionObjArgs(mapping_get, key, zero, NULL); + if (oldval == NULL) + break; + newval = PyNumber_Add(oldval, one); + Py_DECREF(oldval); + if (newval == NULL) + break; if (PyObject_SetItem(mapping, key, newval) == -1) break; Py_CLEAR(newval); @@ -1765,10 +1767,13 @@ _count_elements(PyObject *self, PyObject *args) } } +done: Py_DECREF(it); Py_XDECREF(key); Py_XDECREF(newval); - Py_DECREF(one); + Py_XDECREF(mapping_get); + Py_XDECREF(zero); + Py_XDECREF(one); if (PyErr_Occurred()) return NULL; Py_RETURN_NONE;