diff options
Diffstat (limited to 'Objects/dictobject.c')
| -rw-r--r-- | Objects/dictobject.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/Objects/dictobject.c b/Objects/dictobject.c index ce4c578..73c459f 100644 --- a/Objects/dictobject.c +++ b/Objects/dictobject.c @@ -999,9 +999,19 @@ dict_update(PyObject *mp, PyObject *args) return Py_None; } +/* Update unconditionally replaces existing items. + Merge has a 3rd argument 'override'; if set, it acts like Update, + otherwise it leaves existing items unchanged. */ + int PyDict_Update(PyObject *a, PyObject *b) { + return PyDict_Merge(a, b, 1); +} + +int +PyDict_Merge(PyObject *a, PyObject *b, int override) +{ register PyDictObject *mp, *other; register int i; dictentry *entry; @@ -1031,7 +1041,9 @@ PyDict_Update(PyObject *a, PyObject *b) } for (i = 0; i <= other->ma_mask; i++) { entry = &other->ma_table[i]; - if (entry->me_value != NULL) { + if (entry->me_value != NULL && + (override || + PyDict_GetItem(a, entry->me_key) == NULL)) { Py_INCREF(entry->me_key); Py_INCREF(entry->me_value); insertdict(mp, entry->me_key, entry->me_hash, @@ -1060,13 +1072,17 @@ PyDict_Update(PyObject *a, PyObject *b) return -1; for (key = PyIter_Next(iter); key; key = PyIter_Next(iter)) { + if (!override && PyDict_GetItem(a, key) != NULL) { + Py_DECREF(key); + continue; + } value = PyObject_GetItem(b, key); if (value == NULL) { Py_DECREF(iter); Py_DECREF(key); return -1; } - status = PyDict_SetItem((PyObject*)mp, key, value); + status = PyDict_SetItem(a, key, value); Py_DECREF(key); Py_DECREF(value); if (status < 0) { |