diff options
Diffstat (limited to 'Modules/_collectionsmodule.c')
| -rw-r--r-- | Modules/_collectionsmodule.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c index dbe44e1455..3e2c69fd63 100644 --- a/Modules/_collectionsmodule.c +++ b/Modules/_collectionsmodule.c @@ -1211,6 +1211,7 @@ deque_traverse(dequeobject *deque, visitproc visit, void *arg) static PyObject * deque_copy(PyObject *deque) { + dequeobject *old_deque = (dequeobject *)deque; if (Py_TYPE(deque) == &deque_type) { dequeobject *new_deque; PyObject *rv; @@ -1218,8 +1219,14 @@ deque_copy(PyObject *deque) new_deque = (dequeobject *)deque_new(&deque_type, (PyObject *)NULL, (PyObject *)NULL); if (new_deque == NULL) return NULL; - new_deque->maxlen = ((dequeobject *)deque)->maxlen; - rv = deque_extend(new_deque, deque); + new_deque->maxlen = old_deque->maxlen; + /* Fast path for the deque_repeat() common case where len(deque) == 1 */ + if (Py_SIZE(deque) == 1 && new_deque->maxlen != 0) { + PyObject *item = old_deque->leftblock->data[old_deque->leftindex]; + rv = deque_append(new_deque, item); + } else { + rv = deque_extend(new_deque, deque); + } if (rv != NULL) { Py_DECREF(rv); return (PyObject *)new_deque; @@ -1227,11 +1234,11 @@ deque_copy(PyObject *deque) Py_DECREF(new_deque); return NULL; } - if (((dequeobject *)deque)->maxlen == -1) + if (old_deque->maxlen == -1) return PyObject_CallFunction((PyObject *)(Py_TYPE(deque)), "O", deque, NULL); else return PyObject_CallFunction((PyObject *)(Py_TYPE(deque)), "Oi", - deque, ((dequeobject *)deque)->maxlen, NULL); + deque, old_deque->maxlen, NULL); } PyDoc_STRVAR(copy_doc, "Return a shallow copy of a deque."); |