py/objdict: Fix optimisation for allocating result in fromkeys.

Iterables don't respond to __len__, so call __len__ on the original
argument.
This commit is contained in:
Damien George 2016-10-17 11:58:57 +11:00
parent e9404e5f5f
commit a3edeb9ea5

View File

@ -250,15 +250,16 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(dict_copy_obj, dict_copy);
// this is a classmethod
STATIC mp_obj_t dict_fromkeys(size_t n_args, const mp_obj_t *args) {
mp_obj_t iter = mp_getiter(args[1]);
mp_obj_t len = mp_obj_len_maybe(iter);
mp_obj_t value = mp_const_none;
mp_obj_t next = MP_OBJ_NULL;
mp_obj_t self_out;
if (n_args > 2) {
value = args[2];
}
// optimisation to allocate result based on len of argument
mp_obj_t self_out;
mp_obj_t len = mp_obj_len_maybe(args[1]);
if (len == MP_OBJ_NULL) {
/* object's type doesn't have a __len__ slot */
self_out = mp_obj_new_dict(0);