py: Make mp_map_lookup not allocate memory on removal.
diff --git a/py/map.c b/py/map.c
index 5b9e803..bb3d5d8 100644
--- a/py/map.c
+++ b/py/map.c
@@ -91,6 +91,12 @@
m_del(mp_map_elem_t, old_table, old_alloc);
}
+// MP_MAP_LOOKUP behaviour:
+// - returns NULL if not found, else the slot it was found in with key,value non-null
+// MP_MAP_LOOKUP_ADD_IF_NOT_FOUND behaviour:
+// - returns slot, with key non-null and value=MP_OBJ_NULL if it was added
+// MP_MAP_LOOKUP_REMOVE_IF_FOUND behaviour:
+// - returns NULL if not found, else the slot if was found in with key null and value non-null
mp_map_elem_t* mp_map_lookup(mp_map_t *map, mp_obj_t index, mp_map_lookup_kind_t lookup_kind) {
// if the map is a fixed array then we must do a brute force linear search
if (map->table_is_fixed_array) {
@@ -135,7 +141,7 @@
}
return slot;
} else {
- return MP_OBJ_NULL;
+ return NULL;
}
} else if (slot->key == MP_OBJ_SENTINEL) {
// found deleted slot, remember for later
@@ -146,10 +152,6 @@
// found index
// Note: CPython does not replace the index; try x={True:'true'};x[1]='one';x
if (lookup_kind & MP_MAP_LOOKUP_REMOVE_IF_FOUND) {
- // this leaks this memory (but see dict_get_helper)
- mp_map_elem_t *retval = m_new(mp_map_elem_t, 1);
- retval->key = slot->key;
- retval->value = slot->value;
// delete element in this slot
map->used--;
if (map->table[(pos + 1) % map->alloc].key == MP_OBJ_NULL) {
@@ -158,7 +160,7 @@
} else {
slot->key = MP_OBJ_SENTINEL;
}
- return retval;
+ // keep slot->value so that caller can access it if needed
}
return slot;
}
@@ -185,7 +187,7 @@
start_pos = pos = hash % map->alloc;
}
} else {
- return MP_OBJ_NULL;
+ return NULL;
}
}
}