py: memoryview: implement memoryview.cast if CPYTHON_COMPAT

This commit is contained in:
Jeff Epler 2021-02-20 10:35:27 -06:00
parent 5d154937d6
commit 646eb9a7db

View File

@ -238,6 +238,24 @@ STATIC mp_obj_t memoryview_make_new(const mp_obj_type_t *type_in, size_t n_args,
return MP_OBJ_FROM_PTR(self);
}
STATIC mp_obj_t memoryview_cast(const mp_obj_t self_in, const mp_obj_t typecode_in) {
mp_obj_array_t *self = MP_OBJ_TO_PTR(self_in);
const char *typecode = mp_obj_str_get_str(typecode_in);
size_t element_size = mp_binary_get_size('@', typecode[0], NULL);
size_t bytelen = self->len * mp_binary_get_size('@', self->typecode & ~MP_OBJ_ARRAY_TYPECODE_FLAG_RW, NULL);
if (bytelen % element_size != 0) {
mp_raise_TypeError(translate("memoryview: length is not a multiple of itemsize"));
}
mp_obj_array_t *result = MP_OBJ_TO_PTR(mp_obj_new_memoryview(*typecode, bytelen / element_size, self->items));
// test if the object can be written to
if (self->typecode & MP_OBJ_ARRAY_TYPECODE_FLAG_RW) {
result->typecode |= MP_OBJ_ARRAY_TYPECODE_FLAG_RW; // indicate writable buffer
}
return MP_OBJ_FROM_PTR(result);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(memoryview_cast_obj, memoryview_cast);
#endif
STATIC mp_obj_t array_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
@ -691,6 +709,15 @@ const mp_obj_type_t mp_type_bytearray = {
#endif
#if MICROPY_PY_BUILTINS_MEMORYVIEW
#if MICROPY_CPYTHON_COMPAT
STATIC const mp_rom_map_elem_t memoryview_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_cast), MP_ROM_PTR(&memoryview_cast_obj) },
};
STATIC MP_DEFINE_CONST_DICT(memoryview_locals_dict, memoryview_locals_dict_table);
#endif
const mp_obj_type_t mp_type_memoryview = {
{ &mp_type_type },
.name = MP_QSTR_memoryview,
@ -700,6 +727,9 @@ const mp_obj_type_t mp_type_memoryview = {
.binary_op = array_binary_op,
.subscr = array_subscr,
.buffer_p = { .get_buffer = array_get_buffer },
#if MICROPY_CPYTHON_COMPAT
.locals_dict = (mp_obj_dict_t*)&memoryview_locals_dict,
#endif
};
#endif