/* Shared helper to implement ES6 Object.setPrototypeOf and
* Object.prototype.__proto__ setter.
*
* https://people.mozilla.org/~jorendorff/es6-draft.html#sec-get-object.prototype.__proto__
* https://people.mozilla.org/~jorendorff/es6-draft.html#sec-object.setprototypeof
*/
duk_ret_t duk_bi_object_setprototype_shared(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *h_obj;
duk_hobject *h_new_proto;
duk_hobject *h_curr;
duk_ret_t ret_success = 1; /* retval for success path */
/* Preliminaries for __proto__ and setPrototypeOf (E6 19.1.2.18 steps 1-4);
* magic: 0=setter call, 1=Object.setPrototypeOf
*/
if (duk_get_current_magic(ctx) == 0) {
duk_push_this_check_object_coercible(ctx);
duk_insert(ctx, 0);
if (!duk_check_type_mask(ctx, 1, DUK_TYPE_MASK_NULL | DUK_TYPE_MASK_OBJECT)) {
return 0;
}
/* __proto__ setter returns 'undefined' on success unlike the
* setPrototypeOf() call which returns the target object.
*/
ret_success = 0;
} else {
duk_require_object_coercible(ctx, 0);
duk_require_type_mask(ctx, 1, DUK_TYPE_MASK_NULL | DUK_TYPE_MASK_OBJECT);
}
h_obj = duk_get_hobject(ctx, 0);
if (!h_obj) {
goto skip;
}
h_new_proto = duk_get_hobject(ctx, 1);
DUK_ASSERT(h_obj != NULL);
/* h_new_proto may be NULL */
/* [[SetPrototypeOf]] standard behavior, E6 9.1.2 */
/* NOTE: steps 7-8 seem to be a cut-paste bug in the E6 draft */
/* TODO: implement Proxy object support here */
if (h_new_proto == h_obj->prototype) {
goto skip;
}
if (!DUK_HOBJECT_HAS_EXTENSIBLE(h_obj)) {
goto fail_nonextensible;
}
for (h_curr = h_new_proto; h_curr != NULL; h_curr = h_curr->prototype) {
/* Loop prevention */
if (h_curr == h_obj) {
goto fail_loop;
}
}
DUK_HOBJECT_SET_PROTOTYPE_UPDREF(thr, h_obj, h_new_proto);
/* fall thru */
skip:
duk_set_top(ctx, 1);
return ret_success;
fail_nonextensible:
fail_loop:
return DUK_RET_TYPE_ERROR;
}
/* Shared helper to implement ES2015 Object.setPrototypeOf,
* Object.prototype.__proto__ setter, and Reflect.setPrototypeOf.
*
* http://www.ecma-international.org/ecma-262/6.0/index.html#sec-get-object.prototype.__proto__
* http://www.ecma-international.org/ecma-262/6.0/index.html#sec-object.setprototypeof
*/
DUK_INTERNAL duk_ret_t duk_bi_object_setprototype_shared(duk_hthread *thr) {
/*
* magic = 0: __proto__ setter
* magic = 1: Object.setPrototypeOf()
* magic = 2: Reflect.setPrototypeOf()
*/
duk_hobject *h_obj;
duk_hobject *h_new_proto;
duk_hobject *h_curr;
duk_ret_t ret_success = 1; /* retval for success path */
duk_uint_t mask;
duk_int_t magic;
/* Preliminaries for __proto__ and setPrototypeOf (E6 19.1.2.18 steps 1-4). */
magic = duk_get_current_magic(thr);
if (magic == 0) {
duk_push_this_check_object_coercible(thr);
duk_insert(thr, 0);
if (!duk_check_type_mask(thr, 1, DUK_TYPE_MASK_NULL | DUK_TYPE_MASK_OBJECT)) {
return 0;
}
/* __proto__ setter returns 'undefined' on success unlike the
* setPrototypeOf() call which returns the target object.
*/
ret_success = 0;
} else {
if (magic == 1) {
duk_require_object_coercible(thr, 0);
} else {
duk_require_hobject_accept_mask(thr, 0,
DUK_TYPE_MASK_LIGHTFUNC |
DUK_TYPE_MASK_BUFFER);
}
duk_require_type_mask(thr, 1, DUK_TYPE_MASK_NULL | DUK_TYPE_MASK_OBJECT);
}
h_new_proto = duk_get_hobject(thr, 1);
/* h_new_proto may be NULL */
mask = duk_get_type_mask(thr, 0);
if (mask & (DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER)) {
duk_hobject *curr_proto;
curr_proto = thr->builtins[(mask & DUK_TYPE_MASK_LIGHTFUNC) ?
DUK_BIDX_FUNCTION_PROTOTYPE :
DUK_BIDX_UINT8ARRAY_PROTOTYPE];
if (h_new_proto == curr_proto) {
goto skip;
}
goto fail_nonextensible;
}
h_obj = duk_get_hobject(thr, 0);
if (h_obj == NULL) {
goto skip;
}
DUK_ASSERT(h_obj != NULL);
/* [[SetPrototypeOf]] standard behavior, E6 9.1.2. */
/* TODO: implement Proxy object support here */
if (h_new_proto == DUK_HOBJECT_GET_PROTOTYPE(thr->heap, h_obj)) {
goto skip;
}
if (!DUK_HOBJECT_HAS_EXTENSIBLE(h_obj)) {
goto fail_nonextensible;
}
for (h_curr = h_new_proto; h_curr != NULL; h_curr = DUK_HOBJECT_GET_PROTOTYPE(thr->heap, h_curr)) {
/* Loop prevention. */
if (h_curr == h_obj) {
goto fail_loop;
}
}
DUK_HOBJECT_SET_PROTOTYPE_UPDREF(thr, h_obj, h_new_proto);
/* fall thru */
skip:
duk_set_top(thr, 1);
if (magic == 2) {
duk_push_true(thr);
}
return ret_success;
fail_nonextensible:
fail_loop:
if (magic != 2) {
DUK_DCERROR_TYPE_INVALID_ARGS(thr);
} else {
duk_push_false(thr);
return 1;
}
}
