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/*
* Object built-ins
*/
#include "duk_internal.h"
DUK_INTERNAL duk_ret_t duk_bi_object_constructor(duk_context *ctx) {
duk_uint_t arg_mask;
arg_mask = duk_get_type_mask(ctx, 0);
if (!duk_is_constructor_call(ctx) && /* not a constructor call */
((arg_mask & (DUK_TYPE_MASK_NULL | DUK_TYPE_MASK_UNDEFINED)) == 0)) { /* and argument not null or undefined */
duk_to_object(ctx, 0);
return 1;
}
/* Pointer and buffer primitive values are treated like other
* primitives values which have a fully fledged object counterpart:
* promote to an object value. Lightfuncs and plain buffers are
* coerced with ToObject() even they could also be returned as is.
*/
if (arg_mask & (DUK_TYPE_MASK_OBJECT |
DUK_TYPE_MASK_STRING |
DUK_TYPE_MASK_BOOLEAN |
DUK_TYPE_MASK_NUMBER |
DUK_TYPE_MASK_POINTER |
DUK_TYPE_MASK_BUFFER |
DUK_TYPE_MASK_LIGHTFUNC)) {
/* For DUK_TYPE_OBJECT the coercion is a no-op and could
* be checked for explicitly, but Object(obj) calls are
* not very common so opt for minimal footprint.
*/
duk_to_object(ctx, 0);
return 1;
}
duk_push_object_helper(ctx,
DUK_HOBJECT_FLAG_EXTENSIBLE |
DUK_HOBJECT_CLASS_AS_FLAGS(DUK_HOBJECT_CLASS_OBJECT),
DUK_BIDX_OBJECT_PROTOTYPE);
return 1;
}
/* Shared helper to implement Object.getPrototypeOf and the ES6
* Object.prototype.__proto__ getter.
*
* http://www.ecma-international.org/ecma-262/6.0/index.html#sec-get-object.prototype.__proto__
*/
DUK_INTERNAL duk_ret_t duk_bi_object_getprototype_shared(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *h;
duk_hobject *proto;
duk_tval *tv;
DUK_UNREF(thr);
/* magic: 0=getter call, 1=Object.getPrototypeOf */
if (duk_get_current_magic(ctx) == 0) {
tv = DUK_HTHREAD_THIS_PTR(thr);
} else {
DUK_ASSERT(duk_get_top(ctx) >= 1);
tv = DUK_GET_TVAL_POSIDX(ctx, 0);
}
switch (DUK_TVAL_GET_TAG(tv)) {
case DUK_TAG_BUFFER:
#if defined(DUK_USE_BUFFEROBJECT_SUPPORT)
proto = thr->builtins[DUK_BIDX_ARRAYBUFFER_PROTOTYPE];
#else
proto = thr->builtins[DUK_BIDX_OBJECT_PROTOTYPE];
#endif
break;
case DUK_TAG_LIGHTFUNC:
proto = thr->builtins[DUK_BIDX_FUNCTION_PROTOTYPE];
break;
case DUK_TAG_OBJECT:
h = DUK_TVAL_GET_OBJECT(tv);
proto = DUK_HOBJECT_GET_PROTOTYPE(thr->heap, h);
break;
default:
/* This implicitly handles CheckObjectCoercible() caused
* TypeError.
*/
return DUK_RET_TYPE_ERROR;
}
if (proto != NULL) {
duk_push_hobject(ctx, proto);
} else {
duk_push_null(ctx);
}
return 1;
}
/* Shared helper to implement ES6 Object.setPrototypeOf and
* Object.prototype.__proto__ setter.
*
* 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_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 */
duk_uint_t mask;
/* 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_new_proto = duk_get_hobject(ctx, 1);
/* h_new_proto may be NULL */
mask = duk_get_type_mask(ctx, 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 :
#if defined(DUK_USE_BUFFEROBJECT_SUPPORT)
DUK_BIDX_ARRAYBUFFER_PROTOTYPE
#else
DUK_BIDX_OBJECT_PROTOTYPE
#endif
];
if (h_new_proto == curr_proto) {
goto skip;
}
goto fail_nonextensible;
}
h_obj = duk_get_hobject(ctx, 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(ctx, 1);
return ret_success;
fail_nonextensible:
fail_loop:
return DUK_RET_TYPE_ERROR;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_get_own_property_descriptor(duk_context *ctx) {
/* XXX: no need for indirect call */
return duk_hobject_object_get_own_property_descriptor(ctx);
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_create(duk_context *ctx) {
duk_tval *tv;
duk_hobject *proto = NULL;
DUK_ASSERT_TOP(ctx, 2);
#if defined(DUK_USE_BUFFEROBJECT_SUPPORT)
duk_hbufobj_promote_plain(ctx, 0);
#endif
tv = duk_get_tval(ctx, 0);
DUK_ASSERT(tv != NULL);
if (DUK_TVAL_IS_NULL(tv)) {
DUK_ASSERT(proto == NULL);
} else if (DUK_TVAL_IS_OBJECT(tv)) {
proto = DUK_TVAL_GET_OBJECT(tv);
DUK_ASSERT(proto != NULL);
} else {
return DUK_RET_TYPE_ERROR;
}
(void) duk_push_object_helper_proto(ctx,
DUK_HOBJECT_FLAG_EXTENSIBLE |
DUK_HOBJECT_CLASS_AS_FLAGS(DUK_HOBJECT_CLASS_OBJECT),
proto);
if (!duk_is_undefined(ctx, 1)) {
/* [ O Properties obj ] */
duk_replace(ctx, 0);
/* [ obj Properties ] */
/* Just call the "original" Object.defineProperties() to
* finish up.
*/
return duk_bi_object_constructor_define_properties(ctx);
}
/* [ O Properties obj ] */
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_define_property(duk_context *ctx) {
duk_hobject *obj;
duk_hstring *key;
duk_hobject *get;
duk_hobject *set;
duk_idx_t idx_value;
duk_uint_t defprop_flags;
DUK_ASSERT(ctx != NULL);
DUK_DDD(DUK_DDDPRINT("Object.defineProperty(): ctx=%p obj=%!T key=%!T desc=%!T",
(void *) ctx,
(duk_tval *) duk_get_tval(ctx, 0),
(duk_tval *) duk_get_tval(ctx, 1),
(duk_tval *) duk_get_tval(ctx, 2)));
/* [ obj key desc ] */
/* Lightfuncs are currently supported by coercing to a temporary
* Function object; changes will be allowed (the coerced value is
* extensible) but will be lost. Same for plain buffers.
*/
obj = duk_require_hobject_promote_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
DUK_ASSERT(obj != NULL);
(void) duk_to_string(ctx, 1);
key = duk_require_hstring(ctx, 1);
(void) duk_require_hobject(ctx, 2);
DUK_ASSERT(obj != NULL);
DUK_ASSERT(key != NULL);
DUK_ASSERT(duk_get_hobject(ctx, 2) != NULL);
/*
* Validate and convert argument property descriptor (an Ecmascript
* object) into a set of defprop_flags and possibly property value,
* getter, and/or setter values on the value stack.
*
* Lightfunc set/get values are coerced to full Functions.
*/
duk_hobject_prepare_property_descriptor(ctx,
2 /*idx_desc*/,
&defprop_flags,
&idx_value,
&get,
&set);
/*
* Use Object.defineProperty() helper for the actual operation.
*/
duk_hobject_define_property_helper(ctx,
defprop_flags,
obj,
key,
idx_value,
get,
set);
/* Ignore the normalize/validate helper outputs on the value stack,
* they're popped automatically.
*/
/*
* Return target object.
*/
duk_push_hobject(ctx, obj);
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_define_properties(duk_context *ctx) {
duk_small_uint_t pass;
duk_uint_t defprop_flags;
duk_hobject *obj;
duk_idx_t idx_value;
duk_hobject *get;
duk_hobject *set;
/* Lightfunc and plain buffer handling by ToObject() coercion. */
obj = duk_require_hobject_promote_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
DUK_ASSERT(obj != NULL);
duk_to_object(ctx, 1); /* properties object */
DUK_DDD(DUK_DDDPRINT("target=%!iT, properties=%!iT",
(duk_tval *) duk_get_tval(ctx, 0),
(duk_tval *) duk_get_tval(ctx, 1)));
/*
* Two pass approach to processing the property descriptors.
* On first pass validate and normalize all descriptors before
* any changes are made to the target object. On second pass
* make the actual modifications to the target object.
*
* Right now we'll just use the same normalize/validate helper
* on both passes, ignoring its outputs on the first pass.
*/
for (pass = 0; pass < 2; pass++) {
duk_set_top(ctx, 2); /* -> [ hobject props ] */
duk_enum(ctx, 1, DUK_ENUM_OWN_PROPERTIES_ONLY /*enum_flags*/);
for (;;) {
duk_hstring *key;
/* [ hobject props enum(props) ] */
duk_set_top(ctx, 3);
if (!duk_next(ctx, 2, 1 /*get_value*/)) {
break;
}
DUK_DDD(DUK_DDDPRINT("-> key=%!iT, desc=%!iT",
(duk_tval *) duk_get_tval(ctx, -2),
(duk_tval *) duk_get_tval(ctx, -1)));
/* [ hobject props enum(props) key desc ] */
duk_hobject_prepare_property_descriptor(ctx,
4 /*idx_desc*/,
&defprop_flags,
&idx_value,
&get,
&set);
/* [ hobject props enum(props) key desc value? getter? setter? ] */
if (pass == 0) {
continue;
}
key = duk_get_hstring(ctx, 3);
DUK_ASSERT(key != NULL);
duk_hobject_define_property_helper(ctx,
defprop_flags,
obj,
key,
idx_value,
get,
set);
}
}
/*
* Return target object
*/
duk_dup_0(ctx);
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_seal_freeze_shared(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *h;
duk_bool_t is_freeze;
is_freeze = (duk_bool_t) duk_get_current_magic(ctx);
if (duk_is_buffer(ctx, 0)) {
/* Plain buffer: already sealed, but not frozen (and can't be frozen
* because index properties can't be made non-writable.
*/
if (is_freeze) {
goto fail_cannot_freeze;
}
return 1;
} else if (duk_is_lightfunc(ctx, 0)) {
/* Lightfunc: already sealed and frozen, success. */
return 1;
}
#if 0
/* Seal/freeze are quite rare in practice so it'd be nice to get the
* correct behavior simply via automatic promotion (at the cost of some
* memory churn). However, the promoted objects don't behave the same,
* e.g. promoted lightfuncs are extensible.
*/
h = duk_require_hobject_promote_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
#endif
h = duk_require_hobject(ctx, 0);
DUK_ASSERT(h != NULL);
if (is_freeze && DUK_HOBJECT_IS_BUFOBJ(h)) {
/* Buffer objects cannot be frozen because there's no internal
* support for making virtual array indices non-writable.
*/
DUK_DD(DUK_DDPRINT("cannot freeze a buffer object"));
goto fail_cannot_freeze;
}
duk_hobject_object_seal_freeze_helper(thr, h, is_freeze);
/* Sealed and frozen objects cannot gain any more properties,
* so this is a good time to compact them.
*/
duk_hobject_compact_props(thr, h);
return 1;
fail_cannot_freeze:
return DUK_RET_TYPE_ERROR;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_prevent_extensions(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *h;
if (duk_check_type_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER)) {
/* Lightfunc or plain buffer, already non-extensible so always success. */
return 1;
}
h = duk_require_hobject(ctx, 0);
DUK_ASSERT(h != NULL);
DUK_HOBJECT_CLEAR_EXTENSIBLE(h);
/* A non-extensible object cannot gain any more properties,
* so this is a good time to compact.
*/
duk_hobject_compact_props(thr, h);
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_is_sealed_frozen_shared(duk_context *ctx) {
duk_hobject *h;
duk_bool_t is_frozen;
duk_bool_t rc;
duk_uint_t mask;
is_frozen = duk_get_current_magic(ctx);
mask = duk_get_type_mask(ctx, 0);
if (mask & (DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER)) {
DUK_ASSERT(is_frozen == 0 || is_frozen == 1);
duk_push_boolean(ctx, (mask & DUK_TYPE_MASK_LIGHTFUNC) ?
1 : /* lightfunc always frozen and sealed */
(is_frozen ^ 1)); /* buffer sealed but not frozen (index props writable) */
} else {
h = duk_require_hobject(ctx, 0);
rc = duk_hobject_object_is_sealed_frozen_helper((duk_hthread *) ctx, h, is_frozen /*is_frozen*/);
duk_push_boolean(ctx, rc);
}
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_is_extensible(duk_context *ctx) {
duk_hobject *h;
h = duk_require_hobject_accept_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
if (h == NULL) {
duk_push_false(ctx);
} else {
duk_push_boolean(ctx, DUK_HOBJECT_HAS_EXTENSIBLE(h));
}
return 1;
}
/* Shared helper for Object.getOwnPropertyNames() and Object.keys().
* Magic: 0=getOwnPropertyNames, 1=Object.keys.
*/
DUK_INTERNAL duk_ret_t duk_bi_object_constructor_keys_shared(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *obj;
#if defined(DUK_USE_ES6_PROXY)
duk_hobject *h_proxy_target;
duk_hobject *h_proxy_handler;
duk_hobject *h_trap_result;
duk_uarridx_t i, len, idx;
#endif
duk_small_uint_t enum_flags;
DUK_ASSERT_TOP(ctx, 1);
DUK_UNREF(thr);
obj = duk_require_hobject_promote_mask(ctx, 0, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
DUK_ASSERT(obj != NULL);
DUK_UNREF(obj);
#if defined(DUK_USE_ES6_PROXY)
if (DUK_LIKELY(!duk_hobject_proxy_check(thr,
obj,
&h_proxy_target,
&h_proxy_handler))) {
goto skip_proxy;
}
duk_push_hobject(ctx, h_proxy_handler);
if (!duk_get_prop_stridx(ctx, -1, DUK_STRIDX_OWN_KEYS)) {
/* Careful with reachability here: don't pop 'obj' before pushing
* proxy target.
*/
DUK_DDD(DUK_DDDPRINT("no ownKeys trap, get keys of target instead"));
duk_pop_2(ctx);
duk_push_hobject(ctx, h_proxy_target);
duk_replace(ctx, 0);
DUK_ASSERT_TOP(ctx, 1);
goto skip_proxy;
}
/* [ obj handler trap ] */
duk_insert(ctx, -2);
duk_push_hobject(ctx, h_proxy_target); /* -> [ obj trap handler target ] */
duk_call_method(ctx, 1 /*nargs*/); /* -> [ obj trap_result ] */
h_trap_result = duk_require_hobject(ctx, -1);
DUK_UNREF(h_trap_result);
len = (duk_uarridx_t) duk_get_length(ctx, -1);
idx = 0;
duk_push_array(ctx);
for (i = 0; i < len; i++) {
/* [ obj trap_result res_arr ] */
if (duk_get_prop_index(ctx, -2, i) && duk_is_string(ctx, -1)) {
/* XXX: for Object.keys() we should check enumerability of key */
/* [ obj trap_result res_arr propname ] */
duk_put_prop_index(ctx, -2, idx);
idx++;
} else {
duk_pop(ctx);
}
}
/* XXX: missing trap result validation for non-configurable target keys
* (must be present), for non-extensible target all target keys must be
* present and no extra keys can be present.
* http://www.ecma-international.org/ecma-262/6.0/#sec-proxy-object-internal-methods-and-internal-slots-ownpropertykeys
*/
/* XXX: for Object.keys() the [[OwnPropertyKeys]] result (trap result)
* should be filtered so that only enumerable keys remain. Enumerability
* should be checked with [[GetOwnProperty]] on the original object
* (i.e., the proxy in this case). If the proxy has a getOwnPropertyDescriptor
* trap, it should be triggered for every property. If the proxy doesn't have
* the trap, enumerability should be checked against the target object instead.
* We don't do any of this now, so Object.keys() and Object.getOwnPropertyNames()
* return the same result now for proxy traps. We still do clean up the trap
* result, so that Object.keys() and Object.getOwnPropertyNames() will return a
* clean array of strings without gaps.
*/
return 1;
skip_proxy:
#endif /* DUK_USE_ES6_PROXY */
DUK_ASSERT_TOP(ctx, 1);
if (duk_get_current_magic(ctx)) {
/* Object.keys */
enum_flags = DUK_ENUM_OWN_PROPERTIES_ONLY |
DUK_ENUM_NO_PROXY_BEHAVIOR;
} else {
/* Object.getOwnPropertyNames */
enum_flags = DUK_ENUM_INCLUDE_NONENUMERABLE |
DUK_ENUM_OWN_PROPERTIES_ONLY |
DUK_ENUM_NO_PROXY_BEHAVIOR;
}
return duk_hobject_get_enumerated_keys(ctx, enum_flags);
}
DUK_INTERNAL duk_ret_t duk_bi_object_prototype_to_string(duk_context *ctx) {
duk_tval *tv;
tv = DUK_HTHREAD_THIS_PTR((duk_hthread *) ctx);
duk_push_class_string_tval(ctx, tv);
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_prototype_to_locale_string(duk_context *ctx) {
DUK_ASSERT_TOP(ctx, 0);
(void) duk_push_this_coercible_to_object(ctx);
duk_get_prop_stridx(ctx, 0, DUK_STRIDX_TO_STRING);
if (!duk_is_callable(ctx, 1)) {
return DUK_RET_TYPE_ERROR;
}
duk_dup_0(ctx); /* -> [ O toString O ] */
duk_call_method(ctx, 0); /* XXX: call method tail call? */
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_prototype_value_of(duk_context *ctx) {
/* For lightfuncs and plain buffers, returns Object() coerced. */
(void) duk_push_this_coercible_to_object(ctx);
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_prototype_is_prototype_of(duk_context *ctx) {
duk_hthread *thr = (duk_hthread *) ctx;
duk_hobject *h_v;
duk_hobject *h_obj;
DUK_ASSERT_TOP(ctx, 1);
h_v = duk_get_hobject(ctx, 0);
if (!h_v) {
duk_push_false(ctx); /* XXX: tail call: return duk_push_false(ctx) */
return 1;
}
h_obj = duk_push_this_coercible_to_object(ctx);
DUK_ASSERT(h_obj != NULL);
/* E5.1 Section 15.2.4.6, step 3.a, lookup proto once before compare.
* Prototype loops should cause an error to be thrown.
*/
duk_push_boolean(ctx, duk_hobject_prototype_chain_contains(thr, DUK_HOBJECT_GET_PROTOTYPE(thr->heap, h_v), h_obj, 0 /*ignore_loop*/));
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_object_prototype_has_own_property(duk_context *ctx) {
return duk_hobject_object_ownprop_helper(ctx, 0 /*required_desc_flags*/);
}
DUK_INTERNAL duk_ret_t duk_bi_object_prototype_property_is_enumerable(duk_context *ctx) {
return duk_hobject_object_ownprop_helper(ctx, DUK_PROPDESC_FLAG_ENUMERABLE /*required_desc_flags*/);
}