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			515 lines
		
	
	
	
		
			19 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			515 lines
		
	
	
	
		
			19 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
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|  * Copyright (c) 2020-2021, Linus Groh <linusg@serenityos.org>
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|  *
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|  * SPDX-License-Identifier: BSD-2-Clause
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|  */
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| 
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| #include <AK/Function.h>
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| #include <LibJS/Runtime/AbstractOperations.h>
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| #include <LibJS/Runtime/Array.h>
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| #include <LibJS/Runtime/Error.h>
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| #include <LibJS/Runtime/GlobalObject.h>
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| #include <LibJS/Runtime/IteratorOperations.h>
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| #include <LibJS/Runtime/ObjectConstructor.h>
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| #include <LibJS/Runtime/ProxyObject.h>
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| #include <LibJS/Runtime/Shape.h>
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| 
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| namespace JS {
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| 
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| ObjectConstructor::ObjectConstructor(GlobalObject& global_object)
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|     : NativeFunction(vm().names.Object.as_string(), *global_object.function_prototype())
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| {
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| }
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| 
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| void ObjectConstructor::initialize(GlobalObject& global_object)
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| {
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|     auto& vm = this->vm();
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|     NativeFunction::initialize(global_object);
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| 
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|     // 20.1.2.19 Object.prototype, https://tc39.es/ecma262/#sec-object.prototype
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|     define_direct_property(vm.names.prototype, global_object.object_prototype(), 0);
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| 
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|     u8 attr = Attribute::Writable | Attribute::Configurable;
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|     define_native_function(vm.names.defineProperty, define_property, 3, attr);
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|     define_native_function(vm.names.defineProperties, define_properties, 2, attr);
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|     define_native_function(vm.names.is, is, 2, attr);
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|     define_native_function(vm.names.getOwnPropertyDescriptor, get_own_property_descriptor, 2, attr);
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|     define_native_function(vm.names.getOwnPropertyDescriptors, get_own_property_descriptors, 1, attr);
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|     define_native_function(vm.names.getOwnPropertyNames, get_own_property_names, 1, attr);
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|     define_native_function(vm.names.getOwnPropertySymbols, get_own_property_symbols, 1, attr);
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|     define_native_function(vm.names.getPrototypeOf, get_prototype_of, 1, attr);
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|     define_native_function(vm.names.setPrototypeOf, set_prototype_of, 2, attr);
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|     define_native_function(vm.names.isExtensible, is_extensible, 1, attr);
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|     define_native_function(vm.names.isFrozen, is_frozen, 1, attr);
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|     define_native_function(vm.names.isSealed, is_sealed, 1, attr);
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|     define_native_function(vm.names.preventExtensions, prevent_extensions, 1, attr);
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|     define_native_function(vm.names.freeze, freeze, 1, attr);
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|     define_native_function(vm.names.fromEntries, from_entries, 1, attr);
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|     define_native_function(vm.names.seal, seal, 1, attr);
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|     define_native_function(vm.names.keys, keys, 1, attr);
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|     define_native_function(vm.names.values, values, 1, attr);
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|     define_native_function(vm.names.entries, entries, 1, attr);
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|     define_native_function(vm.names.create, create, 2, attr);
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|     define_native_function(vm.names.hasOwn, has_own, 2, attr);
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|     define_native_function(vm.names.assign, assign, 2, attr);
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| 
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|     define_direct_property(vm.names.length, Value(1), Attribute::Configurable);
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| }
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| 
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| ObjectConstructor::~ObjectConstructor()
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| {
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| }
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| 
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| // 20.1.1.1 Object ( [ value ] ), https://tc39.es/ecma262/#sec-object-value
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| Value ObjectConstructor::call()
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| {
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|     return construct(*this);
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| }
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| 
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| // 20.1.1.1 Object ( [ value ] ), https://tc39.es/ecma262/#sec-object-value
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| Value ObjectConstructor::construct(FunctionObject& new_target)
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| {
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|     auto& vm = this->vm();
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|     auto& global_object = this->global_object();
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| 
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|     if (&new_target != this)
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|         return ordinary_create_from_constructor<Object>(global_object, new_target, &GlobalObject::object_prototype);
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|     auto value = vm.argument(0);
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|     if (value.is_nullish())
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|         return Object::create(global_object, global_object.object_prototype());
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|     return value.to_object(global_object);
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| }
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| 
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| enum class GetOwnPropertyKeysType {
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|     String,
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|     Symbol,
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| };
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| 
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| // 20.1.2.11.1 GetOwnPropertyKeys ( O, type ), https://tc39.es/ecma262/#sec-getownpropertykeys
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| static Array* get_own_property_keys(GlobalObject& global_object, Value value, GetOwnPropertyKeysType type)
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| {
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|     auto& vm = global_object.vm();
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| 
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|     // 1. Let obj be ? ToObject(O).
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|     auto* object = value.to_object(global_object);
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|     if (vm.exception())
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|         return {};
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| 
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|     // 2. Let keys be ? obj.[[OwnPropertyKeys]]().
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|     auto keys = object->internal_own_property_keys();
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|     if (vm.exception())
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|         return {};
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| 
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|     // 3. Let nameList be a new empty List.
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|     auto name_list = MarkedValueList { vm.heap() };
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| 
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|     // 4. For each element nextKey of keys, do
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|     for (auto& next_key : keys) {
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|         // a. If Type(nextKey) is Symbol and type is symbol or Type(nextKey) is String and type is string, then
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|         if ((next_key.is_symbol() && type == GetOwnPropertyKeysType::Symbol) || (next_key.is_string() && type == GetOwnPropertyKeysType::String)) {
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|             // i. Append nextKey as the last element of nameList.
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|             name_list.append(next_key);
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|         }
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|     }
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| 
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|     // 5. Return CreateArrayFromList(nameList).
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|     return Array::create_from(global_object, name_list);
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| }
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| 
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| // 20.1.2.10 Object.getOwnPropertyNames ( O ), https://tc39.es/ecma262/#sec-object.getownpropertynames
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::get_own_property_names)
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| {
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|     // 1. Return ? GetOwnPropertyKeys(O, string).
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|     return get_own_property_keys(global_object, vm.argument(0), GetOwnPropertyKeysType::String);
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| }
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| 
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| // 20.1.2.11 Object.getOwnPropertySymbols ( O ), https://tc39.es/ecma262/#sec-object.getownpropertysymbols
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::get_own_property_symbols)
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| {
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|     // 1. Return ? GetOwnPropertyKeys(O, symbol).
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|     return get_own_property_keys(global_object, vm.argument(0), GetOwnPropertyKeysType::Symbol);
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| }
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| 
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| // 20.1.2.12 Object.getPrototypeOf ( O ), https://tc39.es/ecma262/#sec-object.getprototypeof
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::get_prototype_of)
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| {
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|     // 1. Let obj be ? ToObject(O).
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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| 
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|     // 2. Return ? obj.[[GetPrototypeOf]]().
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|     return object->internal_get_prototype_of();
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| }
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| 
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| // 20.1.2.21 Object.setPrototypeOf ( O, proto ), https://tc39.es/ecma262/#sec-object.setprototypeof
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::set_prototype_of)
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| {
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|     auto proto = vm.argument(1);
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| 
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|     // 1. Set O to ? RequireObjectCoercible(O).
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|     auto object = TRY_OR_DISCARD(require_object_coercible(global_object, vm.argument(0)));
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| 
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|     // 2. If Type(proto) is neither Object nor Null, throw a TypeError exception.
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|     if (!proto.is_object() && !proto.is_null()) {
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|         vm.throw_exception<TypeError>(global_object, ErrorType::ObjectPrototypeWrongType);
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|         return {};
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|     }
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| 
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|     // 3. If Type(O) is not Object, return O.
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|     if (!object.is_object())
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|         return object;
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| 
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|     // 4. Let status be ? O.[[SetPrototypeOf]](proto).
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|     auto status = object.as_object().internal_set_prototype_of(proto.is_null() ? nullptr : &proto.as_object());
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|     if (vm.exception())
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|         return {};
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| 
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|     // 5. If status is false, throw a TypeError exception.
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|     if (!status) {
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|         // FIXME: Improve/contextualize error message
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|         vm.throw_exception<TypeError>(global_object, ErrorType::ObjectSetPrototypeOfReturnedFalse);
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|         return {};
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|     }
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| 
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|     // 6. Return O.
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|     return object;
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| }
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| 
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| // 20.1.2.14 Object.isExtensible ( O ), https://tc39.es/ecma262/#sec-object.isextensible
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::is_extensible)
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| {
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|     auto argument = vm.argument(0);
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|     if (!argument.is_object())
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|         return Value(false);
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|     return Value(argument.as_object().is_extensible());
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| }
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| 
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| // 20.1.2.15 Object.isFrozen ( O ), https://tc39.es/ecma262/#sec-object.isfrozen
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::is_frozen)
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| {
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|     auto argument = vm.argument(0);
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|     if (!argument.is_object())
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|         return Value(true);
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|     return Value(argument.as_object().test_integrity_level(Object::IntegrityLevel::Frozen));
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| }
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| 
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| // 20.1.2.16 Object.isSealed ( O ), https://tc39.es/ecma262/#sec-object.issealed
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::is_sealed)
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| {
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|     auto argument = vm.argument(0);
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|     if (!argument.is_object())
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|         return Value(true);
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|     return Value(argument.as_object().test_integrity_level(Object::IntegrityLevel::Sealed));
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| }
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| 
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| // 20.1.2.18 Object.preventExtensions ( O ), https://tc39.es/ecma262/#sec-object.preventextensions
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::prevent_extensions)
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| {
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|     auto argument = vm.argument(0);
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|     if (!argument.is_object())
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|         return argument;
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|     auto status = argument.as_object().internal_prevent_extensions();
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|     if (vm.exception())
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|         return {};
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|     if (!status) {
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|         // FIXME: Improve/contextualize error message
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|         vm.throw_exception<TypeError>(global_object, ErrorType::ObjectPreventExtensionsReturnedFalse);
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|         return {};
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|     }
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|     return argument;
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| }
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| 
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| // 20.1.2.6 Object.freeze ( O ), https://tc39.es/ecma262/#sec-object.freeze
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::freeze)
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| {
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|     auto argument = vm.argument(0);
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|     if (!argument.is_object())
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|         return argument;
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|     auto status = argument.as_object().set_integrity_level(Object::IntegrityLevel::Frozen);
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|     if (vm.exception())
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|         return {};
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|     if (!status) {
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|         vm.throw_exception<TypeError>(global_object, ErrorType::ObjectFreezeFailed);
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|         return {};
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|     }
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|     return argument;
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| }
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| 
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| // 20.1.2.7 Object.fromEntries ( iterable ), https://tc39.es/ecma262/#sec-object.fromentries
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::from_entries)
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| {
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|     auto iterable = TRY_OR_DISCARD(require_object_coercible(global_object, vm.argument(0)));
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| 
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|     auto* object = Object::create(global_object, global_object.object_prototype());
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| 
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|     get_iterator_values(global_object, iterable, [&](Value iterator_value) {
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|         if (vm.exception())
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|             return IterationDecision::Break;
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|         if (!iterator_value.is_object()) {
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|             vm.throw_exception<TypeError>(global_object, ErrorType::NotAnObject, String::formatted("Iterator value {}", iterator_value.to_string_without_side_effects()));
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|             return IterationDecision::Break;
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|         }
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|         auto key = iterator_value.as_object().get(0);
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|         if (vm.exception())
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|             return IterationDecision::Break;
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|         auto value = iterator_value.as_object().get(1);
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|         if (vm.exception())
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|             return IterationDecision::Break;
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|         auto property_key = key.to_property_key(global_object);
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|         if (vm.exception())
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|             return IterationDecision::Break;
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|         object->create_data_property_or_throw(property_key, value);
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|         if (vm.exception())
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|             return IterationDecision::Break;
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|         return IterationDecision::Continue;
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|     });
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|     if (vm.exception())
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|         return {};
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|     return object;
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| }
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| 
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| // 20.1.2.20 Object.seal ( O ), https://tc39.es/ecma262/#sec-object.seal
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::seal)
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| {
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|     auto argument = vm.argument(0);
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|     if (!argument.is_object())
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|         return argument;
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|     auto status = argument.as_object().set_integrity_level(Object::IntegrityLevel::Sealed);
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|     if (vm.exception())
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|         return {};
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|     if (!status) {
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|         vm.throw_exception<TypeError>(global_object, ErrorType::ObjectSealFailed);
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|         return {};
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|     }
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|     return argument;
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| }
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| 
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| // 20.1.2.8 Object.getOwnPropertyDescriptor ( O, P ), https://tc39.es/ecma262/#sec-object.getownpropertydescriptor
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::get_own_property_descriptor)
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| {
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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|     auto key = vm.argument(1).to_property_key(global_object);
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|     if (vm.exception())
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|         return {};
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|     auto descriptor = object->internal_get_own_property(key);
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|     if (vm.exception())
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|         return {};
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|     return from_property_descriptor(global_object, descriptor);
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| }
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| 
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| // 20.1.2.9 Object.getOwnPropertyDescriptors ( O ), https://tc39.es/ecma262/#sec-object.getownpropertydescriptors
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::get_own_property_descriptors)
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| {
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|     // 1. Let obj be ? ToObject(O).
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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|     // 2. Let ownKeys be ? obj.[[OwnPropertyKeys]]().
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|     auto own_keys = object->internal_own_property_keys();
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|     if (vm.exception())
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|         return {};
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|     // 3. Let descriptors be ! OrdinaryObjectCreate(%Object.prototype%).
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|     auto* descriptors = Object::create(global_object, global_object.object_prototype());
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|     // 4. For each element key of ownKeys, do
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|     for (auto& key : own_keys) {
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|         auto property_name = PropertyName::from_value(global_object, key);
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| 
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|         // a. Let desc be ? obj.[[GetOwnProperty]](key).
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|         auto desc = object->internal_get_own_property(property_name);
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|         if (vm.exception())
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|             return {};
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| 
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|         // b. Let descriptor be ! FromPropertyDescriptor(desc).
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|         auto descriptor = from_property_descriptor(global_object, desc);
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| 
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|         // c. If descriptor is not undefined, perform ! CreateDataPropertyOrThrow(descriptors, key, descriptor).
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|         if (!descriptor.is_undefined())
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|             descriptors->create_data_property_or_throw(property_name, descriptor);
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|     }
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| 
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|     // 5. Return descriptors.
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|     return descriptors;
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| }
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| 
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| // 20.1.2.4 Object.defineProperty ( O, P, Attributes ), https://tc39.es/ecma262/#sec-object.defineproperty
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::define_property)
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| {
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|     if (!vm.argument(0).is_object()) {
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|         vm.throw_exception<TypeError>(global_object, ErrorType::NotAnObject, vm.argument(0).to_string_without_side_effects());
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|         return {};
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|     }
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|     auto key = vm.argument(1).to_property_key(global_object);
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|     if (vm.exception())
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|         return {};
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|     auto descriptor = to_property_descriptor(global_object, vm.argument(2));
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|     if (vm.exception())
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|         return {};
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|     vm.argument(0).as_object().define_property_or_throw(key, descriptor);
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|     if (vm.exception())
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|         return {};
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|     return vm.argument(0);
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| }
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| 
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| // 20.1.2.3 Object.defineProperties ( O, Properties ), https://tc39.es/ecma262/#sec-object.defineproperties
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::define_properties)
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| {
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|     auto object = vm.argument(0);
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|     auto properties = vm.argument(1);
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| 
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|     // 1. If Type(O) is not Object, throw a TypeError exception.
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|     if (!object.is_object()) {
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|         vm.throw_exception<TypeError>(global_object, ErrorType::NotAnObject, "Object argument");
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|         return {};
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|     }
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| 
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|     // 2. Return ? ObjectDefineProperties(O, Properties).
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|     return object.as_object().define_properties(properties);
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| }
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| 
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| // 20.1.2.13 Object.is ( value1, value2 ), https://tc39.es/ecma262/#sec-object.is
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::is)
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| {
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|     return Value(same_value(vm.argument(0), vm.argument(1)));
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| }
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| 
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| // 20.1.2.17 Object.keys ( O ), https://tc39.es/ecma262/#sec-object.keys
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::keys)
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| {
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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|     auto name_list = object->enumerable_own_property_names(PropertyKind::Key);
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|     if (vm.exception())
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|         return {};
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|     return Array::create_from(global_object, name_list);
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| }
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| 
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| // 20.1.2.22 Object.values ( O ), https://tc39.es/ecma262/#sec-object.values
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::values)
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| {
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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|     auto name_list = object->enumerable_own_property_names(PropertyKind::Value);
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|     if (vm.exception())
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|         return {};
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|     return Array::create_from(global_object, name_list);
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| }
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| 
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| // 20.1.2.5 Object.entries ( O ), https://tc39.es/ecma262/#sec-object.entries
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::entries)
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| {
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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|     auto name_list = object->enumerable_own_property_names(PropertyKind::KeyAndValue);
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|     if (vm.exception())
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|         return {};
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|     return Array::create_from(global_object, name_list);
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| }
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| 
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| // 20.1.2.2 Object.create ( O, Properties ), https://tc39.es/ecma262/#sec-object.create
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::create)
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| {
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|     auto proto = vm.argument(0);
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|     auto properties = vm.argument(1);
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| 
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|     // 1. If Type(O) is neither Object nor Null, throw a TypeError exception.
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|     if (!proto.is_object() && !proto.is_null()) {
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|         vm.throw_exception<TypeError>(global_object, ErrorType::ObjectPrototypeWrongType);
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|         return {};
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|     }
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| 
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|     // 2. Let obj be ! OrdinaryObjectCreate(O).
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|     auto* object = Object::create(global_object, proto.is_null() ? nullptr : &proto.as_object());
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| 
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|     // 3. If Properties is not undefined, then
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|     if (!properties.is_undefined()) {
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|         // a. Return ? ObjectDefineProperties(obj, Properties).
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|         return object->define_properties(properties);
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|     }
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| 
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|     // 4. Return obj.
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|     return object;
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| }
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| 
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| // 1 Object.hasOwn ( O, P ), https://tc39.es/proposal-accessible-object-hasownproperty/#sec-object.hasown
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| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::has_own)
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| {
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|     // 1. Let obj be ? ToObject(O).
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|     auto* object = vm.argument(0).to_object(global_object);
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|     if (vm.exception())
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|         return {};
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| 
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|     // 2. Let key be ? ToPropertyKey(P).
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|     auto key = vm.argument(1).to_property_key(global_object);
 | |
|     if (vm.exception())
 | |
|         return {};
 | |
| 
 | |
|     // 3. Return ? HasOwnProperty(obj, key).
 | |
|     return Value(object->has_own_property(key));
 | |
| }
 | |
| 
 | |
| // 20.1.2.1 Object.assign ( target, ...sources ), https://tc39.es/ecma262/#sec-object.assign
 | |
| JS_DEFINE_NATIVE_FUNCTION(ObjectConstructor::assign)
 | |
| {
 | |
|     // 1. Let to be ? ToObject(target).
 | |
|     auto* to = vm.argument(0).to_object(global_object);
 | |
|     if (vm.exception())
 | |
|         return {};
 | |
| 
 | |
|     // 2. If only one argument was passed, return to.
 | |
|     if (vm.argument_count() == 1)
 | |
|         return to;
 | |
| 
 | |
|     // 3. For each element nextSource of sources, do
 | |
|     for (size_t i = 1; i < vm.argument_count(); ++i) {
 | |
|         auto next_source = vm.argument(i);
 | |
| 
 | |
|         // a. If nextSource is neither undefined nor null, then
 | |
|         if (next_source.is_nullish())
 | |
|             continue;
 | |
| 
 | |
|         // i. Let from be ! ToObject(nextSource).
 | |
|         auto from = next_source.to_object(global_object);
 | |
|         VERIFY(!vm.exception());
 | |
| 
 | |
|         // ii. Let keys be ? from.[[OwnPropertyKeys]]().
 | |
|         auto keys = from->internal_own_property_keys();
 | |
|         if (vm.exception())
 | |
|             return {};
 | |
| 
 | |
|         // iii. For each element nextKey of keys, do
 | |
|         for (auto& next_key : keys) {
 | |
|             auto property_name = PropertyName::from_value(global_object, next_key);
 | |
| 
 | |
|             // 1. Let desc be ? from.[[GetOwnProperty]](nextKey).
 | |
|             auto desc = from->internal_get_own_property(property_name);
 | |
|             if (vm.exception())
 | |
|                 return {};
 | |
| 
 | |
|             // 2. If desc is not undefined and desc.[[Enumerable]] is true, then
 | |
|             if (!desc.has_value() || !*desc->enumerable)
 | |
|                 continue;
 | |
| 
 | |
|             // a. Let propValue be ? Get(from, nextKey).
 | |
|             auto prop_value = from->get(property_name);
 | |
|             if (vm.exception())
 | |
|                 return {};
 | |
| 
 | |
|             // b. Perform ? Set(to, nextKey, propValue, true).
 | |
|             to->set(property_name, prop_value, Object::ShouldThrowExceptions::Yes);
 | |
|             if (vm.exception())
 | |
|                 return {};
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     // 4. Return to.
 | |
|     return to;
 | |
| }
 | |
| 
 | |
| }
 | 
