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/*
* Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/FunctionObject.h>
#include <LibJS/Runtime/GlobalObject.h>
#include <LibJS/Runtime/Object.h>
#include <LibJS/Runtime/PropertyDescriptor.h>
#include <LibJS/Runtime/Value.h>
namespace JS {
// 6.2.5.1 IsAccessorDescriptor ( Desc ), https://tc39.es/ecma262/#sec-isaccessordescriptor
bool PropertyDescriptor::is_accessor_descriptor() const
{
// 1. If Desc is undefined, return false.
// 2. If both Desc.[[Get]] and Desc.[[Set]] are absent, return false.
if (!get.has_value() && !set.has_value())
return false;
// 3. Return true.
return true;
}
// 6.2.5.2 IsDataDescriptor ( Desc ), https://tc39.es/ecma262/#sec-isdatadescriptor
bool PropertyDescriptor::is_data_descriptor() const
{
// 1. If Desc is undefined, return false.
// 2. If both Desc.[[Value]] and Desc.[[Writable]] are absent, return false.
if (!value.has_value() && !writable.has_value())
return false;
// 3. Return true.
return true;
}
// 6.2.5.3 IsGenericDescriptor ( Desc ), https://tc39.es/ecma262/#sec-isgenericdescriptor
bool PropertyDescriptor::is_generic_descriptor() const
{
// 1. If Desc is undefined, return false.
// 2. If IsAccessorDescriptor(Desc) and IsDataDescriptor(Desc) are both false, return true.
if (!is_accessor_descriptor() && !is_data_descriptor())
return true;
// 3. Return false.
return false;
}
// 6.2.5.4 FromPropertyDescriptor ( Desc ), https://tc39.es/ecma262/#sec-frompropertydescriptor
Value from_property_descriptor(GlobalObject& global_object, Optional<PropertyDescriptor> const& property_descriptor)
{
if (!property_descriptor.has_value())
return js_undefined();
auto& vm = global_object.vm();
auto* object = Object::create(global_object, global_object.object_prototype());
if (property_descriptor->value.has_value())
object->create_data_property_or_throw(vm.names.value, *property_descriptor->value);
if (property_descriptor->writable.has_value())
object->create_data_property_or_throw(vm.names.writable, Value(*property_descriptor->writable));
if (property_descriptor->get.has_value())
object->create_data_property_or_throw(vm.names.get, *property_descriptor->get ? Value(*property_descriptor->get) : js_undefined());
if (property_descriptor->set.has_value())
object->create_data_property_or_throw(vm.names.set, *property_descriptor->set ? Value(*property_descriptor->set) : js_undefined());
if (property_descriptor->enumerable.has_value())
object->create_data_property_or_throw(vm.names.enumerable, Value(*property_descriptor->enumerable));
if (property_descriptor->configurable.has_value())
object->create_data_property_or_throw(vm.names.configurable, Value(*property_descriptor->configurable));
return object;
}
// 6.2.5.5 ToPropertyDescriptor ( Obj ), https://tc39.es/ecma262/#sec-topropertydescriptor
PropertyDescriptor to_property_descriptor(GlobalObject& global_object, Value argument)
{
auto& vm = global_object.vm();
if (!argument.is_object()) {
vm.throw_exception<TypeError>(global_object, ErrorType::NotAnObject, argument.to_string_without_side_effects());
return {};
}
auto& object = argument.as_object();
PropertyDescriptor descriptor;
auto has_enumerable = object.has_property(vm.names.enumerable);
if (vm.exception())
return {};
if (has_enumerable) {
auto enumerable = object.get(vm.names.enumerable);
if (vm.exception())
return {};
descriptor.enumerable = enumerable.to_boolean();
}
auto has_configurable = object.has_property(vm.names.configurable);
if (vm.exception())
return {};
if (has_configurable) {
auto configurable = object.get(vm.names.configurable);
if (vm.exception())
return {};
descriptor.configurable = configurable.to_boolean();
}
auto has_value = object.has_property(vm.names.value);
if (vm.exception())
return {};
if (has_value) {
auto value = object.get(vm.names.value);
if (vm.exception())
return {};
descriptor.value = value;
}
auto has_writable = object.has_property(vm.names.writable);
if (vm.exception())
return {};
if (has_writable) {
auto writable = object.get(vm.names.writable);
if (vm.exception())
return {};
descriptor.writable = writable.to_boolean();
}
auto has_get = object.has_property(vm.names.get);
if (vm.exception())
return {};
if (has_get) {
auto getter = object.get(vm.names.get);
if (vm.exception())
return {};
if (!getter.is_function() && !getter.is_undefined()) {
vm.throw_exception<TypeError>(global_object, ErrorType::AccessorBadField, "get");
return {};
}
descriptor.get = getter.is_function() ? &getter.as_function() : nullptr;
}
auto has_set = object.has_property(vm.names.set);
if (vm.exception())
return {};
if (has_set) {
auto setter = object.get(vm.names.set);
if (vm.exception())
return {};
if (!setter.is_function() && !setter.is_undefined()) {
vm.throw_exception<TypeError>(global_object, ErrorType::AccessorBadField, "set");
return {};
}
descriptor.set = setter.is_function() ? &setter.as_function() : nullptr;
}
if (descriptor.get.has_value() || descriptor.set.has_value()) {
if (descriptor.value.has_value() || descriptor.writable.has_value()) {
vm.throw_exception<TypeError>(global_object, ErrorType::AccessorValueOrWritable);
return {};
}
}
return descriptor;
}
// 6.2.5.6 CompletePropertyDescriptor ( Desc ), https://tc39.es/ecma262/#sec-completepropertydescriptor
void PropertyDescriptor::complete()
{
if (is_generic_descriptor() || is_data_descriptor()) {
if (!value.has_value())
value = Value {};
if (!writable.has_value())
writable = false;
} else {
if (!get.has_value())
get = nullptr;
if (!set.has_value())
set = nullptr;
}
if (!enumerable.has_value())
enumerable = false;
if (!configurable.has_value())
configurable = false;
}
// Non-standard, just a convenient way to get from three Optional<bool> to PropertyAttributes.
PropertyAttributes PropertyDescriptor::attributes() const
{
u8 attributes = 0;
if (writable.value_or(false))
attributes |= Attribute::Writable;
if (enumerable.value_or(false))
attributes |= Attribute::Enumerable;
if (configurable.value_or(false))
attributes |= Attribute::Configurable;
return { attributes };
}
}
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