ladybird/Userland/Libraries/LibJS/Runtime/ProxyConstructor.cpp
2021-06-08 23:53:13 +02:00

87 lines
3 KiB
C++

/*
* Copyright (c) 2020, Matthew Olsson <mattco@serenityos.org>
* Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/Runtime/Array.h>
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/GlobalObject.h>
#include <LibJS/Runtime/ProxyConstructor.h>
#include <LibJS/Runtime/ProxyObject.h>
namespace JS {
static ProxyObject* proxy_create(GlobalObject& global_object, Value target, Value handler)
{
auto& vm = global_object.vm();
if (!target.is_object()) {
vm.throw_exception<TypeError>(global_object, ErrorType::ProxyConstructorBadType, "target", target.to_string_without_side_effects());
return {};
}
if (!handler.is_object()) {
vm.throw_exception<TypeError>(global_object, ErrorType::ProxyConstructorBadType, "handler", handler.to_string_without_side_effects());
return {};
}
return ProxyObject::create(global_object, target.as_object(), handler.as_object());
}
ProxyConstructor::ProxyConstructor(GlobalObject& global_object)
: NativeFunction(vm().names.Proxy, *global_object.function_prototype())
{
}
void ProxyConstructor::initialize(GlobalObject& global_object)
{
auto& vm = this->vm();
NativeFunction::initialize(global_object);
define_property(vm.names.length, Value(2), Attribute::Configurable);
u8 attr = Attribute::Writable | Attribute::Configurable;
define_native_function(vm.names.revocable, revocable, 2, attr);
}
ProxyConstructor::~ProxyConstructor()
{
}
Value ProxyConstructor::call()
{
auto& vm = this->vm();
vm.throw_exception<TypeError>(global_object(), ErrorType::ConstructorWithoutNew, vm.names.Proxy);
return {};
}
Value ProxyConstructor::construct(Function&)
{
auto& vm = this->vm();
return proxy_create(global_object(), vm.argument(0), vm.argument(1));
}
// 28.2.2.1 Proxy.revocable, https://tc39.es/ecma262/multipage/reflection.html#sec-proxy.revocable
JS_DEFINE_NATIVE_FUNCTION(ProxyConstructor::revocable)
{
auto* proxy = proxy_create(global_object, vm.argument(0), vm.argument(1));
if (vm.exception())
return {};
// 28.2.2.1.1 Proxy Revocation Functions, https://tc39.es/ecma262/multipage/reflection.html#sec-proxy-revocation-functions
auto* revoker = NativeFunction::create(global_object, "", [proxy_handle = make_handle(proxy)](auto&, auto&) -> Value {
auto& proxy = const_cast<ProxyObject&>(*proxy_handle.cell());
if (proxy.is_revoked())
return js_undefined();
// NOTE: The spec wants us to unset [[ProxyTarget]] and [[ProxyHandler]],
// which is their way of revoking the Proxy - this might affect GC-ability,
// but AFAICT not doing that should be ok compatibility-wise.
proxy.revoke();
return js_undefined();
});
revoker->define_property(vm.names.length, Value(0));
auto* result = Object::create_empty(global_object);
result->define_property(vm.names.proxy, proxy);
result->define_property(vm.names.revoke, revoker);
return result;
}
}