ladybird/Userland/Libraries/LibJS/Runtime/ProxyConstructor.cpp
Linus Groh b99cc7d050 LibJS+LibWeb: Replace GlobalObject with Realm in create() functions
This is a continuation of the previous two commits.

As allocating a JS cell already primarily involves a realm instead of a
global object, and we'll need to pass one to the allocate() function
itself eventually (it's bridged via the global object right now), the
create() functions need to receive a realm as well.
The plan is for this to be the highest-level function that actually
receives a realm and passes it around, AOs on an even higher level will
use the "current realm" concept via VM::current_realm() as that's what
the spec assumes; passing around realms (or global objects, for that
matter) on higher AO levels is pointless and unlike for allocating
individual objects, which may happen outside of regular JS execution, we
don't need control over the specific realm that is being used there.
2022-08-23 13:58:30 +01:00

103 lines
3.9 KiB
C++

/*
* Copyright (c) 2020, Matthew Olsson <mattco@serenityos.org>
* Copyright (c) 2021-2022, 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 {
// 10.5.14 ProxyCreate ( target, handler ), https://tc39.es/ecma262/#sec-proxycreate
static ThrowCompletionOr<ProxyObject*> proxy_create(GlobalObject& global_object, Value target, Value handler)
{
auto& vm = global_object.vm();
auto& realm = *global_object.associated_realm();
if (!target.is_object())
return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyConstructorBadType, "target", target.to_string_without_side_effects());
if (!handler.is_object())
return vm.throw_completion<TypeError>(global_object, ErrorType::ProxyConstructorBadType, "handler", handler.to_string_without_side_effects());
return ProxyObject::create(realm, target.as_object(), handler.as_object());
}
ProxyConstructor::ProxyConstructor(Realm& realm)
: NativeFunction(vm().names.Proxy.as_string(), *realm.global_object().function_prototype())
{
}
void ProxyConstructor::initialize(Realm& realm)
{
auto& vm = this->vm();
NativeFunction::initialize(realm);
u8 attr = Attribute::Writable | Attribute::Configurable;
define_native_function(vm.names.revocable, revocable, 2, attr);
define_direct_property(vm.names.length, Value(2), Attribute::Configurable);
}
// 28.2.1.1 Proxy ( target, handler ), https://tc39.es/ecma262/#sec-proxy-target-handler
ThrowCompletionOr<Value> ProxyConstructor::call()
{
auto& vm = this->vm();
return vm.throw_completion<TypeError>(global_object(), ErrorType::ConstructorWithoutNew, vm.names.Proxy);
}
// 28.2.1.1 Proxy ( target, handler ), https://tc39.es/ecma262/#sec-proxy-target-handler
ThrowCompletionOr<Object*> ProxyConstructor::construct(FunctionObject&)
{
auto& vm = this->vm();
return TRY(proxy_create(global_object(), vm.argument(0), vm.argument(1)));
}
// 28.2.2.1 Proxy.revocable ( target, handler ), https://tc39.es/ecma262/#sec-proxy.revocable
JS_DEFINE_NATIVE_FUNCTION(ProxyConstructor::revocable)
{
auto& realm = *global_object.associated_realm();
// 1. Let p be ? ProxyCreate(target, handler).
auto* proxy = TRY(proxy_create(global_object, vm.argument(0), vm.argument(1)));
// 2. Let revokerClosure be a new Abstract Closure with no parameters that captures nothing and performs the following steps when called:
auto revoker_closure = [proxy_handle = make_handle(proxy)](auto&, auto&) -> ThrowCompletionOr<Value> {
// a. Let F be the active function object.
// b. Let p be F.[[RevocableProxy]].
auto& proxy = const_cast<ProxyObject&>(*proxy_handle.cell());
// c. If p is null, return undefined.
if (proxy.is_revoked())
return js_undefined();
// d. Set F.[[RevocableProxy]] to null.
// e. Assert: p is a Proxy object.
// f. Set p.[[ProxyTarget]] to null.
// g. Set p.[[ProxyHandler]] to null.
proxy.revoke();
// h. Return undefined.
return js_undefined();
};
// 3. Let revoker be CreateBuiltinFunction(revokerClosure, 0, "", « [[RevocableProxy]] »).
// 4. Set revoker.[[RevocableProxy]] to p.
auto* revoker = NativeFunction::create(realm, move(revoker_closure), 0, "");
// 5. Let result be OrdinaryObjectCreate(%Object.prototype%).
auto* result = Object::create(realm, global_object.object_prototype());
// 6. Perform ! CreateDataPropertyOrThrow(result, "proxy", p).
MUST(result->create_data_property_or_throw(vm.names.proxy, proxy));
// 7. Perform ! CreateDataPropertyOrThrow(result, "revoke", revoker).
MUST(result->create_data_property_or_throw(vm.names.revoke, revoker));
// 8. Return result.
return result;
}
}