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// Copyright 2019 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include 'src/builtins/builtins-proxy-gen.h'
namespace proxy {
// ES #sec-proxy-object-internal-methods-and-internal-slots-setprototypeof-v
// https://tc39.es/ecma262/#sec-proxy-object-internal-methods-and-internal-slots-setprototypeof-v
transitioning builtin
ProxySetPrototypeOf(implicit context: Context)(
proxy: JSProxy, proto: Object, doThrow: Boolean): Object {
PerformStackCheck();
const kTrapName: constexpr string = 'setPrototypeOf';
try {
// 1. Assert: Either Type(V) is Object or Type(V) is Null.
assert(proto == Null || Is<JSReceiver>(proto));
// 2. Let handler be O.[[ProxyHandler]].
// 3. If handler is null, throw a TypeError exception.
// 4. Assert: Type(handler) is Object.
assert(proxy.handler == Null || Is<JSReceiver>(proxy.handler));
const handler =
Cast<JSReceiver>(proxy.handler) otherwise ThrowProxyHandlerRevoked;
// 5. Let target be O.[[ProxyTarget]].
const target = proxy.target;
// 6. Let trap be ? GetMethod(handler, "setPrototypeOf").
// 7. If trap is undefined, then (see 7.a below).
const trap: Callable = GetMethod(handler, kTrapName)
otherwise goto TrapUndefined(target, proto);
// 8. Let booleanTrapResult be ToBoolean(? Call(trap, handler, « target, V
// »)).
const trapResult = Call(context, trap, handler, target, proto);
// 9. If booleanTrapResult is false, return false.
if (BranchIfToBooleanIsFalse(trapResult)) {
if (doThrow == True) {
ThrowTypeError(kProxyTrapReturnedFalsishFor, kTrapName);
}
return False;
}
// 10. Let extensibleTarget be ? IsExtensible(target).
// 11. If extensibleTarget is true, return true.
const extensibleTarget: Object = object::ObjectIsExtensible(target);
assert(extensibleTarget == True || extensibleTarget == False);
if (extensibleTarget == True) {
return True;
}
// 12. Let targetProto be ? target.[[GetPrototypeOf]]().
const targetProto = object::ObjectGetPrototypeOf(target);
// 13. If SameValue(V, targetProto) is false, throw a TypeError
// exception.
// 14. Return true.
if (BranchIfSameValue(proto, targetProto)) {
return True;
}
ThrowTypeError(kProxySetPrototypeOfNonExtensible);
}
label TrapUndefined(target: Object, proto: Object) {
// 7.a. Return ? target.[[SetPrototypeOf]]().
if (doThrow == True) {
return object::ObjectSetPrototypeOfThrow(target, proto);
}
return object::ObjectSetPrototypeOfDontThrow(target, proto);
}
label ThrowProxyHandlerRevoked deferred {
ThrowTypeError(kProxyRevoked, kTrapName);
}
}
}
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