// Copyright 2015 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. var target = { target: 1 }; target.__proto__ = {}; var handler = { handler: 1 }; var proxy = new Proxy(target, handler); assertSame(Object.getPrototypeOf(proxy), target.__proto__ ); assertThrows(function() { Object.setPrototypeOf(proxy, undefined) }, TypeError); assertThrows(function() { Object.setPrototypeOf(proxy, 1) }, TypeError); var prototype = [1]; assertSame(proxy, Object.setPrototypeOf(proxy, prototype)); assertSame(prototype, Object.getPrototypeOf(proxy)); assertSame(prototype, Object.getPrototypeOf(target)); var pair = Proxy.revocable(target, handler); assertSame(pair.proxy, Object.setPrototypeOf(pair.proxy, prototype)); assertSame(prototype, Object.getPrototypeOf(pair.proxy)); pair.revoke(); assertThrows('Object.setPrototypeOf(pair.proxy, prototype)', TypeError); handler.setPrototypeOf = function(target, proto) { return false; }; assertThrows(function() { Object.setPrototypeOf(proxy, {a:1}) }, TypeError); handler.setPrototypeOf = function(target, proto) { return undefined; }; assertThrows(function() { Object.setPrototypeOf(proxy, {a:2}) }, TypeError); handler.setPrototypeOf = function(proto) {}; assertThrows(function() { Object.setPrototypeOf(proxy, {a:3}) }, TypeError); handler.setPrototypeOf = function(target, proto) { throw Error(); }; assertThrows(function() { Object.setPrototypeOf(proxy, {a:4}) }, Error); var seen_prototype; var seen_target; handler.setPrototypeOf = function(target, proto) { seen_target = target; seen_prototype = proto; return true; } assertSame(Object.setPrototypeOf(proxy, {a:5}), proxy); assertSame(target, seen_target); assertEquals({a:5}, seen_prototype); (function setPrototypeProxyTarget() { var target = { target: 1 }; target.__proto__ = {}; var handler = {}; var handler2 = {}; var target2 = new Proxy(target, handler2); var proxy2 = new Proxy(target2, handler); assertSame(Object.getPrototypeOf(proxy2), target.__proto__ ); var prototype = [2,3]; assertSame(proxy2, Object.setPrototypeOf(proxy2, prototype)); assertSame(prototype, Object.getPrototypeOf(proxy2)); assertSame(prototype, Object.getPrototypeOf(target)); })(); (function testProxyTrapInconsistent() { var target = { target: 1 }; target.__proto__ = {}; var handler = {}; var handler2 = { }; var target2 = new Proxy(target, handler); var proxy2 = new Proxy(target2, handler2); // If the final target is extensible we can set any prototype. var prototype = [1]; Reflect.setPrototypeOf(proxy2, prototype); assertSame(prototype, Reflect.getPrototypeOf(target)); handler2.setPrototypeOf = function(target, value) { Reflect.setPrototypeOf(target, value); return true; }; prototype = [2]; Reflect.setPrototypeOf(proxy2, prototype); assertSame(prototype, Reflect.getPrototypeOf(target)); // Prevent getting the target's prototype used to check the invariant. var gotPrototype = false; handler.getPrototypeOf = function() { gotPrototype = true; throw TypeError() }; // If the target is extensible we do not check the invariant. prototype = [3]; Reflect.setPrototypeOf(proxy2, prototype); assertFalse(gotPrototype); assertSame(prototype, Reflect.getPrototypeOf(target)); // Changing the prototype of a non-extensible target will trigger the // invariant-check and throw in the above handler. Reflect.preventExtensions(target); assertThrows(() => {Reflect.setPrototypeOf(proxy2, [4])}, TypeError); assertTrue(gotPrototype); assertEquals([3], Reflect.getPrototypeOf(target)); // Setting the prototype of a non-extensible target is fine if the prototype // doesn't change. delete handler.getPrototypeOf; Reflect.setPrototypeOf(proxy2, prototype); // Changing the prototype will throw. prototype = [5]; assertThrows(() => {Reflect.setPrototypeOf(proxy2, prototype)}, TypeError); })(); (function testProxyTrapReturnsFalse() { var handler = {}; handler.setPrototypeOf = () => false; var target = new Proxy({}, {isExtensible: () => assertUnreachable()}); var object = new Proxy(target, handler); assertFalse(Reflect.setPrototypeOf(object, {})); })();