Source code

Revision control

Copy as Markdown

Other Tools

/*
* Any copyright is dedicated to the Public Domain.
*/
var gTestfile = 'proxy-__proto__.js';
var BUGNUMBER = 950407;
var summary = "Behavior of __proto__ on ES6 proxies";
print(BUGNUMBER + ": " + summary);
/**************
* BEGIN TEST *
**************/
var protoDesc = Object.getOwnPropertyDescriptor(Object.prototype, "__proto__");
var protoGetter = protoDesc.get;
var protoSetter = protoDesc.set;
function testProxy(target, initialProto)
{
print("Now testing behavior for new Proxy(" + ("" + target) + ", {})");
var pobj = new Proxy(target, {});
// Check [[Prototype]] before attempted mutation
assertEq(Object.getPrototypeOf(pobj), initialProto);
assertEq(protoGetter.call(pobj), initialProto);
// Attempt [[Prototype]] mutation
protoSetter.call(pobj, null);
// Check [[Prototype]] after attempted mutation
assertEq(Object.getPrototypeOf(pobj), null);
assertEq(protoGetter.call(pobj), null);
assertEq(Object.getPrototypeOf(target), null);
}
// Proxy object with non-null [[Prototype]]
var nonNullProto = { toString: function() { return "non-null prototype"; } };
var target = Object.create(nonNullProto);
testProxy(target, nonNullProto);
// Proxy object with null [[Prototype]]
target = Object.create(null);
target.toString = function() { return "null prototype" };
testProxy(target, null);
// Proxy function with [[Call]]
var callForCallOnly = function () { };
callForCallOnly.toString = function() { return "callable target"; };
testProxy(callForCallOnly, Function.prototype);
/******************************************************************************/
if (typeof reportCompare === "function")
reportCompare(true, true);
print("Tests complete");