v8/test/mjsunit/es6/proxies-keys.js
2016-07-11 10:39:35 +00:00

79 lines
2.2 KiB
JavaScript

// 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__ = {
target_proto: 2
};
var handler = {
ownKeys: function(target) {
return ["foo", "bar", Symbol("baz"), "non-enum", "not-found"];
},
getOwnPropertyDescriptor: function(target, name) {
if (name == "non-enum") return {configurable: true};
if (name == "not-found") return undefined;
return {enumerable: true, configurable: true};
}
}
var proxy = new Proxy(target, handler);
// Object.keys() ignores symbols and non-enumerable keys.
assertEquals(["foo", "bar"], Object.keys(proxy));
// Edge case: no properties left after filtering.
handler.getOwnPropertyDescriptor = undefined;
assertEquals([], Object.keys(proxy));
// Throwing shouldn't crash.
handler.getOwnPropertyDescriptor = function() { throw new Number(1); };
assertThrows("Object.keys(proxy)", Number);
// Fall through to target if there is no trap.
handler.ownKeys = undefined;
assertEquals(["target"], Object.keys(proxy));
assertEquals(["target"], Object.keys(target));
var proxy2 = new Proxy(proxy, {});
assertEquals(["target"], Object.keys(proxy2));
(function testForSymbols() {
var symbol = Symbol();
var p = new Proxy({}, {ownKeys() { return ["1", symbol, "2"] }});
assertEquals(["1","2"], Object.getOwnPropertyNames(p));
assertEquals([symbol], Object.getOwnPropertySymbols(p));
})();
(function testNoProxyTraps() {
var test_sym = Symbol("sym1");
var test_sym2 = Symbol("sym2");
var target = {
one: 1,
two: 2,
[test_sym]: 4,
0: 0,
};
Object.defineProperty(
target, "non-enum",
{ enumerable: false, value: "nope", configurable: true, writable: true });
target.__proto__ = {
target_proto: 3,
1: 1,
[test_sym2]: 5
};
Object.defineProperty(
target.__proto__, "non-enum2",
{ enumerable: false, value: "nope", configurable: true, writable: true });
var proxy = new Proxy(target, {});
assertEquals(["0", "one", "two"], Object.keys(proxy));
assertEquals(["0", "one", "two", "non-enum"],
Object.getOwnPropertyNames(proxy));
assertEquals([test_sym], Object.getOwnPropertySymbols(proxy));
})();