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// 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.
// Flags: --harmony-proxies
var target = {
"target_one": 1
};
target.__proto__ = {
"target_two": 2
};
var handler = {
enumerate: function(target) {
function* keys() {
yield "foo";
yield "bar";
}
return keys();
},
// For-in calls "has" on every iteration, so for TestForIn() below to
// detect all results of the "enumerate" trap, "has" must return true.
has: function(target, name) {
return true;
}
}
var proxy = new Proxy(target, handler);
function TestForIn(receiver, expected) {
var result = [];
for (var k in receiver) {
result.push(k);
}
assertEquals(expected, result);
}
TestForIn(proxy, ["foo", "bar"]);
// Test revoked proxy.
var pair = Proxy.revocable(target, handler);
TestForIn(pair.proxy, ["foo", "bar"]);
pair.revoke();
assertThrows(()=>{ TestForIn(pair.proxy, ["foo", "bar"]) }, TypeError);
// Properly call traps on proxies on the prototype chain.
var receiver = {
"receiver_one": 1
};
receiver.__proto__ = proxy;
TestForIn(receiver, ["receiver_one", "foo", "bar"]);
// Fall through to default behavior when trap is undefined.
handler.enumerate = undefined;
TestForIn(proxy, ["target_one", "target_two"]);
delete handler.enumerate;
TestForIn(proxy, ["target_one", "target_two"]);
// Non-string keys must be filtered.
function TestNonStringKey(key) {
handler.enumerate = function(target) {
function* keys() { yield key; }
return keys();
}
assertThrows("for (var k in proxy) {}", TypeError);
}
TestNonStringKey(1);
TestNonStringKey(3.14);
TestNonStringKey(Symbol("foo"));
TestNonStringKey({bad: "value"});
TestNonStringKey(null);
TestNonStringKey(undefined);
TestNonStringKey(true);
(function testProtoProxyEnumerate() {
var keys = ['a', 'b', 'c', 'd'];
var handler = {
enumerate() { return keys[Symbol.iterator]() },
has(target, key) { return false }
};
var proxy = new Proxy({}, handler);
var seen_keys = [];
for (var i in proxy) {
seen_keys.push(i);
}
assertEquals([], seen_keys);
handler.has = function(target, key) { return true };
for (var i in proxy) {
seen_keys.push(i);
}
assertEquals(keys, seen_keys);
o = {__proto__:proxy};
handler.has = function(target, key) { return false };
seen_keys = [];
for (var i in o) {
seen_keys.push(i);
}
assertEquals([], seen_keys);
handler.has = function(target, key) { return true };
seen_keys = [];
for (var i in o) {
seen_keys.push(i);
}
assertEquals(keys, seen_keys);
})();
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