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// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-proxy-object-internal-methods-and-internal-slots-set-p-v-receiver
description: >
If "set" trap is missing, the call is properly forwarded to ordinary
[[Set]] that invokes [[GetOwnProperty]] and [[DefineOwnProperty]] methods
on receiver (that is a Proxy itself) every time it is called.
(integer index property name)
info: |
[[Set]] ( P, V, Receiver )
[...]
6. Let trap be ? GetMethod(handler, "set").
7. If trap is undefined, then
a. Return ? target.[[Set]](P, V, Receiver).
OrdinarySetWithOwnDescriptor ( O, P, V, Receiver, ownDesc )
[...]
3. If IsDataDescriptor(ownDesc) is true, then
[...]
c. Let existingDescriptor be ? Receiver.[[GetOwnProperty]](P).
d. If existingDescriptor is not undefined, then
[...]
iii. Let valueDesc be the PropertyDescriptor { [[Value]]: V }.
iv. Return ? Receiver.[[DefineOwnProperty]](P, valueDesc).
e. Else,
i. Assert: Receiver does not currently have a property P.
ii. Return ? CreateDataProperty(Receiver, P, V).
[...]
[[DefineOwnProperty]] ( P, Desc )
[...]
9. Let booleanTrapResult be ! ToBoolean(? Call(trap, handler, « target, P, descObj »)).
[...]
17. Return true.
features: [Proxy, Reflect]
includes: [compareArray.js]
---*/
var getOwnPropertyKeys = [];
var definePropertyKeys = [];
var p = new Proxy({
"0": null,
}, {
getOwnPropertyDescriptor: function(target, key) {
getOwnPropertyKeys.push(key);
return Reflect.getOwnPropertyDescriptor(target, key);
},
defineProperty: function(target, key, desc) {
definePropertyKeys.push(key);
return Reflect.defineProperty(target, key, desc);
},
});
p[0] = true;
p[0] = true;
p["0"] = true;
assert.compareArray(getOwnPropertyKeys, ["0", "0", "0"],
"getOwnPropertyDescriptor: key present on [[ProxyTarget]]");
assert.compareArray(definePropertyKeys, ["0", "0", "0"],
"defineProperty: key present on [[ProxyTarget]]");
getOwnPropertyKeys = [];
definePropertyKeys = [];
p[22] = false;
p["22"] = false;
p[22] = false;
assert.compareArray(getOwnPropertyKeys, ["22", "22", "22"],
"getOwnPropertyDescriptor: key absent on [[ProxyTarget]]");
assert.compareArray(definePropertyKeys, ["22", "22", "22"],
"defineProperty: key absent on [[ProxyTarget]]");
reportCompare(0, 0);