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// Copyright 2017 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: --allow-natives-syntax
// Ensure empty keys are handled properly
(function() {
const a = {};
let k = Object.keys(a);
%HeapObjectVerify(k);
assertEquals(0, k.length);
})();
// Ensure non-enumerable keys are handled properly
(function() {
const a = {};
Object.defineProperty(a, 'x', {
value: 1,
enumerable: false
});
let k = Object.keys(a);
%HeapObjectVerify(k);
assertEquals(0, k.length);
a.y = 2;
k = Object.keys(a);
%HeapObjectVerify(k);
assertEquals(1, k.length);
})();
// Ensure that mutation of the Object.keys result doesn't affect the
// enumeration cache for fast-mode objects.
(function() {
const a = {x:1, y:2};
let k = Object.keys(a);
%HeapObjectVerify(k);
assertEquals(2, k.length);
assertEquals("x", k[0]);
assertEquals("y", k[1]);
k[0] = "y";
k[1] = "x";
k = Object.keys(a);
assertEquals(2, k.length);
assertEquals("x", k[0]);
assertEquals("y", k[1]);
})();
// Ensure that the copy-on-write keys are handled properly, even in
// the presence of Symbols.
(function() {
const s = Symbol();
const a = {[s]: 1};
let k = Object.keys(a);
%HeapObjectVerify(k);
assertEquals(0, k.length);
k.shift();
assertEquals(0, k.length);
})();
// Ensure we invoke all steps on proxies.
(function ObjectKeysProxy() {
let log = [];
let result = Object.keys(new Proxy({}, {
ownKeys(target) {
log.push('ownKeys');
return ['a', 'b', 'c'];
},
getOwnPropertyDescriptor(target, key) {
log.push('getOwnPropertyDescriptor-' + key);
if (key === 'b') return {enumerable: false, configurable: true};
return {enumerable: true, configurable: true};
}
}));
assertEquals(['a', 'c'], result);
assertEquals(
[
'ownKeys', 'getOwnPropertyDescriptor-a', 'getOwnPropertyDescriptor-b',
'getOwnPropertyDescriptor-c'
],
log);
// Test normal target.
log = [];
let target = {a: 1, b: 1, c: 1};
let handler = {
getOwnPropertyDescriptor(target, key) {
log.push('getOwnPropertyDescriptor-' + key);
if (key === 'b') return {enumerable: false, configurable: true};
return {enumerable: true, configurable: true};
}
};
result = Object.keys(new Proxy(target, handler));
assertEquals(['a', 'c'], result);
assertEquals(
[
'getOwnPropertyDescriptor-a', 'getOwnPropertyDescriptor-b',
'getOwnPropertyDescriptor-c'
],
log);
// Test trap invocation with non-enumerable target properties.
log = [];
target = Object.create(Object.prototype, {
a: {enumerable: true, configurable: true},
b: {enumerable: false, configurable: true},
c: {enumerable: true, configurable: true}
});
result = Object.keys(new Proxy(target, handler));
assertEquals(['a', 'c'], result);
assertEquals(
[
'getOwnPropertyDescriptor-a', 'getOwnPropertyDescriptor-b',
'getOwnPropertyDescriptor-c'
],
log);
})();
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