v8/test/mjsunit/harmony/object-spread-basic.js
gsathya a40b7172fe [ESnext] Implement Object spread
This patch adds parsing of spread object property.

-- Changes ParsePropertyName to parse Token::ELLIPSIS.
-- Throws if rest is encountered by setting a pattern error.
-- Adds a new PropertyKind enum (SPREAD)
-- Adds a new ObjectLiteralProperty::kind (SPREAD)
-- Adds a new harmony-object-spread flag and protects the parser code
with it.
-- Adds a new runtime function called CopyDataProperties
-- Does not add any support for this feature in fullcodegen.
-- Ignition calls out to a runtime function CopyDataProperties to
perform spread operation.
-- Move FastAssign from builtins-objects.cc to objects.cc
-- Refactor Builtin_ObjectAssign to use SetOrCopyDataProperties

Object rest will be implemented in a follow on patch.

BUG=v8:5549

Review-Url: https://codereview.chromium.org/2606833002
Cr-Commit-Position: refs/heads/master@{#42102}
2017-01-05 23:44:25 +00:00

112 lines
2.7 KiB
JavaScript

// Copyright 2016 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-object-spread
var x = {a: 1};
var y = { ...x};
assertEquals(x, y);
assertEquals({}, y = { ...{} } );
assertEquals({}, y = { ...undefined });
assertEquals({}, y = { ...null });
assertEquals({}, y = { ...1 });
assertEquals({0: 'f', 1: 'o', 2: 'o'}, y = { ...'foo' });
assertEquals({0: 0, 1: 1}, y = { ...[0, 1] });
assertEquals({}, { ...new Proxy({}, {}) });
assertEquals({a: 2}, y = { ...x, a: 2 });
assertEquals({a: 1, b: 1}, y = { ...x, b: 1 });
assertEquals({a: 1}, y = { a: 2, ...x });
assertEquals({a: 1, b: 1}, y = { a:2, ...x, b: 1 });
assertEquals({a: 3}, y = { a: 2, ...x, a: 3 });
var z = { b: 1}
assertEquals({a: 1, b: 1}, y = { ...x, ...z });
assertEquals({a: 1, b: 1}, y = { a: 2, ...x, ...z });
assertEquals({a: 1, b: 1}, y = { b: 2, ...z, ...x });
assertEquals({a: 1, b: 1}, y = { a: 1, ...x, b: 2, ...z });
assertEquals({a: 1, b: 2}, y = { a: 1, ...x, ...z, b: 2 });
assertEquals({a: 2, b: 2}, y = { ...x, ...z, a:2, b: 2 });
var x = {}
Object.defineProperty(x, 'a', {
enumerable: false,
configurable: false,
writable: false,
value: 1
});
assertEquals({}, { ...x });
var x = {}
Object.defineProperty(x, 'a', {
enumerable: true,
configurable: false,
writable: false,
value: 1
});
var y = { ...x };
var prop = Object.getOwnPropertyDescriptor(y, 'a');
assertEquals(prop.value, 1);
assertTrue(prop.enumerable);
assertTrue(prop.configurable);
assertTrue(prop.writable);
var x = { __proto__: z }
assertEquals({}, { ...x });
var x = {
get a() { return 1; },
set a(_) { assertUnreachable("setter called"); },
};
assertEquals({ a: 1 }, y = { ...x });
var x = {
method() { return 1; },
};
assertEquals(x, y = { ...x });
var x = {
*gen() { return {value: 1, done: true} ; },
};
assertEquals(x, y = { ...x });
var x = {
get a() { throw new Error(); },
};
assertThrows(() => { y = { ...x } });
var p = new Proxy({}, {
ownKeys() { throw new Error(); }
});
assertThrows(() => { y = { ...p } });
var p = new Proxy({}, {
ownKeys() { [1]; },
get() { throw new Error(); }
});
assertThrows(() => { y = { ...p } });
var p = new Proxy({}, {
ownKeys() { [1]; },
getOwnPropertyDescriptor() { throw new Error(); }
});
assertThrows(() => { y = { ...p } });
var p = new Proxy(z, {
ownKeys() { return Object.keys(z); },
get(_, prop) { return z[prop]; },
getOwnPropertyDescriptor(_, prop) {
return Object.getOwnPropertyDescriptor(z, prop);
},
});
assertEquals(z, y = { ...p });
var x = { a:1 };
assertEquals(x, y = { set a(_) { throw new Error(); }, ...x });
var x = { a:1 };
assertEquals(x, y = { get a() { throw new Error(); }, ...x });