v8/test/mjsunit/get-own-property-descriptor.js
ricow@chromium.org 5058db86c4 Add support for getOwnPropertyDescriptor on array indices (fixes issue 599).
This fix adds support for retriving a property descriptor on elements. The
new version supports both fast and slow case elements. In the fast case
we always default configurable, writable, enumerable to true (we don't have
PropertyDetails for fast elements).

A few new tests are added to get-own-property-descriptor.js, I will
add a lot more to object-define-property when I add support for indices in
Object.defineProperty.


Review URL: http://codereview.chromium.org/2278002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4738 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2010-05-27 07:43:43 +00:00

106 lines
4.2 KiB
JavaScript

// Copyright 2010 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// This file only tests very simple descriptors that always have
// configurable, enumerable, and writable set to true.
// A range of more elaborate tests are performed in
// object-define-property.js
function get() { return x; }
function set(x) { this.x = x; }
var obj = {x: 1};
obj.__defineGetter__("accessor", get);
obj.__defineSetter__("accessor", set);
var a = new Array();
a[1] = 42;
obj[1] = 42;
var descIsData = Object.getOwnPropertyDescriptor(obj, 'x');
assertTrue(descIsData.enumerable);
assertTrue(descIsData.writable);
assertTrue(descIsData.configurable);
var descIsAccessor = Object.getOwnPropertyDescriptor(obj, 'accessor');
assertTrue(descIsAccessor.enumerable);
assertTrue(descIsAccessor.configurable);
assertTrue(descIsAccessor.get == get);
assertTrue(descIsAccessor.set == set);
var descIsNotData = Object.getOwnPropertyDescriptor(obj, 'not-x');
assertTrue(descIsNotData == undefined);
var descIsNotAccessor = Object.getOwnPropertyDescriptor(obj, 'not-accessor');
assertTrue(descIsNotAccessor == undefined);
var descArray = Object.getOwnPropertyDescriptor(a, '1');
assertTrue(descArray.enumerable);
assertTrue(descArray.configurable);
assertTrue(descArray.writable);
assertEquals(descArray.value, 42);
var descObjectElement = Object.getOwnPropertyDescriptor(obj, '1');
assertTrue(descObjectElement.enumerable);
assertTrue(descObjectElement.configurable);
assertTrue(descObjectElement.writable);
assertEquals(descObjectElement.value, 42);
// String objects.
var a = new String('foobar');
for (var i = 0; i < a.length; i++) {
var descStringObject = Object.getOwnPropertyDescriptor(a, i);
assertFalse(descStringObject.enumerable);
assertFalse(descStringObject.configurable);
assertFalse(descStringObject.writable);
assertEquals(descStringObject.value, a.substring(i, i+1));
}
// Support for additional attributes on string objects.
a.x = 42;
a[10] = 'foo';
var descStringProperty = Object.getOwnPropertyDescriptor(a, 'x');
assertTrue(descStringProperty.enumerable);
assertTrue(descStringProperty.configurable);
assertTrue(descStringProperty.writable);
assertEquals(descStringProperty.value, 42);
var descStringElement = Object.getOwnPropertyDescriptor(a, '10');
assertTrue(descStringElement.enumerable);
assertTrue(descStringElement.configurable);
assertTrue(descStringElement.writable);
assertEquals(descStringElement.value, 'foo');
// Test that elements in the prototype chain is not returned.
var proto = {};
proto[10] = 42;
var objWithProto = new Array();
objWithProto.prototype = proto;
objWithProto[0] = 'bar';
var descWithProto = Object.getOwnPropertyDescriptor(objWithProto, '10');
assertEquals(undefined, descWithProto);