source: webkit/trunk/JavaScriptCore/runtime/JSVariableObject.cpp@ 47780

Last change on this file since 47780 was 47780, checked in by [email protected], 16 years ago

[ES5] Implement getOwnPropertyDescriptor
https://bugs.webkit.org/show_bug.cgi?id=28724

Reviewed by Gavin Barraclough.

JavaScriptCore:
Implement the core runtime support for getOwnPropertyDescriptor.
This adds a virtual getOwnPropertyDescriptor method to every class
that implements getOwnPropertySlot that shadows the behaviour of
getOwnPropertySlot. The alternative would be to make getOwnPropertySlot
(or PropertySlots in general) provide property attribute information,
but quick testing showed this to be a regression.

WebCore:
Implement the WebCore side of getOwnPropertyDescriptor. This
requires a custom implementation of getOwnPropertyDescriptor
for every class with a custom implementation of getOwnPropertySlot.

The bindings generator has been updated to generate appropriate
versions of getOwnPropertyDescriptor for the general case where
a custom getOwnPropertyDescriptor is not needed. ES5 is vague
about how getOwnPropertyDescriptor should work in the context of
"host" functions with polymorphic GetOwnProperty, so it seems
okay that occasionally we "guess" what attributes -- eg. determining
whether a property is writable.

Test: fast/js/getOwnPropertyDescriptor.html

  • Property svn:eol-style set to native
File size: 3.1 KB
Line 
1/*
2 * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14 * its contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include "config.h"
30#include "JSVariableObject.h"
31
32#include "PropertyNameArray.h"
33#include "PropertyDescriptor.h"
34
35namespace JSC {
36
37bool JSVariableObject::deleteProperty(ExecState* exec, const Identifier& propertyName)
38{
39 if (symbolTable().contains(propertyName.ustring().rep()))
40 return false;
41
42 return JSObject::deleteProperty(exec, propertyName);
43}
44
45void JSVariableObject::getPropertyNames(ExecState* exec, PropertyNameArray& propertyNames)
46{
47 SymbolTable::const_iterator end = symbolTable().end();
48 for (SymbolTable::const_iterator it = symbolTable().begin(); it != end; ++it) {
49 if (!(it->second.getAttributes() & DontEnum))
50 propertyNames.add(Identifier(exec, it->first.get()));
51 }
52
53 JSObject::getPropertyNames(exec, propertyNames);
54}
55
56bool JSVariableObject::getPropertyAttributes(ExecState* exec, const Identifier& propertyName, unsigned& attributes) const
57{
58 SymbolTableEntry entry = symbolTable().get(propertyName.ustring().rep());
59 if (!entry.isNull()) {
60 attributes = entry.getAttributes() | DontDelete;
61 return true;
62 }
63 return JSObject::getPropertyAttributes(exec, propertyName, attributes);
64}
65
66bool JSVariableObject::isVariableObject() const
67{
68 return true;
69}
70
71bool JSVariableObject::symbolTableGet(const Identifier& propertyName, PropertyDescriptor& descriptor)
72{
73 SymbolTableEntry entry = symbolTable().inlineGet(propertyName.ustring().rep());
74 if (!entry.isNull()) {
75 descriptor.setDescriptor(registerAt(entry.getIndex()).jsValue(), entry.getAttributes() | DontDelete);
76 return true;
77 }
78 return false;
79}
80
81} // namespace JSC
Note: See TracBrowser for help on using the repository browser.