v8/src/proxy.js

210 lines
6.4 KiB
JavaScript

// Copyright 2011 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.
"use strict";
// This file relies on the fact that the following declaration has been made
// in runtime.js:
// var $Object = global.Object;
var $Proxy = new $Object();
// -------------------------------------------------------------------
function ProxyCreate(handler, proto) {
if (!IS_SPEC_OBJECT(handler))
throw MakeTypeError("handler_non_object", ["create"])
if (IS_UNDEFINED(proto))
proto = null
else if (!(IS_SPEC_OBJECT(proto) || proto === null))
throw MakeTypeError("proto_non_object", ["create"])
return %CreateJSProxy(handler, proto)
}
function ProxyCreateFunction(handler, callTrap, constructTrap) {
if (!IS_SPEC_OBJECT(handler))
throw MakeTypeError("handler_non_object", ["create"])
if (!IS_SPEC_FUNCTION(callTrap))
throw MakeTypeError("trap_function_expected", ["createFunction", "call"])
if (IS_UNDEFINED(constructTrap)) {
constructTrap = DerivedConstructTrap(callTrap)
} else if (IS_SPEC_FUNCTION(constructTrap)) {
// Make sure the trap receives 'undefined' as this.
var construct = constructTrap
constructTrap = function() {
return %Apply(construct, void 0, arguments, 0, %_ArgumentsLength());
}
} else {
throw MakeTypeError("trap_function_expected",
["createFunction", "construct"])
}
return %CreateJSFunctionProxy(
handler, callTrap, constructTrap, $Function.prototype)
}
// -------------------------------------------------------------------
function SetUpProxy() {
%CheckIsBootstrapping()
global.Proxy = $Proxy;
// Set up non-enumerable properties of the Proxy object.
InstallFunctions($Proxy, DONT_ENUM, [
"create", ProxyCreate,
"createFunction", ProxyCreateFunction
])
}
SetUpProxy();
// -------------------------------------------------------------------
// Proxy Builtins
function DerivedConstructTrap(callTrap) {
return function() {
var proto = this.prototype
if (!IS_SPEC_OBJECT(proto)) proto = $Object.prototype
var obj = { __proto__: proto };
var result = %Apply(callTrap, obj, arguments, 0, %_ArgumentsLength());
return IS_SPEC_OBJECT(result) ? result : obj
}
}
function DelegateCallAndConstruct(callTrap, constructTrap) {
return function() {
return %Apply(%_IsConstructCall() ? constructTrap : callTrap,
this, arguments, 0, %_ArgumentsLength())
}
}
function DerivedGetTrap(receiver, name) {
var desc = this.getPropertyDescriptor(name)
if (IS_UNDEFINED(desc)) { return desc }
if ('value' in desc) {
return desc.value
} else {
if (IS_UNDEFINED(desc.get)) { return desc.get }
// The proposal says: desc.get.call(receiver)
return %_CallFunction(receiver, desc.get)
}
}
function DerivedSetTrap(receiver, name, val) {
var desc = this.getOwnPropertyDescriptor(name)
if (desc) {
if ('writable' in desc) {
if (desc.writable) {
desc.value = val
this.defineProperty(name, desc)
return true
} else {
return false
}
} else { // accessor
if (desc.set) {
// The proposal says: desc.set.call(receiver, val)
%_CallFunction(receiver, val, desc.set)
return true
} else {
return false
}
}
}
desc = this.getPropertyDescriptor(name)
if (desc) {
if ('writable' in desc) {
if (desc.writable) {
// fall through
} else {
return false
}
} else { // accessor
if (desc.set) {
// The proposal says: desc.set.call(receiver, val)
%_CallFunction(receiver, val, desc.set)
return true
} else {
return false
}
}
}
this.defineProperty(name, {
value: val,
writable: true,
enumerable: true,
configurable: true});
return true;
}
function DerivedHasTrap(name) {
return !!this.getPropertyDescriptor(name)
}
function DerivedHasOwnTrap(name) {
return !!this.getOwnPropertyDescriptor(name)
}
function DerivedKeysTrap() {
var names = this.getOwnPropertyNames()
var enumerableNames = []
for (var i = 0, count = 0; i < names.length; ++i) {
var name = names[i]
if (IS_SYMBOL(name)) continue
var desc = this.getOwnPropertyDescriptor(TO_STRING_INLINE(name))
if (!IS_UNDEFINED(desc) && desc.enumerable) {
enumerableNames[count++] = names[i]
}
}
return enumerableNames
}
function DerivedEnumerateTrap() {
var names = this.getPropertyNames()
var enumerableNames = []
for (var i = 0, count = 0; i < names.length; ++i) {
var name = names[i]
if (IS_SYMBOL(name)) continue
var desc = this.getPropertyDescriptor(TO_STRING_INLINE(name))
if (!IS_UNDEFINED(desc) && desc.enumerable) {
enumerableNames[count++] = names[i]
}
}
return enumerableNames
}
function ProxyEnumerate(proxy) {
var handler = %GetHandler(proxy)
if (IS_UNDEFINED(handler.enumerate)) {
return %Apply(DerivedEnumerateTrap, handler, [], 0, 0)
} else {
return ToNameArray(handler.enumerate(), "enumerate", false)
}
}