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// Copyright 2013 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.
// Expects following symbols to be set in the bootstrapper during genesis:
// - symbolHasInstance
// - symbolIsConcatSpreadable
// - symbolIsRegExp
// - symbolIterator
// - symbolToStringTag
// - symbolUnscopables
var $symbolToString;
(function() {
"use strict";
%CheckIsBootstrapping();
var GlobalArray = global.Array;
var GlobalObject = global.Object;
var GlobalSymbol = global.Symbol;
// -------------------------------------------------------------------
function SymbolConstructor(x) {
if (%_IsConstructCall()) {
throw MakeTypeError('not_constructor', ["Symbol"]);
}
// NOTE: Passing in a Symbol value will throw on ToString().
return %CreateSymbol(IS_UNDEFINED(x) ? x : ToString(x));
}
function SymbolToString() {
if (!(IS_SYMBOL(this) || IS_SYMBOL_WRAPPER(this))) {
throw MakeTypeError(
'incompatible_method_receiver', ["Symbol.prototype.toString", this]);
}
var description = %SymbolDescription(%_ValueOf(this));
return "Symbol(" + (IS_UNDEFINED(description) ? "" : description) + ")";
}
function SymbolValueOf() {
if (!(IS_SYMBOL(this) || IS_SYMBOL_WRAPPER(this))) {
throw MakeTypeError(
'incompatible_method_receiver', ["Symbol.prototype.valueOf", this]);
}
return %_ValueOf(this);
}
function SymbolFor(key) {
key = TO_STRING_INLINE(key);
var registry = %SymbolRegistry();
if (IS_UNDEFINED(registry.for[key])) {
var symbol = %CreateSymbol(key);
registry.for[key] = symbol;
registry.keyFor[symbol] = key;
}
return registry.for[key];
}
function SymbolKeyFor(symbol) {
if (!IS_SYMBOL(symbol)) throw MakeTypeError("not_a_symbol", [symbol]);
return %SymbolRegistry().keyFor[symbol];
}
// ES6 19.1.2.8
function ObjectGetOwnPropertySymbols(obj) {
obj = ToObject(obj);
// TODO(arv): Proxies use a shared trap for String and Symbol keys.
return ObjectGetOwnPropertyKeys(obj, PROPERTY_ATTRIBUTES_STRING);
}
//-------------------------------------------------------------------
%SetCode(GlobalSymbol, SymbolConstructor);
%FunctionSetPrototype(GlobalSymbol, new GlobalObject());
InstallConstants(GlobalSymbol, GlobalArray(
// TODO(rossberg): expose when implemented.
// "hasInstance", symbolHasInstance,
// "isConcatSpreadable", symbolIsConcatSpreadable,
// "isRegExp", symbolIsRegExp,
"iterator", symbolIterator,
// TODO(dslomov, caitp): Currently defined in harmony-tostring.js ---
// Move here when shipping
// "toStringTag", symbolToStringTag,
"unscopables", symbolUnscopables
));
InstallFunctions(GlobalSymbol, DONT_ENUM, GlobalArray(
"for", SymbolFor,
"keyFor", SymbolKeyFor
));
%AddNamedProperty(
GlobalSymbol.prototype, "constructor", GlobalSymbol, DONT_ENUM);
%AddNamedProperty(
GlobalSymbol.prototype, symbolToStringTag, "Symbol", DONT_ENUM | READ_ONLY);
InstallFunctions(GlobalSymbol.prototype, DONT_ENUM, GlobalArray(
"toString", SymbolToString,
"valueOf", SymbolValueOf
));
InstallFunctions(GlobalObject, DONT_ENUM, GlobalArray(
"getOwnPropertySymbols", ObjectGetOwnPropertySymbols
));
$symbolToString = SymbolToString;
})();
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