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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.
(function(global, utils) {
"use strict";
%CheckIsBootstrapping();
// -------------------------------------------------------------------
// Imports
var GlobalObject = global.Object;
var GlobalSymbol = global.Symbol;
var hasInstanceSymbol = utils.ImportNow("has_instance_symbol");
var isConcatSpreadableSymbol =
utils.ImportNow("is_concat_spreadable_symbol");
var isRegExpSymbol = utils.ImportNow("is_regexp_symbol");
var iteratorSymbol = utils.ImportNow("iterator_symbol");
var ObjectGetOwnPropertyKeys;
var toPrimitiveSymbol = utils.ImportNow("to_primitive_symbol");
var toStringTagSymbol = utils.ImportNow("to_string_tag_symbol");
var unscopablesSymbol = utils.ImportNow("unscopables_symbol");
utils.Import(function(from) {
ObjectGetOwnPropertyKeys = from.ObjectGetOwnPropertyKeys;
});
// -------------------------------------------------------------------
// 19.4.3.4 Symbol.prototype [ @@toPrimitive ] ( hint )
function SymbolToPrimitive(hint) {
if (!(IS_SYMBOL(this) || IS_SYMBOL_WRAPPER(this))) {
throw MakeTypeError(kIncompatibleMethodReceiver,
"Symbol.prototype [ @@toPrimitive ]", this);
}
return %_ValueOf(this);
}
function SymbolToString() {
if (!(IS_SYMBOL(this) || IS_SYMBOL_WRAPPER(this))) {
throw MakeTypeError(kIncompatibleMethodReceiver,
"Symbol.prototype.toString", this);
}
return %SymbolDescriptiveString(%_ValueOf(this));
}
function SymbolValueOf() {
if (!(IS_SYMBOL(this) || IS_SYMBOL_WRAPPER(this))) {
throw MakeTypeError(kIncompatibleMethodReceiver,
"Symbol.prototype.valueOf", this);
}
return %_ValueOf(this);
}
function SymbolFor(key) {
key = TO_STRING(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(kSymbolKeyFor, symbol);
return %SymbolRegistry().keyFor[symbol];
}
// ES6 19.1.2.8
function ObjectGetOwnPropertySymbols(obj) {
obj = TO_OBJECT(obj);
// TODO(arv): Proxies use a shared trap for String and Symbol keys.
return ObjectGetOwnPropertyKeys(obj, PROPERTY_ATTRIBUTES_STRING);
}
// -------------------------------------------------------------------
%FunctionSetPrototype(GlobalSymbol, new GlobalObject());
utils.InstallConstants(GlobalSymbol, [
// TODO(rossberg): expose when implemented.
// "hasInstance", hasInstanceSymbol,
// "isConcatSpreadable", isConcatSpreadableSymbol,
// "isRegExp", isRegExpSymbol,
"iterator", iteratorSymbol,
"toPrimitive", toPrimitiveSymbol,
// TODO(dslomov, caitp): Currently defined in harmony-tostring.js ---
// Move here when shipping
// "toStringTag", toStringTagSymbol,
"unscopables", unscopablesSymbol,
]);
utils.InstallFunctions(GlobalSymbol, DONT_ENUM, [
"for", SymbolFor,
"keyFor", SymbolKeyFor
]);
%AddNamedProperty(
GlobalSymbol.prototype, "constructor", GlobalSymbol, DONT_ENUM);
%AddNamedProperty(
GlobalSymbol.prototype, toStringTagSymbol, "Symbol", DONT_ENUM | READ_ONLY);
utils.InstallFunctions(GlobalSymbol.prototype, DONT_ENUM | READ_ONLY, [
toPrimitiveSymbol, SymbolToPrimitive
]);
utils.InstallFunctions(GlobalSymbol.prototype, DONT_ENUM, [
"toString", SymbolToString,
"valueOf", SymbolValueOf
]);
utils.InstallFunctions(GlobalObject, DONT_ENUM, [
"getOwnPropertySymbols", ObjectGetOwnPropertySymbols
]);
// -------------------------------------------------------------------
// Exports
utils.Export(function(to) {
to.SymbolToString = SymbolToString;
})
})
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