| // 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(global, utils) { |
| |
| "use strict"; |
| |
| %CheckIsBootstrapping(); |
| |
| // ------------------------------------------------------------------- |
| // Imports |
| |
| var GlobalObject = global.Object; |
| var GlobalSymbol = global.Symbol; |
| |
| var ObjectGetOwnPropertyKeys; |
| |
| utils.Import(function(from) { |
| ObjectGetOwnPropertyKeys = from.ObjectGetOwnPropertyKeys; |
| }); |
| |
| // ------------------------------------------------------------------- |
| |
| function SymbolConstructor(x) { |
| if (%_IsConstructCall()) throw MakeTypeError(kNotConstructor, "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(kIncompatibleMethodReceiver, |
| "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(kIncompatibleMethodReceiver, |
| "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(kSymbolKeyFor, 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()); |
| |
| utils.InstallConstants(GlobalSymbol, [ |
| // 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 |
| ]); |
| |
| utils.InstallFunctions(GlobalSymbol, DONT_ENUM, [ |
| "for", SymbolFor, |
| "keyFor", SymbolKeyFor |
| ]); |
| |
| %AddNamedProperty( |
| GlobalSymbol.prototype, "constructor", GlobalSymbol, DONT_ENUM); |
| %AddNamedProperty( |
| GlobalSymbol.prototype, symbolToStringTag, "Symbol", DONT_ENUM | READ_ONLY); |
| |
| utils.InstallFunctions(GlobalSymbol.prototype, DONT_ENUM, [ |
| "toString", SymbolToString, |
| "valueOf", SymbolValueOf |
| ]); |
| |
| utils.InstallFunctions(GlobalObject, DONT_ENUM, [ |
| "getOwnPropertySymbols", ObjectGetOwnPropertySymbols |
| ]); |
| |
| $symbolToString = SymbolToString; |
| |
| }) |