// `Symbol.prototype.description` getter // https://tc39.es/ecma262/#sec-symbol.prototype.description 'use strict'; var $ = require('../internals/export'); var DESCRIPTORS = require('../internals/descriptors'); var global = require('../internals/global'); var uncurryThis = require('../internals/function-uncurry-this'); var hasOwn = require('../internals/has-own-property'); var isCallable = require('../internals/is-callable'); var isPrototypeOf = require('../internals/object-is-prototype-of'); var toString = require('../internals/to-string'); var defineBuiltInAccessor = require('../internals/define-built-in-accessor'); var copyConstructorProperties = require('../internals/copy-constructor-properties'); var NativeSymbol = global.Symbol; var SymbolPrototype = NativeSymbol && NativeSymbol.prototype; if (DESCRIPTORS && isCallable(NativeSymbol) && (!('description' in SymbolPrototype) || // Safari 12 bug NativeSymbol().description !== undefined )) { var EmptyStringDescriptionStore = {}; // wrap Symbol constructor for correct work with undefined description var SymbolWrapper = function Symbol() { var description = arguments.length < 1 || arguments[0] === undefined ? undefined : toString(arguments[0]); var result = isPrototypeOf(SymbolPrototype, this) ? new NativeSymbol(description) // in Edge 13, String(Symbol(undefined)) === 'Symbol(undefined)' : description === undefined ? NativeSymbol() : NativeSymbol(description); if (description === '') EmptyStringDescriptionStore[result] = true; return result; }; copyConstructorProperties(SymbolWrapper, NativeSymbol); SymbolWrapper.prototype = SymbolPrototype; SymbolPrototype.constructor = SymbolWrapper; var NATIVE_SYMBOL = String(NativeSymbol('description detection')) === 'Symbol(description detection)'; var thisSymbolValue = uncurryThis(SymbolPrototype.valueOf); var symbolDescriptiveString = uncurryThis(SymbolPrototype.toString); var regexp = /^Symbol\((.*)\)[^)]+$/; var replace = uncurryThis(''.replace); var stringSlice = uncurryThis(''.slice); defineBuiltInAccessor(SymbolPrototype, 'description', { configurable: true, get: function description() { var symbol = thisSymbolValue(this); if (hasOwn(EmptyStringDescriptionStore, symbol)) return ''; var string = symbolDescriptiveString(symbol); var desc = NATIVE_SYMBOL ? stringSlice(string, 7, -1) : replace(string, regexp, '$1'); return desc === '' ? undefined : desc; } }); $({ global: true, constructor: true, forced: true }, { Symbol: SymbolWrapper }); }