getSymbolDescription.js
1.15 KB
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'use strict';
var GetIntrinsic = require('../GetIntrinsic');
var callBound = require('./callBound');
var $SyntaxError = GetIntrinsic('%SyntaxError%');
var getGlobalSymbolDescription = GetIntrinsic('%Symbol.keyFor%', true);
var thisSymbolValue = callBound('%Symbol.prototype.valueOf%', true);
var symToStr = callBound('Symbol.prototype.toString', true);
var getInferredName = require('./getInferredName');
/* eslint-disable consistent-return */
module.exports = callBound('%Symbol.prototype.description%', true) || function getSymbolDescription(symbol) {
if (!thisSymbolValue) {
throw new $SyntaxError('Symbols are not supported in this environment');
}
// will throw if not a symbol primitive or wrapper object
var sym = thisSymbolValue(symbol);
if (getInferredName) {
var name = getInferredName(sym);
if (name === '') { return; }
return name.slice(1, -1); // name.slice('['.length, -']'.length);
}
var desc;
if (getGlobalSymbolDescription) {
desc = getGlobalSymbolDescription(sym);
if (typeof desc === 'string') {
return desc;
}
}
desc = symToStr(sym).slice(7, -1); // str.slice('Symbol('.length, -')'.length);
if (desc) {
return desc;
}
};