const objectProto = Object.prototype const hasOwnProperty = objectProto.hasOwnProperty const toString = objectProto.toString const symToStringTag = typeof Symbol != 'undefined' ? Symbol.toStringTag : undefined /** * The base implementation of `getTag` without fallbacks for buggy environments. * * @private * @param {*} value The value to query. * @returns {string} Returns the `toStringTag`. */ function baseGetTag(value) { if (value == null) { return value === undefined ? '[object Undefined]' : '[object Null]' } if (!(symToStringTag && symToStringTag in Object(value))) { return toString.call(value) } const isOwn = hasOwnProperty.call(value, symToStringTag) const tag = value[symToStringTag] let unmasked = false try { value[symToStringTag] = undefined unmasked = true } catch (e) {} const result = toString.call(value) if (unmasked) { if (isOwn) { value[symToStringTag] = tag } else { delete value[symToStringTag] } } return result } export default baseGetTag