var global = require('../internals/global');
var fails = require('../internals/fails');
var uncurryThis = require('../internals/function-uncurry-this');
var toString = require('../internals/to-string');
var trim = require('../internals/string-trim').trim;
var whitespaces = require('../internals/whitespaces');

var $parseInt = global.parseInt;
var Symbol = global.Symbol;
var ITERATOR = Symbol && Symbol.iterator;
var hex = /^[+-]?0x/i;
var exec = uncurryThis(hex.exec);
var FORCED = $parseInt(whitespaces + '08') !== 8 || $parseInt(whitespaces + '0x16') !== 22
  // MS Edge 18- broken with boxed symbols
  || (ITERATOR && !fails(function () { $parseInt(Object(ITERATOR)); }));

// `parseInt` method
// https://tc39.es/ecma262/#sec-parseint-string-radix
module.exports = FORCED ? function parseInt(string, radix) {
  var S = trim(toString(string));
  return $parseInt(S, (radix >>> 0) || (exec(hex, S) ? 16 : 10));
} : $parseInt;