es.regexp.to-string.js 1.0 KB

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  1. 'use strict';
  2. var redefine = require('../internals/redefine');
  3. var anObject = require('../internals/an-object');
  4. var $toString = require('../internals/to-string');
  5. var fails = require('../internals/fails');
  6. var flags = require('../internals/regexp-flags');
  7. var TO_STRING = 'toString';
  8. var RegExpPrototype = RegExp.prototype;
  9. var nativeToString = RegExpPrototype[TO_STRING];
  10. var NOT_GENERIC = fails(function () { return nativeToString.call({ source: 'a', flags: 'b' }) != '/a/b'; });
  11. // FF44- RegExp#toString has a wrong name
  12. var INCORRECT_NAME = nativeToString.name != TO_STRING;
  13. // `RegExp.prototype.toString` method
  14. // https://tc39.es/ecma262/#sec-regexp.prototype.tostring
  15. if (NOT_GENERIC || INCORRECT_NAME) {
  16. redefine(RegExp.prototype, TO_STRING, function toString() {
  17. var R = anObject(this);
  18. var p = $toString(R.source);
  19. var rf = R.flags;
  20. var f = $toString(rf === undefined && R instanceof RegExp && !('flags' in RegExpPrototype) ? flags.call(R) : rf);
  21. return '/' + p + '/' + f;
  22. }, { unsafe: true });
  23. }