isISIN.js 1.1 KB

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  1. "use strict";
  2. Object.defineProperty(exports, "__esModule", {
  3. value: true
  4. });
  5. exports.default = isISIN;
  6. var _assertString = _interopRequireDefault(require("./util/assertString"));
  7. function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
  8. var isin = /^[A-Z]{2}[0-9A-Z]{9}[0-9]$/;
  9. function isISIN(str) {
  10. (0, _assertString.default)(str);
  11. if (!isin.test(str)) {
  12. return false;
  13. }
  14. var checksumStr = str.replace(/[A-Z]/g, function (character) {
  15. return parseInt(character, 36);
  16. });
  17. var sum = 0;
  18. var digit;
  19. var tmpNum;
  20. var shouldDouble = true;
  21. for (var i = checksumStr.length - 2; i >= 0; i--) {
  22. digit = checksumStr.substring(i, i + 1);
  23. tmpNum = parseInt(digit, 10);
  24. if (shouldDouble) {
  25. tmpNum *= 2;
  26. if (tmpNum >= 10) {
  27. sum += tmpNum + 1;
  28. } else {
  29. sum += tmpNum;
  30. }
  31. } else {
  32. sum += tmpNum;
  33. }
  34. shouldDouble = !shouldDouble;
  35. }
  36. return parseInt(str.substr(str.length - 1), 10) === (10000 - sum) % 10;
  37. }
  38. module.exports = exports.default;
  39. module.exports.default = exports.default;