es5.js 1.7 KB

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  1. 'use strict';
  2. var toStr = Object.prototype.toString;
  3. var isPrimitive = require('./helpers/isPrimitive');
  4. var isCallable = require('is-callable');
  5. /** @type {{ [k in `[[${string}]]`]: (O: { toString?: unknown, valueOf?: unknown }, actualHint?: StringConstructor | NumberConstructor) => null | undefined | string | symbol | number | boolean | bigint; }} */
  6. // http://ecma-international.org/ecma-262/5.1/#sec-8.12.8
  7. var ES5internalSlots = {
  8. '[[DefaultValue]]': function (O) {
  9. var actualHint;
  10. if (arguments.length > 1) {
  11. actualHint = arguments[1];
  12. } else {
  13. actualHint = toStr.call(O) === '[object Date]' ? String : Number;
  14. }
  15. if (actualHint === String || actualHint === Number) {
  16. /** @type {('toString' | 'valueOf')[]} */
  17. var methods = actualHint === String ? ['toString', 'valueOf'] : ['valueOf', 'toString'];
  18. var value, i;
  19. for (i = 0; i < methods.length; ++i) {
  20. var method = methods[i];
  21. if (isCallable(O[method])) {
  22. // eslint-disable-next-line no-extra-parens
  23. value = /** @type {Function} */ (O[method])();
  24. if (isPrimitive(value)) {
  25. return value;
  26. }
  27. }
  28. }
  29. throw new TypeError('No default value');
  30. }
  31. throw new TypeError('invalid [[DefaultValue]] hint supplied');
  32. }
  33. };
  34. /** @type {import('./es5')} */
  35. // http://ecma-international.org/ecma-262/5.1/#sec-9.1
  36. module.exports = function ToPrimitive(input) {
  37. if (isPrimitive(input)) {
  38. return input;
  39. }
  40. if (arguments.length > 1) {
  41. // eslint-disable-next-line no-extra-parens
  42. return ES5internalSlots['[[DefaultValue]]'](/** @type {object} */ (input), arguments[1]);
  43. }
  44. // eslint-disable-next-line no-extra-parens
  45. return ES5internalSlots['[[DefaultValue]]'](/** @type {object} */ (input));
  46. };