multiply.js 848 B

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  1. 'use strict';
  2. var GetIntrinsic = require('get-intrinsic');
  3. var $TypeError = GetIntrinsic('%TypeError%');
  4. var isNaN = require('../../helpers/isNaN');
  5. var Type = require('../Type');
  6. // https://262.ecma-international.org/11.0/#sec-numeric-types-number-multiply
  7. module.exports = function NumberMultiply(x, y) {
  8. if (Type(x) !== 'Number' || Type(y) !== 'Number') {
  9. throw new $TypeError('Assertion failed: `x` and `y` arguments must be Numbers');
  10. }
  11. if (isNaN(x) || isNaN(y) || (x === 0 && !isFinite(y)) || (!isFinite(x) && y === 0)) {
  12. return NaN;
  13. }
  14. if (!isFinite(x) && !isFinite(y)) {
  15. return x === y ? Infinity : -Infinity;
  16. }
  17. if (!isFinite(x) && y !== 0) {
  18. return x > 0 ? Infinity : -Infinity;
  19. }
  20. if (!isFinite(y) && x !== 0) {
  21. return y > 0 ? Infinity : -Infinity;
  22. }
  23. // shortcut for the actual spec mechanics
  24. return x * y;
  25. };