debian-mirror-gitlab/core-js/internals/math-fround.js
2019-09-25 13:30:05 +05:30

26 lines
804 B
JavaScript

var sign = require('../internals/math-sign');
var abs = Math.abs;
var pow = Math.pow;
var EPSILON = pow(2, -52);
var EPSILON32 = pow(2, -23);
var MAX32 = pow(2, 127) * (2 - EPSILON32);
var MIN32 = pow(2, -126);
var roundTiesToEven = function (n) {
return n + 1 / EPSILON - 1 / EPSILON;
};
// `Math.fround` method implementation
// https://tc39.github.io/ecma262/#sec-math.fround
module.exports = Math.fround || function fround(x) {
var $abs = abs(x);
var $sign = sign(x);
var a, result;
if ($abs < MIN32) return $sign * roundTiesToEven($abs / MIN32 / EPSILON32) * MIN32 * EPSILON32;
a = (1 + EPSILON32 / EPSILON) * $abs;
result = a - (a - $abs);
// eslint-disable-next-line no-self-compare
if (result > MAX32 || result != result) return $sign * Infinity;
return $sign * result;
};