es.typed-array.sort.js

'use strict';
var ArrayBufferViewCore = require('../internals/array-buffer-view-core');
var global = require('../internals/global');
var fails = require('../internals/fails');
var aFunction = require('../internals/a-function');
var toLength = require('../internals/to-length');
var internalSort = require('../internals/array-sort');
var FF = require('../internals/engine-ff-version');
var IE_OR_EDGE = require('../internals/engine-is-ie-or-edge');
var V8 = require('../internals/engine-v8-version');
var WEBKIT = require('../internals/engine-webkit-version');

var aTypedArray = ArrayBufferViewCore.aTypedArray;
var exportTypedArrayMethod = ArrayBufferViewCore.exportTypedArrayMethod;
var Uint16Array = global.Uint16Array;
var nativeSort = Uint16Array && Uint16Array.prototype.sort;

// WebKit
var ACCEPT_INCORRECT_ARGUMENTS = !!nativeSort && !fails(function () {
  var array = new Uint16Array(2);
  array.sort(null);
  array.sort({});
});

var STABLE_SORT = !!nativeSort && !fails(function () {
  // feature detection can be too slow, so check engines versions
  if (V8) return V8 < 74;
  if (FF) return FF < 67;
  if (IE_OR_EDGE) return true;
  if (WEBKIT) return WEBKIT < 602;

  var array = new Uint16Array(516);
  var expected = Array(516);
  var index, mod;

  for (index = 0; index < 516; index++) {
    mod = index % 4;
    array[index] = 515 - index;
    expected[index] = index - 2 * mod + 3;
  }

  array.sort(function (a, b) {
    return (a / 4 | 0) - (b / 4 | 0);
  });

  for (index = 0; index < 516; index++) {
    if (array[index] !== expected[index]) return true;
  }
});

var getSortCompare = function (comparefn) {
  return function (x, y) {
    if (comparefn !== undefined) return +comparefn(x, y) || 0;
    // eslint-disable-next-line no-self-compare -- NaN check
    if (y !== y) return -1;
    // eslint-disable-next-line no-self-compare -- NaN check
    if (x !== x) return 1;
    if (x === 0 && y === 0) return 1 / x > 0 && 1 / y < 0 ? 1 : -1;
    return x > y;
  };
};

// `%TypedArray%.prototype.sort` method
// https://tc39.es/ecma262/#sec-%typedarray%.prototype.sort
exportTypedArrayMethod('sort', function sort(comparefn) {
  var array = this;
  if (comparefn !== undefined) aFunction(comparefn);
  if (STABLE_SORT) return nativeSort.call(array, comparefn);

  aTypedArray(array);
  var arrayLength = toLength(array.length);
  var items = Array(arrayLength);
  var index;

  for (index = 0; index < arrayLength; index++) {
    items[index] = array[index];
  }

  items = internalSort(array, getSortCompare(comparefn));

  for (index = 0; index < arrayLength; index++) {
    array[index] = items[index];
  }

  return array;
}, !STABLE_SORT || ACCEPT_INCORRECT_ARGUMENTS);