'use strict';
+var global = require('../internals/global');
var isArray = require('../internals/is-array');
-var toLength = require('../internals/to-length');
+var lengthOfArrayLike = require('../internals/length-of-array-like');
var bind = require('../internals/function-bind-context');
+var TypeError = global.TypeError;
+
// `FlattenIntoArray` abstract operation
// https://tc39.github.io/proposal-flatMap/#sec-FlattenIntoArray
var flattenIntoArray = function (target, original, source, sourceLen, start, depth, mapper, thisArg) {
var targetIndex = start;
var sourceIndex = 0;
- var mapFn = mapper ? bind(mapper, thisArg, 3) : false;
- var element;
+ var mapFn = mapper ? bind(mapper, thisArg) : false;
+ var element, elementLen;
while (sourceIndex < sourceLen) {
if (sourceIndex in source) {
element = mapFn ? mapFn(source[sourceIndex], sourceIndex, original) : source[sourceIndex];
if (depth > 0 && isArray(element)) {
- targetIndex = flattenIntoArray(target, original, element, toLength(element.length), targetIndex, depth - 1) - 1;
+ elementLen = lengthOfArrayLike(element);
+ targetIndex = flattenIntoArray(target, original, element, elementLen, targetIndex, depth - 1) - 1;
} else {
if (targetIndex >= 0x1FFFFFFFFFFFFF) throw TypeError('Exceed the acceptable array length');
target[targetIndex] = element;