implementation.js

'use strict';

var ES = require('es-abstract/es6');
var $isNaN = Number.isNaN || function isNaN(a) {
	return a !== a;
};
var $isFinite = Number.isFinite || function isFinite(n) {
	return typeof n === 'number' && global.isFinite(n);
};
var indexOf = Array.prototype.indexOf;

module.exports = function includes(searchElement) {
	var fromIndex = arguments.length > 1 ? ES.ToInteger(arguments[1]) : 0;
	if (indexOf && !$isNaN(searchElement) && $isFinite(fromIndex) && typeof searchElement !== 'undefined') {
		return indexOf.apply(this, arguments) > -1;
	}

	var O = ES.ToObject(this);
	var length = ES.ToLength(O.length);
	if (length === 0) {
		return false;
	}
	var k = fromIndex >= 0 ? fromIndex : Math.max(0, length + fromIndex);
	while (k < length) {
		if (ES.SameValueZero(searchElement, O[k])) {
			return true;
		}
		k += 1;
	}
	return false;
};