// false -> Array#indexOf // true -> Array#includes var toIObject = require('./_to-iobject'); var toLength = require('./_to-length'); var toAbsoluteIndex = require('./_to-absolute-index'); module.exports = function (IS_INCLUDES) { return function ($this, el, fromIndex) { var O = toIObject($this); var length = toLength(O.length); var index = toAbsoluteIndex(fromIndex, length); var value; // Array#includes uses SameValueZero equality algorithm // eslint-disable-next-line no-self-compare if (IS_INCLUDES && el != el) while (length > index) { value = O[index++]; // eslint-disable-next-line no-self-compare if (value != value) return true; // Array#indexOf ignores holes, Array#includes - not } else for (;length > index; index++) if (IS_INCLUDES || index in O) { if (O[index] === el) return IS_INCLUDES || index || 0; } return !IS_INCLUDES && -1; }; };