just-add-juice/resources/scripts/polyfills/array-protoype-includes.js

A responsive frontend framework with modular components.

/*  =========================================================================
    APPLICATION -> POLYFILL -> ARRAY PROTOTYPE INCLUDES
    ========================================================================= */

/**
 * Array.prototype.includes polyfill.
 * @author Kevin Latusinski (kevlatus) <https://github.com/kevlatus/polyfill-array-includes>
 */
(function() {
    if (!Array.prototype.includes) {
        console.info('Polyfill: Array.prototype.includes');

        Object.defineProperty(Array.prototype, 'includes', {
            value: function (searchElement, fromIndex) {
                if (this == null) {
                    throw new TypeError('"this" is null or not defined');
                }

                var o = Object(this);
                var len = o.length >>> 0;

                if (len === 0) {
                    return false;
                }

                var n = fromIndex | 0;

                var k = Math.max(n >= 0 ? n : len - Math.abs(n), 0);

                function sameValueZero(x, y) {
                    return x === y || (typeof x === 'number' && typeof y === 'number' && isNaN(x) && isNaN(y));
                }

                while (k < len) {
                    if (sameValueZero(o[k], searchElement)) {
                        return true;
                    }

                    k++;
                }

                return false;
            }
        });
    }
})();