Autogrow Textarea with jQuery

jQuery.textAutoGrow.js

// MIT Licence (MIT)
// Copyright (c) 2015 - Mokhamad Rofiudin
// inspired by Facebook Textarea
// Based on code here http://github.com/jackmoore/autosize
// The Magic Sauce : http://stackoverflow.com/a/3238543/4711810

// To Angular Go To Here https://gist.github.com/mrofi/e6a8656be9705652ff1f


(function($) {
    $.fn.autogrow = function() {
        return this.each(function() {
            var textarea = this;
            textarea.lineHeight = parseInt($(textarea).css("line-height"), 3);
            $(textarea).data('oldValue', textarea.value);
            $.fn.autogrow.sizeDown(textarea);
            $(textarea).focus(function() {
                textarea.interval = setInterval(function() {
                    if ($(textarea).data('oldValue').length < textarea.value.length) {
                      $.fn.autogrow.sizeUp(textarea);
                    } else if ($(textarea).data('oldValue').length > textarea.value.length) {
                      $.fn.autogrow.sizeDown(textarea);
                    }
                   $(textarea).data('oldValue', textarea.value);
                }, 20);
            }).blur(function() {
                clearInterval(textarea.interval);
            });
        });
    };
    $.fn.autogrow.sizeUp = function(textarea) {
        while(textarea.clientHeight < textarea.scrollHeight){
          var height = textarea.clientHeight + textarea.lineHeight;
          $(textarea).css("height", height);
        }
    };
    $.fn.autogrow.sizeDown = function(textarea) {
        do {
          var height = textarea.clientHeight - textarea.lineHeight;
          $(textarea).css("height", height);
        } while(textarea.clientHeight >= textarea.scrollHeight)
          $.fn.autogrow.sizeUp(textarea);
    };
})(jQuery);

// Take this code in the wild
$('textarea').autogrow();

// See in the real world