skill-assessment-app/app/assets/javascripts/textarea-limit.js

$(document).ready(function() {
  setTextAreaLimit();

  function setTextAreaLimit() {
    $.fn.extend({
      limiter: function(limit, elem) {
        $('textarea').on("keyup focus show", function() {
          setCount(this, elem);
        });

        function setCount(src, elem) {
          if(src !== undefined) {
            var chars = src.value.length;
            if (chars > limit) {
              src.value = src.value.substr(0, limit);
              chars = limit;
            }
            elem.html(limit - chars);
          }
        }
        setCount($(this)[0], elem);
      }
    });

    var elem = $(".chars span");
    $('textarea').limiter(1000, elem);
  }
});