Utility Class

ES6 TIP: Create utility functions by using static methods, used without instantiating their class.

class SuperTools {
  static hasClass(elm, classN) {
    return new RegExp('(\\s|^)' + classN + '(\\s|$)').test(elm.classN);
  }
  static getCssProperty(elm, prop) {
    return window.getComputedStyle(elm, null).getPropertyValue(prop);
  }
}

SuperTools.hasClass(elm, 'class-name');