Clean CSS identifier from string

function.js

// In a perfect world, you'd never have to do this. Wish I lived in a perfect world.

/**
 * Convert a string to a usable class name
 * @param  {string} stringToConvert   String of text
 * @return {string}                   Usable class name
 */
function convertStringToClassName(stringToConvert) {
  if (typeof stringToConvert === 'string') {
    return stringToConvert.trim().replace(/[\s-_]+/g, '-').replace(/[^\w-]|^-|-$/g, '').replace(/-+(?=-)/, '').toLowerCase();
  }
};

Updated with @m4olivei's feedback