vowelCounter

QA.js

function getCount(str) {
  var vowelsCount = 0;
  
  strArr = str.split('');
  strArr.forEach(vowelCounter);
  return vowelsCount;

  // helper
  function vowelCounter(letter) {
    var vowels = ['a','e','i','o','u'];
    if( vowels.indexOf(letter) !== -1) vowelsCount++;
  }
}

console.log(getCount('abracadabra'));