• You "edited" the initial solution by removing everything. I would suggest you add at least the following code to make things clear:

    Array.prototype.numberOfOccurences = function(needle) {
      return 0;
    }
    

    Additionally, occurence should be written as occurrence with two "r": http://en.wiktionary.org/wiki/occurrence

    Finally, as part of an ongoing process to enhance the katas on codewars, could you maybe provide the user with an example test fixture and enhance your test cases to avoid cheating. At the moment, you have a number of test cases which expect a very specific return value. This is easy to cheat by returning constant values in a specific order. Maybe add a little randomness into your test cases?