I agree, included test with random array elements.

I have problems with the test case:

"Should work with complex expressions - Expected: 14, instead got: 13"

Could you give more information about the input of this test case ?

Yes, I updated the description, if anyone has better proposals on the description post here.

Exactly, I left out the final looping because this more like the homework for user.

True, actually I missed the second part of this kata which would be returning the sorted array. This exposes the problem, that the user can use any sorting algorithm's and I can not be sure if the bitwise operations were used or not.

Well I might change the kata description so that the solution also accepts all the UTF-8 characters, I think this would be better ?

Good point, added also the functionality to really compare the object content, previously I was using Test inspect function which makes objects to string and compares. This problem should be now solved.

Thank you, for your feedback added this in kata.