ruby insertion sort

insertion_sort.rb

def insertion_sort(array)
  final = []
  final << array.shift 
    for i in array
      final_index = 0
      while final_index < final.length 
        if i <= final[final_index] 
          final.insert(final_index,i) 
          break  
        elsif final_index == final.length-1 
          final.insert(final_index+1,i) 
          break
        end
        final_index+=1   
      end
    end
  final
end

array = [6, 5, 3, 1, 8, 7, 2, 4]
p insertion_sort(array)