A Ruby implementation of a Quicksort Algorithm

quick_sort.rb

require 'test/unit'

module Sort 
    extend self

    def quicksort(container)
        return container if container.size < 2
        
        pivot = container.size / 2
        e     = container[pivot]
        container.delete_at pivot

        lesser  = []
        greater = []

        container.each { |item| item < e ? lesser << item : greater << item }

        quicksort(lesser) + [e] + quicksort(greater) 
    end
end

if __FILE__ == $0
    class TestQuicksort < Test::Unit::TestCase
        def setup
            @unsorted = [3, 5, 2, 4, 6, 1]
            @sorted = [1, 2, 3, 4, 5, 6]
        end

        def test_mergesort
            assert_equal @sorted, Sort.quicksort(@unsorted)
        end
    end
end