Solution for array rotate problem.

A small array rotate solution with passing tests.
Solution uses only Array#unshift and Array#pop.

Author: keppy

array_rotate/solutions/keppy.rb

@@ -0,0 +1,11 @@
+class StringAutoma
+
+  def self.solve(set, n)
+    # set is an array, n is an integer.
+    n.times do
+      set.unshift(set.pop())
+    end
+    return set
+  end
+
+end

array_rotate/solutions/keppy_test.rb

@@ -0,0 +1,26 @@
+require 'minitest/autorun'
+
+require_relative './keppy.rb'
+
+class StringAutomaTest < MiniTest::Unit::TestCase
+  def test_one_step
+    set = [1, 2, 3, 4, 5, 6]
+    expected = [6, 1, 2, 3, 4, 5]
+    n = 1
+    assert_equal(expected, StringAutoma.solve(set,n))
+  end
+
+  def test_odd_split
+    set = [1, 2, 3, 4, 5, 6, 1, 2, 3]
+    expected = [1, 2, 3, 1, 2, 3, 4, 5, 6]
+    n = 3
+    assert_equal(expected, StringAutoma.solve(set,n))
+  end
+
+  def test_over_step
+    set = [1, 2, 3]
+    expected = [3, 1, 2]
+    n = 4
+    assert_equal(expected, StringAutoma.solve(set,n))
+  end
+end