Add get next challenge

bit_manipulation/get_next/test_get_next_largest.py

@@ -0,0 +1,33 @@
+from nose.tools import assert_equal, assert_raises
+
+
+class TestBits(object):
+
+    def test_get_next_largest(self):
+        bits = Bits()
+        assert_raises(Exception, bits.get_next_largest, None)
+        assert_raises(Exception, bits.get_next_largest, 0)
+        assert_raises(Exception, bits.get_next_largest, -1)
+        num = int('011010111', base=2)
+        expected = int('011011011', base=2)
+        assert_equal(bits.get_next_largest(num), expected)
+        print('Success: test_get_next_largest')
+
+    def test_get_next_smallest(self):
+        bits = Bits()
+        assert_raises(Exception, bits.get_next_smallest, None)
+        assert_raises(Exception, bits.get_next_smallest, 0)
+        assert_raises(Exception, bits.get_next_smallest, -1)
+        num = int('011010111', base=2)
+        expected = int('011001111', base=2)
+        assert_equal(bits.get_next_smallest(num), expected)
+        print('Success: test_get_next_smallest')
+
+def main():
+    test = TestBits()
+    test.test_get_next_largest()
+    test.test_get_next_smallest()
+
+
+if __name__ == '__main__':
+    main()