diff --git a/Tests/misc/py23_test.py b/Tests/misc/py23_test.py
index 6c5355239..c2be03691 100644
--- a/Tests/misc/py23_test.py
+++ b/Tests/misc/py23_test.py
@@ -389,5 +389,34 @@ class IsCloseTests(unittest.TestCase):
 		self.assertAllNotClose(fraction_examples, rel_tol=1e-9)
 
 
+@unittest.skipUnless(
+	(sys.version_info[0] == 2 and sys.maxunicode < 0x10FFFF),
+	"requires 'narrow' Python 2.7 build")
+class NarrowUnicodeBuildTest(unittest.TestCase):
+
+	def test_unichr(self):
+		from __builtin__ import unichr as narrow_unichr
+
+		self.assertRaises(
+			ValueError,
+			narrow_unichr, 0xFFFF + 1)
+
+		self.assertEqual(unichr(1114111), u'\U0010FFFF')
+
+		self.assertRaises(
+			ValueError,
+			unichr, 0x10FFFF + 1)
+
+	def test_byteord(self):
+		from __builtin__ import ord as narrow_ord
+
+		self.assertRaises(
+			TypeError,
+			narrow_ord, u'\U00010000')
+
+		self.assertEqual(byteord(u'\U00010000'), 0xFFFF + 1)
+		self.assertEqual(byteord(u'\U0010FFFF'), 1114111)
+
+
 if __name__ == "__main__":
 	sys.exit(unittest.main())