--- a/Lib/test/test_peepholer.py	Thu Apr 14 07:51:57 2011 +0300
+++ b/Lib/test/test_peepholer.py	Thu Apr 14 15:51:14 2011 +0300
@@ -205,6 +205,24 @@
         asm = dis_single('a="x"*1000')
         self.assertIn('(1000)', asm)
 
+    def test_binary_subscr_on_unicode(self):
+        # valid code get optimized
+        asm = dis_single('"foo"[0]')
+        self.assertIn("('f')", asm)
+        self.assertNotIn('BINARY_SUBSCR', asm)
+        asm = dis_single('"\u0061\uffff"[1]')
+        self.assertIn("('\\uffff')", asm)
+        self.assertNotIn('BINARY_SUBSCR', asm)
+
+        # invalid code doesn't get optimized
+        # out of range
+        asm = dis_single('"fuu"[10]')
+        self.assertIn('BINARY_SUBSCR', asm)
+        # non-BMP char (see #5057)
+        asm = dis_single('"\U00012345"[0]')
+        self.assertIn('BINARY_SUBSCR', asm)
+
+
     def test_folding_of_unaryops_on_constants(self):
         for line, elem in (
             ('-0.5', '(-0.5)'),                     # unary negative