unicode decode failures without an installed handler raise a LookupError

from wlav@4f03d87

Author: aaronj0

test/test_doc_features.py

@@ -1295,8 +1295,9 @@ def test_unicode(self):
             return to_str(chars);
         }}""")
 
-        with raises(UnicodeDecodeError):
+        with raises(Exception) as exc_info:
             CC.gbk_chinese().decode('utf-8')
+        assert isinstance(exc_info.value, (UnicodeDecodeError, LookupError))
 
         assert CC.gbk_chinese() == u'\u4e2d\u6587'.encode('gbk')
         if 0x3000000 <= sys.hexversion: