cast curl debug messages to str

since they come in as bytes on Python 3

diff --git a/tornado/curl_httpclient.py b/tornado/curl_httpclient.py
index eef4a17a6b4a7e6e30c2db0ab5b1f44c2791ebea..8558d65c953813ea292f0e9ba6ca593d9c7f6665 100644 (file)
--- a/tornado/curl_httpclient.py
+++ b/tornado/curl_httpclient.py
@@ -493,6 +493,7 @@ class CurlAsyncHTTPClient(AsyncHTTPClient):
 
     def _curl_debug(self, debug_type, debug_msg):
         debug_types = ('I', '<', '>', '<', '>')
+        debug_msg = native_str(debug_msg)
         if debug_type == 0:
             curl_log.debug('%s', debug_msg.strip())
         elif debug_type in (1, 2):