Auto merge of #513 - micbou:python-completer-log-level, r=Valloric

[READY] Pass ycmd logging level to JediHTTP

Now that [`JediHTTP` has an option to set its logging level](vheon/JediHTTP#15), we can pass `ycmd` logging level to it.

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ycmd/completers/python/jedi_completer.py

@@ -162,6 +162,7 @@ def _StartServer( self ):
         command = [ self._python_binary_path,
                     PATH_TO_JEDIHTTP,
                     '--port', str( self._jedihttp_port ),
+                    '--log', self._GetLoggingLevel(),
                     '--hmac-file-secret', hmac_file.name ]
 
       self._logfile_stdout = LOG_FILENAME_FORMAT.format(
@@ -180,6 +181,13 @@ def _GenerateHmacSecret( self ):
     return os.urandom( HMAC_SECRET_LENGTH )
 
 
+  def _GetLoggingLevel( self ):
+    # Tests are run with the NOTSET logging level but JediHTTP only accepts the
+    # predefined levels above (DEBUG, INFO, WARNING, etc.).
+    log_level = max( self._logger.getEffectiveLevel(), logging.DEBUG )
+    return logging.getLevelName( log_level ).lower()
+
+
   def _GetResponse( self, handler, request_data = {} ):
     """POST JSON data to JediHTTP server and return JSON response."""
     handler = ToBytes( handler )