anchor.diff:      usage(parser);
     }
   
  -  var client = http.Client();
  +  final client = http.Client();
   
  -  var lines = await File(options['result_file']).readAsLines();
  -  var token = await File(options['auth_token']).readAsString();
  +  final lines = await File(options['result_file']).readAsLines();
  +  final token = await File(options['auth_token']).readAsString();
     // Construct pubsub messages.
     var line = 0;
  +  var numMessages = 0;
     while (line < lines.length) {
  -    var message = StringBuffer();
  +    final message = StringBuffer();
       message.write('[');
       message.write(lines[line++]);
       var messageLines = 1;
  
positive.code:     print('Status ${response.statusCode}');
      print('Response: ${response.body}');
    }
    client.close();
  }
  
negative.code:       messageLines++;
      }
      message.write(']');
      numMessages++;
      final attributes = {
        if (line == lines.length) 'num_messages': numMessages.toString()
      };
      var base64data = base64Encode(utf8.encode(message.toString()));
      var messageObject = {
        'messages': [
          {'attributes': attributes, 'data': base64data}
        ]
      };
      var jsonMessage = jsonEncode(messageObject);
      var headers = {'Authorization': 'Bearer $token'};
      var response =
          await client.post(postUrl, headers: headers, body: jsonMessage);
  