Fix broken config UTs

https://github.com/matrix-org/synapse/pull/2755 broke log-config generation,
which in turn broke the unit tests.

1 files changed, 2 insertions, 2 deletions

diff --git a/synapse/config/logger.py b/synapse/config/logger.py

index 9e8003ad65..0922125187 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -74,7 +74,6 @@ class LoggingConfig(Config):
         self.log_file = self.abspath(config.get("log_file"))
 
     def default_config(self, config_dir_path, server_name, **kwargs):
-        log_file = self.abspath("homeserver.log")
         log_config = self.abspath(
             os.path.join(config_dir_path, server_name + ".log.config")
         )
@@ -117,9 +116,10 @@ class LoggingConfig(Config):
     def generate_files(self, config):
         log_config = config.get("log_config")
         if log_config and not os.path.exists(log_config):
+            log_file = self.abspath("homeserver.log")
             with open(log_config, "wb") as log_config_file:
                 log_config_file.write(
-                    DEFAULT_LOG_CONFIG.substitute(log_file=config["log_file"])
+                    DEFAULT_LOG_CONFIG.substitute(log_file=log_file)
                 )