Allow date rotation to be disabled
diff --git a/src/lager_file_backend.erl b/src/lager_file_backend.erl
index 6e1d2ef..5fb24b9 100644
--- a/src/lager_file_backend.erl
+++ b/src/lager_file_backend.erl
@@ -296,7 +296,7 @@
validate_logfile_proplist(Tail, [{date, Spec}|Acc]);
{error, _} when Date == "" ->
%% legacy config allowed blanks
- validate_logfile_proplist(Tail, Acc);
+ validate_logfile_proplist(Tail, [{date, undefined}|Acc]);
{error, _} ->
throw({bad_config, "Invalid rotation date", Date})
end;