Fix format_args when there are no positional arguments

When formatting arguments, don't output an extra leading comma if the
function has no positional arguments.

1 files changed, 3 insertions, 1 deletions

diff --git a/node_classes.py b/node_classes.py
index 92a152d..8c6ad8a 100644
--- a/node_classes.py
+++ b/node_classes.py
@@ -268,7 +268,9 @@ class Arguments(NodeNG, AssignTypeMixin):
 
     def format_args(self):
         """return arguments formatted as string"""
-        result = [_format_args(self.args, self.defaults)]
+        result = []
+        if self.args:
+            result.append(_format_args(self.args, self.defaults))
         if self.vararg:
             result.append('*%s' % self.vararg)
         if self.kwarg: