Avoid trailing comma for single-argument with positional separator

[charliermarsh]

Summary

In #8921, we changed our parameter formatting behavior to add a trailing comma whenever a single-argument function breaks. This introduced a deviation in the case that a function contains a single argument, but also includes a positional-only or keyword-only separator.

Closes #9074.

[github-actions]

ruff-ecosystem results

Formatter (stable)

ℹ️ ecosystem check detected format changes. (+2 -3 lines in 1 file in 41 projects)

zulip/zulip (+2 -3 lines across 1 file)

zerver/lib/message.py~L1249

 
 
 def aggregate_pms(
-    *,
-    input_dict: Dict[int, RawUnreadDirectMessageDict],
+    *, input_dict: Dict[int, RawUnreadDirectMessageDict]
 ) -> List[UnreadDirectMessageInfo]:
     lookup_dict: Dict[int, UnreadDirectMessageInfo] = {}
     for message_id, attribute_dict in input_dict.items():

Formatter (preview)

ℹ️ ecosystem check detected format changes. (+2 -3 lines in 1 file in 41 projects)

zulip/zulip (+2 -3 lines across 1 file)

ruff format --preview

zerver/lib/message.py~L1249

 
 
 def aggregate_pms(
-    *,
-    input_dict: Dict[int, RawUnreadDirectMessageDict],
+    *, input_dict: Dict[int, RawUnreadDirectMessageDict]
 ) -> List[UnreadDirectMessageInfo]:
     lookup_dict: Dict[int, UnreadDirectMessageInfo] = {}
     for message_id, attribute_dict in input_dict.items():

[charliermarsh]

The one ecosystem change matches Black's formatting (i.e., it's more consistent than on main).

[BlindChickens]

Yes lets go.