Avoid erroring with empty vars files

src/ansiblelint/rules/var_naming.py

@@ -105,6 +105,8 @@ def matchplay(self, file: Lintable, data: odict[str, Any]) -> List[MatchError]:
         results: List[MatchError] = []
         raw_results: List[MatchError] = []
 
+        if not data:
+            return results
         # If the Play uses the 'vars' section to set variables
         our_vars = data.get("vars", {})
         for key in our_vars.keys():
@@ -161,7 +163,7 @@ def matchyaml(self, file: Lintable) -> List[MatchError]:
         raw_results: List[MatchError] = []
         meta_data: Dict[AnsibleUnicode, Any] = {}
 
-        if str(file.kind) == "vars":
+        if str(file.kind) == "vars" and file.data:
             meta_data = parse_yaml_from_file(str(file.path))
             for key in meta_data.keys():
                 if self.is_invalid_variable_name(key):

src/ansiblelint/yaml_utils.py

@@ -204,6 +204,10 @@ def nested_items_path(
 
     :returns: each iteration yields the key (of the parent dict) or the index (lists)
     """
+    # As typing and mypy cannot effectively ensure we are called only with
+    # valid data, we better ignore: NoneType, [], {}, str
+    if not data_collection or isinstance(data_collection, str):
+        return
     yield from _nested_items_path(data_collection=data_collection, parent_path=[])