Avoid erroring with empty vars files (#2310)

- Empty YAML files should not longer produce errors
- We now made the broad rule exception catching to warning instead of
  debug, so we make it less likely to miss these, especially as they
  are almost always sing of a corner-case that we did not cover.

.github/workflows/tox.yml

@@ -165,7 +165,7 @@ jobs:
       WSLENV: FORCE_COLOR:PYTEST_REQPASS:TOXENV:TOX_PARALLEL_NO_SPINNER
       # Number of expected test passes, safety measure for accidental skip of
       # tests. Update value if you add/remove tests.
-      PYTEST_REQPASS: 661
+      PYTEST_REQPASS: 660
 
     steps:
       - name: Activate WSL1

src/ansiblelint/_internal/rules.py

@@ -61,7 +61,7 @@ def getmatches(self, file: Lintable) -> List[MatchError]:
                 try:
                     matches.extend(method(file))
                 except Exception as exc:  # pylint: disable=broad-except
-                    _logger.debug(
+                    _logger.warning(
                         "Ignored exception from %s.%s: %s",
                         self.__class__.__name__,
                         method,

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
+    if data_collection is None:
+        return
     yield from _nested_items_path(data_collection=data_collection, parent_path=[])
 
 

test/test_yaml_utils.py

@@ -64,9 +64,9 @@ def test_nested_items_path() -> None:
         "string",
         42,
         1.234,
-        None,
         ("tuple",),
         {"set"},
+        # NoneType is no longer include, as we assume we have to ignore it
     ),
 )
 def test_nested_items_path_raises_typeerror(invalid_data_input: Any) -> None: