allow explicit args=None in use_effect

Author: rmorshea

flake8_idom_hooks/exhaustive_deps.py

@@ -140,13 +140,15 @@ def _get_dependency_names_from_expression(
                         ),
                     )
             return dep_names
-        else:
+        elif not (
+            isinstance(dependency_expr, ast.Constant) and dependency_expr.value is None
+        ):
             self._save_error(
                 202,
                 dependency_expr,
                 (
-                    f"dependency args of {hook_name!r} should be a literal list or "
-                    f"tuple - not expression type {type(dependency_expr).__name__!r}"
+                    f"dependency args of {hook_name!r} should be a literal list, tuple, "
+                    f"or None - not expression type {type(dependency_expr).__name__!r}"
                 ),
             )
             return None

tests/hook_usage_test_cases.py

@@ -200,10 +200,15 @@ def impropper_usage_of_effect_as_decorator():
 
     use_effect(
         lambda: None,
-        # error: ROH202 dependency args of 'use_effect' should be a literal list or tuple - not expression type 'Name'
+        # error: ROH202 dependency args of 'use_effect' should be a literal list, tuple, or None - not expression type 'Name'
         not_a_list_or_tuple,
     )
 
+    use_effect(
+        lambda: None,
+        args=None,  # Ok, to explicitely set None
+    )
+
 
 def make_component():
     # nested component definitions are ok.