Add return type annotations to functions that always return None

I don't see a way to make mypy require return type annotations only when
there are non-bare return statements in the function.

rock_paper_sand/config_subcommand.py

@@ -27,7 +27,7 @@
 class Lint(subcommand.Subcommand):
     """Lints the config file."""
 
-    def run(self, args: argparse.Namespace):
+    def run(self, args: argparse.Namespace) -> None:
         """See base class."""
         del args  # Unused.
         with network.null_requests_session() as session:
@@ -49,7 +49,7 @@ def run(self, args: argparse.Namespace):
 class Main(subcommand.ContainerSubcommand):
     """Main config command."""
 
-    def __init__(self, parser: argparse.ArgumentParser):
+    def __init__(self, parser: argparse.ArgumentParser) -> None:
         """See base class."""
         super().__init__(parser)
         subparsers = parser.add_subparsers()

rock_paper_sand/config_test.py

@@ -124,7 +124,7 @@ def test_lint(
         *,
         config_data: Any,
         expected_results: Any,
-    ):
+    ) -> None:
         self.enter_context(
             flagsaver.flagsaver(
                 (
@@ -143,7 +143,7 @@ def test_lint(
 
         self.assertEqual(expected_results, results)
 
-    def test_example_config(self):
+    def test_example_config(self) -> None:
         with flagsaver.flagsaver(
             (
                 flags_and_constants.CONFIG_FILE,

rock_paper_sand/flags_and_constants_test.py

@@ -40,15 +40,15 @@ def test_get_app_dir(
         self,
         env: Mapping[str, str],
         expected_path: pathlib.Path,
-    ):
+    ) -> None:
         with mock.patch.dict(os.environ, env, clear=True):
             actual_path = flags_and_constants._get_app_dir(
                 xdg_variable_name="XDG_FOO_HOME",
                 relative_fallback_path=pathlib.Path("foo"),
             )
         self.assertEqual(expected_path, actual_path)
 
-    def test_get_app_dir_error(self):
+    def test_get_app_dir_error(self) -> None:
         with self.assertRaisesRegex(ValueError, "No HOME directory"):
             with mock.patch.dict(os.environ, {}, clear=True):
                 flags_and_constants._get_app_dir(

rock_paper_sand/justwatch.py

@@ -70,7 +70,7 @@ def __init__(
         *,
         session: requests.Session,
         base_url: str = _BASE_URL,
-    ):
+    ) -> None:
         self._session = session
         self._base_url = base_url
         self._cache = {}
@@ -157,7 +157,7 @@ class _Availability:
         default_factory=collections.Counter
     )
 
-    def update(self, other: "_Availability"):
+    def update(self, other: "_Availability") -> None:
         self.total_episode_count += other.total_episode_count
         self.episode_count_by_offer.update(other.episode_count_by_offer)
 
@@ -198,7 +198,7 @@ def __init__(
         filter_config: config_pb2.JustWatchFilter,
         *,
         api: Api,
-    ):
+    ) -> None:
         self._config = filter_config
         self._api = api
 

rock_paper_sand/justwatch_subcommand.py

@@ -25,14 +25,14 @@
 from rock_paper_sand import subcommand
 
 
-def _add_locale_arg(parser: argparse.ArgumentParser):
+def _add_locale_arg(parser: argparse.ArgumentParser) -> None:
     parser.add_argument("--locale", help="JustWatch locale.", required=True)
 
 
 class Locales(subcommand.Subcommand):
     """Prints the available JustWatch locales."""
 
-    def run(self, args: argparse.Namespace):
+    def run(self, args: argparse.Namespace) -> None:
         """See base class."""
         del args  # Unused.
         with network.requests_session() as session:
@@ -43,12 +43,12 @@ def run(self, args: argparse.Namespace):
 class MonetizationTypes(subcommand.Subcommand):
     """Prints the available JustWatch monetization types."""
 
-    def __init__(self, parser: argparse.ArgumentParser):
+    def __init__(self, parser: argparse.ArgumentParser) -> None:
         """See base class."""
         super().__init__(parser)
         _add_locale_arg(parser)
 
-    def run(self, args: argparse.Namespace):
+    def run(self, args: argparse.Namespace) -> None:
         """See base class."""
         with network.requests_session() as session:
             api = justwatch.Api(session=session)
@@ -63,12 +63,12 @@ def run(self, args: argparse.Namespace):
 class Providers(subcommand.Subcommand):
     """Prints the available JustWatch providers."""
 
-    def __init__(self, parser: argparse.ArgumentParser):
+    def __init__(self, parser: argparse.ArgumentParser) -> None:
         """See base class."""
         super().__init__(parser)
         _add_locale_arg(parser)
 
-    def run(self, args: argparse.Namespace):
+    def run(self, args: argparse.Namespace) -> None:
         """See base class."""
         with network.requests_session() as session:
             api = justwatch.Api(session=session)
@@ -78,7 +78,7 @@ def run(self, args: argparse.Namespace):
 class Search(subcommand.Subcommand):
     """Searches for a media item."""
 
-    def __init__(self, parser: argparse.ArgumentParser):
+    def __init__(self, parser: argparse.ArgumentParser) -> None:
         """See base class."""
         super().__init__(parser)
         _add_locale_arg(parser)
@@ -90,7 +90,7 @@ def run(
         *,
         out_file: IO[str] = sys.stdout,
         api: justwatch.Api | None = None,
-    ):
+    ) -> None:
         """See base class."""
         with network.requests_session() as session:
             if api is None:
@@ -117,7 +117,7 @@ def run(
 class Main(subcommand.ContainerSubcommand):
     """Main JustWatch API command."""
 
-    def __init__(self, parser: argparse.ArgumentParser):
+    def __init__(self, parser: argparse.ArgumentParser) -> None:
         """See base class."""
         super().__init__(parser)
         subparsers = parser.add_subparsers()

rock_paper_sand/justwatch_subcommand_test.py

@@ -25,13 +25,13 @@
 
 
 class JustWatchSubcommandTest(parameterized.TestCase):
-    def setUp(self):
+    def setUp(self) -> None:
         super().setUp()
         self._mock_api = mock.create_autospec(
             justwatch.Api, instance=True, spec_set=True
         )
 
-    def test_search(self):
+    def test_search(self) -> None:
         parser = argparse.ArgumentParser()
         output = io.StringIO()
         self._mock_api.post.return_value = {

rock_paper_sand/justwatch_test.py

@@ -49,7 +49,7 @@ def _offer(
 
 
 class JustWatchApiTest(parameterized.TestCase):
-    def setUp(self):
+    def setUp(self) -> None:
         super().setUp()
         self._mock_session = mock.create_autospec(
             requests.Session, spec_set=True, instance=True
@@ -60,7 +60,7 @@ def setUp(self):
         )
         self._mock_session.reset_mock()
 
-    def test_get(self):
+    def test_get(self) -> None:
         self._mock_session.get.return_value.json.return_value = "foo"
 
         data = self._api.get("bar")
@@ -75,7 +75,7 @@ def test_get(self):
             self._mock_session.mock_calls,
         )
 
-    def test_cache(self):
+    def test_cache(self) -> None:
         self._mock_session.get.return_value.json.return_value = "foo"
         self._api.get("bar")
         self._mock_session.reset_mock()
@@ -85,7 +85,7 @@ def test_cache(self):
         self.assertEqual("foo", data)
         self.assertEmpty(self._mock_session.mock_calls)
 
-    def test_post(self):
+    def test_post(self) -> None:
         self._mock_session.post.return_value.json.return_value = "foo"
 
         data = self._api.post("bar", ["payload"])
@@ -100,7 +100,7 @@ def test_post(self):
             self._mock_session.mock_calls,
         )
 
-    def test_locales(self):
+    def test_locales(self) -> None:
         self._mock_session.get.return_value.json.return_value = [
             {"full_locale": "foo"},
             {"full_locale": "bar"},
@@ -113,7 +113,7 @@ def test_locales(self):
             f"{self._base_url}/locales/state"
         )
 
-    def test_providers(self):
+    def test_providers(self) -> None:
         self._mock_session.get.return_value.json.return_value = [
             {"short_name": "foo", "clear_name": "Foo+"},
         ]
@@ -125,7 +125,7 @@ def test_providers(self):
             f"{self._base_url}/providers/locale/en_US"
         )
 
-    def test_providers_cached(self):
+    def test_providers_cached(self) -> None:
         self._mock_session.get.return_value.json.return_value = [
             {"short_name": "foo", "clear_name": "Foo+"},
         ]
@@ -137,7 +137,7 @@ def test_providers_cached(self):
         self.assertEqual({"foo": "Foo+"}, providers)
         self.assertEmpty(self._mock_session.mock_calls)
 
-    def test_provider_name(self):
+    def test_provider_name(self) -> None:
         self._mock_session.get.return_value.json.return_value = [
             {"short_name": "foo", "clear_name": "Foo+"},
         ]
@@ -146,11 +146,11 @@ def test_provider_name(self):
 
         self.assertEqual("Foo+", provider_name)
 
-    def test_provider_name_not_found(self):
+    def test_provider_name_not_found(self) -> None:
         self._mock_session.get.return_value.json.return_value = []
         self.assertEqual("foo", self._api.provider_name("foo", locale="en_US"))
 
-    def test_monetization_types(self):
+    def test_monetization_types(self) -> None:
         self._mock_session.get.return_value.json.return_value = [
             {"monetization_types": ["foo"]},
             {"monetization_types": ["bar", "quux"]},
@@ -166,7 +166,7 @@ def test_monetization_types(self):
 
 
 class FilterTest(parameterized.TestCase):
-    def setUp(self):
+    def setUp(self) -> None:
         self._mock_api = mock.create_autospec(
             justwatch.Api, spec_set=True, instance=True
         )
@@ -446,7 +446,7 @@ def test_filter(
         media_item: Any,
         api_data: Mapping[str, Any] = immutabledict.immutabledict(),
         expected_result: media_filter.FilterResult,
-    ):
+    ) -> None:
         self._mock_api.get.side_effect = lambda relative_url: api_data[
             relative_url
         ]
@@ -461,7 +461,7 @@ def test_filter(
 
         self.assertEqual(expected_result, result)
 
-    def test_possible_unknown_placeholder_datetime(self):
+    def test_possible_unknown_placeholder_datetime(self) -> None:
         self._mock_api.get.return_value = {
             "offers": [
                 _offer(

rock_paper_sand/main.py

@@ -28,7 +28,7 @@
 
 
 class MainCommand(subcommand.ContainerSubcommand):
-    def __init__(self, parser: argparse.ArgumentParser):
+    def __init__(self, parser: argparse.ArgumentParser) -> None:
         """See base class."""
         super().__init__(parser)
         subparsers = parser.add_subparsers()
@@ -52,7 +52,7 @@ def __init__(self, parser: argparse.ArgumentParser):
         )
 
 
-def main():
+def main() -> None:
     parser = argparse_flags.ArgumentParser()
     main_command = MainCommand(parser)
     args = parser.parse_args()

rock_paper_sand/media_filter.py

@@ -51,7 +51,7 @@ def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
 class Not(Filter):
     """Inverts another filter."""
 
-    def __init__(self, child: Filter, /):
+    def __init__(self, child: Filter, /) -> None:
         self._child = child
 
     def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
@@ -63,7 +63,9 @@ def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
 class BinaryLogic(Filter):
     """Binary logic filter, i.e., "and" and "or"."""
 
-    def __init__(self, *children: Filter, op: Callable[[Iterable[bool]], bool]):
+    def __init__(
+        self, *children: Filter, op: Callable[[Iterable[bool]], bool]
+    ) -> None:
         self._children = children
         self._op = op
 
@@ -83,7 +85,7 @@ def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
 class HasParts(Filter):
     """Matches based on whether there are any child parts."""
 
-    def __init__(self, has_parts: bool):
+    def __init__(self, has_parts: bool) -> None:
         self._has_parts = has_parts
 
     def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
@@ -94,7 +96,7 @@ def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
 class Done(Filter):
     """Matches based on the `done` field."""
 
-    def __init__(self, done: str):
+    def __init__(self, done: str) -> None:
         self._done = multi_level_set.parse_number(done)
 
     def filter(self, media_item: config_pb2.MediaItem) -> FilterResult:
@@ -112,7 +114,7 @@ def __init__(
         self,
         field_getter: Callable[[config_pb2.MediaItem], str],
         matcher_config: config_pb2.StringFieldMatcher,
-    ):
+    ) -> None:
         self._field_getter = field_getter
         match matcher_config.WhichOneof("method"):
             case "empty":
@@ -143,7 +145,7 @@ def __init__(
         justwatch_factory: (
             Callable[[config_pb2.JustWatchFilter], Filter] | None
         ) = None,
-    ):
+    ) -> None:
         """Initializer.
 
         Args:
@@ -153,7 +155,7 @@ def __init__(
         self._justwatch_factory = justwatch_factory
         self._filter_by_name = {}
 
-    def register(self, name: str, filter_: Filter):
+    def register(self, name: str, filter_: Filter) -> None:
         """Registers a named filter."""
         if name in self._filter_by_name:
             raise ValueError(f"Filter {name!r} is defined multiple times.")