style: Integrate no-optional pre-commit hook (#133)

[no-optional](https://github.com/Kludex/no-optional) pre-commit hook
allows to ensure that all `Optional[T]` type annotations will be
replaced to `Union[T, None]` as they are similar to `T | None` from
Python 3.10.

.pre-commit-config.yaml

@@ -84,11 +84,16 @@ repos:
   - repo: "https://github.com/asottile/yesqa"
     rev: "v1.4.0"
     hooks:
-      - id: yesqa
+      - id: "yesqa"
         name: "Lint code (yesqa)"
         additional_dependencies: *flake8_additional_dependencies
         exclude: ^docs/.*$
 
+  - repo: "https://github.com/Kludex/no-optional"
+    rev: "0.4.0"
+    hooks:
+      - id: "no_optional"
+
   - repo: "local"
     hooks:
       - id: "mypy"

pyproject.toml

@@ -120,7 +120,7 @@ pytest-aiohttp = "^1.0.4"
 pytest-cov = "^3.0.0"
 
 [tool.pytest.ini_options]
-minversion = "7.1.2"
+minversion = "7.1.3"
 addopts = "--cov --no-cov-on-fail"
 testpaths = ["./tests/"]
 log_level = "info"

src/aiohttp_middlewares/error.py

@@ -85,7 +85,7 @@ async def api_error(request: web.Request) -> web.Response:
 import logging
 from contextlib import contextmanager
 from functools import partial
-from typing import Dict, Iterator, Optional, Tuple, Union
+from typing import Dict, Iterator, Tuple, Union
 
 import attr
 from aiohttp import web
@@ -223,8 +223,8 @@ def get_error_from_request(request: web.Request) -> Exception:
 
 
 def get_error_handler(
-    request: web.Request, config: Optional[Config]
-) -> Optional[Handler]:
+    request: web.Request, config: Union[Config, None]
+) -> Union[Handler, None]:
     """Find error handler matching current request path if any."""
     if not config:
         return None