core: migrate code to benefit from 3.9 stuff (#401)

for now keeping ruff on 3.8 target version, need to sort out modules as well

my/core/tests/auto_stats.py

@@ -2,11 +2,11 @@
 Helper 'module' for test_guess_stats
 """
 
+from collections.abc import Iterable, Iterator, Sequence
 from contextlib import contextmanager
 from dataclasses import dataclass
 from datetime import datetime, timedelta
 from pathlib import Path
-from typing import Iterable, Iterator, Sequence
 
 
 @dataclass

my/core/tests/common.py

@@ -1,6 +1,8 @@
+from __future__ import annotations
+
 import os
+from collections.abc import Iterator
 from contextlib import contextmanager
-from typing import Iterator, Optional
 
 import pytest
 
@@ -15,7 +17,7 @@ skip_if_uses_optional_deps = pytest.mark.skipif(
 
 # TODO maybe move to hpi core?
 @contextmanager
-def tmp_environ_set(key: str, value: Optional[str]) -> Iterator[None]:
+def tmp_environ_set(key: str, value: str | None) -> Iterator[None]:
     prev_value = os.environ.get(key)
     if value is None:
         os.environ.pop(key, None)

my/core/tests/denylist.py

@@ -1,8 +1,9 @@
 import json
 import warnings
+from collections.abc import Iterator
 from datetime import datetime
 from pathlib import Path
-from typing import Iterator, NamedTuple
+from typing import NamedTuple
 
 from ..denylist import DenyList
 

my/core/tests/test_cachew.py

@@ -1,6 +1,6 @@
-from .common import skip_if_uses_optional_deps as pytestmark
+from __future__ import annotations
 
-from typing import List
+from .common import skip_if_uses_optional_deps as pytestmark
 
 # TODO ugh, this is very messy.. need to sort out config overriding here
 
@@ -16,7 +16,7 @@ def test_cachew() -> None:
 
     # TODO ugh. need doublewrap or something to avoid having to pass parens
     @mcachew()
-    def cf() -> List[int]:
+    def cf() -> list[int]:
         nonlocal called
         called += 1
         return [1, 2, 3]
@@ -43,7 +43,7 @@ def test_cachew_dir_none() -> None:
         called = 0
 
         @mcachew(cache_path=cache_dir() / 'ctest')
-        def cf() -> List[int]:
+        def cf() -> list[int]:
             nonlocal called
             called += 1
             return [called, called, called]

my/core/tests/test_config.py

@@ -2,8 +2,8 @@
 Various tests that are checking behaviour of user config wrt to various things
 """
 
-import sys
 import os
+import sys
 from pathlib import Path
 
 import pytest