chore: replace TypeVar with native syntax

unwind/db.py

@@ -1,7 +1,7 @@
 import contextlib
 import logging
 from pathlib import Path
-from typing import Any, AsyncGenerator, Iterable, Literal, Sequence, Type, TypeVar
+from typing import Any, AsyncGenerator, Iterable, Literal, Sequence, Type
 
 import sqlalchemy as sa
 from sqlalchemy.ext.asyncio import AsyncConnection, AsyncEngine, create_async_engine
@@ -29,7 +29,6 @@ from .models import (
 from .types import ULID
 
 log = logging.getLogger(__name__)
-T = TypeVar("T")
 
 _engine: AsyncEngine | None = None
 
@@ -240,7 +239,7 @@ async def add(conn: Connection, /, item: Model) -> None:
     # Support late initializing - used for optimization.
     if getattr(item, "_is_lazy", False):
         assert hasattr(item, "_lazy_init")
-        item._lazy_init()  # pyright: ignore [reportGeneralTypeIssues]
+        item._lazy_init()  # pyright: ignore[reportAttributeAccessIssue]
 
     table: sa.Table = item.__table__
     values = asplain(item, serialize=True)
@@ -262,17 +261,14 @@ async def fetch_one(
     return result.first()
 
 
-ModelType = TypeVar("ModelType", bound=Model)
-
-
-async def get(
+async def get[T: Model](
     conn: Connection,
     /,
-    model: Type[ModelType],
+    model: Type[T],
     *,
     order_by: tuple[sa.Column, Literal["asc", "desc"]] | None = None,
     **field_values,
-) -> ModelType | None:
+) -> T | None:
     """Load a model instance from the database.
 
     Passing `field_values` allows to filter the item to load. You have to encode the
@@ -295,9 +291,9 @@ async def get(
     return fromplain(model, row._mapping, serialized=True) if row else None
 
 
-async def get_many(
-    conn: Connection, /, model: Type[ModelType], **field_sets: set | list
-) -> Iterable[ModelType]:
+async def get_many[T: Model](
+    conn: Connection, /, model: Type[T], **field_sets: set | list
+) -> Iterable[T]:
     """Return the items with any values matching all given field sets.
 
     This is similar to `get_all`, but instead of a scalar value a list of values
@@ -314,9 +310,9 @@ async def get_many(
     return (fromplain(model, row._mapping, serialized=True) for row in rows)
 
 
-async def get_all(
-    conn: Connection, /, model: Type[ModelType], **field_values
-) -> Iterable[ModelType]:
+async def get_all[T: Model](
+    conn: Connection, /, model: Type[T], **field_values
+) -> Iterable[T]:
     """Filter all items by comparing all given field values.
 
     If no filters are given, all items will be returned.
@@ -333,7 +329,7 @@ async def update(conn: Connection, /, item: Model) -> None:
     # Support late initializing - used for optimization.
     if getattr(item, "_is_lazy", False):
         assert hasattr(item, "_lazy_init")
-        item._lazy_init()  # pyright: ignore [reportGeneralTypeIssues]
+        item._lazy_init()  # pyright: ignore[reportAttributeAccessIssue]
 
     table: sa.Table = item.__table__
     values = asplain(item, serialize=True)

unwind/imdb_import.py

@@ -5,7 +5,7 @@ import logging
 from dataclasses import dataclass, fields
 from datetime import datetime, timezone
 from pathlib import Path
-from typing import Generator, Literal, Type, TypeVar, overload
+from typing import Generator, Literal, Type, overload
 
 from . import config, db, request
 from .db import add_or_update_many_movies
@@ -14,8 +14,6 @@ from .models import Movie
 
 log = logging.getLogger(__name__)
 
-T = TypeVar("T")
-
 # See
 # - https://developer.imdb.com/non-commercial-datasets/
 # - https://datasets.imdbws.com/
@@ -127,7 +125,7 @@ def read_imdb_tsv(
 
 
 @overload
-def read_imdb_tsv(
+def read_imdb_tsv[T](
     path: Path, row_type: Type[T], *, unpack: Literal[True] = True
 ) -> Generator[T, None, None]: ...
 

unwind/models.py

@@ -12,10 +12,8 @@ from typing import (
     Mapping,
     Protocol,
     Type,
-    TypeAlias,
     TypeAliasType,
     TypedDict,
-    TypeVar,
     Union,
     get_args,
     get_origin,
@@ -27,12 +25,10 @@ from sqlalchemy.orm import registry
 from .types import ULID
 from .utils import json_dump
 
-JSONScalar: TypeAlias = int | float | str | None
+type JSONScalar = int | float | str | None
 type JSON = JSONScalar | list["JSON"] | dict[str, "JSON"]
 type JSONObject = dict[str, JSON]
 
-T = TypeVar("T")
-
 
 class Model(Protocol):
     __table__: ClassVar[Table]
@@ -53,6 +49,10 @@ metadata.naming_convention = {
 
 
 def annotations(tp: Type) -> tuple | None:
+    # Support type aliases and generic aliases.
+    if isinstance(tp, TypeAliasType) or hasattr(tp, "__value__"):
+        tp = tp.__value__
+
     return tp.__metadata__ if hasattr(tp, "__metadata__") else None  # type: ignore
 
 
@@ -110,7 +110,7 @@ def optional_fields(o):
             yield f
 
 
-def _id(x: T) -> T:
+def _id[T](x: T) -> T:
     """Return the given argument, aka. the identity function."""
     return x
 
@@ -168,7 +168,7 @@ def asplain(
             ), f"Type mismatch: {f.name!a} ({target!a} != {type(v)!a})"
             d[f.name] = v
         elif target in {Literal}:
-            assert isinstance(v, JSONScalar)
+            assert isinstance(v, JSONScalar.__value__)
             d[f.name] = v
         else:
             raise ValueError(f"Unsupported value type: {f.name!a}: {type(v)!a}")
@@ -176,7 +176,7 @@ def asplain(
     return d
 
 
-def fromplain(cls: Type[T], d: Mapping, *, serialized: bool = False) -> T:
+def fromplain[T](cls: Type[T], d: Mapping, *, serialized: bool = False) -> T:
     """Return an instance of the given model using the given data.
 
     If `serialized` is `True`, collection types (lists, dicts, etc.) will be
@@ -379,7 +379,7 @@ dataclass containing the ID of the linked data.
 The contents of the Relation are ignored or discarded when using
 `asplain`, `fromplain`, and `validate`.
 """
-Relation: TypeAlias = Annotated[T | None, _RelationSentinel]
+type Relation[T] = Annotated[T | None, _RelationSentinel]
 
 
 type Access = Literal[

unwind/request.py

@@ -11,7 +11,7 @@ from hashlib import md5
 from pathlib import Path
 from random import random
 from time import sleep, time
-from typing import Any, Callable, ParamSpec, TypeVar, cast, overload
+from typing import Any, Callable, cast, overload
 
 import bs4
 import httpx
@@ -24,13 +24,10 @@ if config.debug and config.cachedir:
     config.cachedir.mkdir(exist_ok=True)
 
 
-_shared_asession = None
-
 _ASession_T = httpx.AsyncClient
-_Response_T = httpx.Response
+type _Response_T = httpx.Response
 
-_T = TypeVar("_T")
-_P = ParamSpec("_P")
+_shared_asession: _ASession_T | None = None
 
 
 @asynccontextmanager
@@ -59,17 +56,17 @@ async def asession():
         _shared_asession = None
 
 
-def _throttle(
+def _throttle[T, **P](
     times: int, per_seconds: float, jitter: Callable[[], float] | None = None
-) -> Callable[[Callable[_P, _T]], Callable[_P, _T]]:
+) -> Callable[[Callable[P, T]], Callable[P, T]]:
     calls: deque[float] = deque(maxlen=times)
 
     if jitter is None:
         jitter = lambda: 0.0  # noqa: E731
 
-    def decorator(func: Callable[_P, _T]) -> Callable[_P, _T]:
+    def decorator(func: Callable[P, T]) -> Callable[P, T]:
         @wraps(func)
-        def inner(*args: _P.args, **kwds: _P.kwargs):
+        def inner(*args: P.args, **kwds: P.kwargs):
             # clean up
             while calls:
                 if calls[0] + per_seconds > time():