Python 3.10 cleanup.

Author: coady

CHANGELOG.md

@@ -7,6 +7,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 ### Changed
 * Python >=3.10 required
 
+### Fixed
+* `multidispatch` allows pending references
+
 ## [2.0](https://pypi.org/project/multimethod/2.0/) - 2024-12-26
 ### Removed
 * Resolving ambiguity using positional distance

multimethod/__init__.py

@@ -7,11 +7,10 @@
 import types
 import typing
 from collections.abc import Callable, Iterable, Iterator, Mapping
-from typing import Any, Literal, TypeVar, Union, get_type_hints, overload
+from typing import Any, Literal, NewType, TypeVar, Union, get_type_hints, overload
 
 
-class DispatchError(TypeError):
-    pass
+class DispatchError(TypeError): ...
 
 
 def get_origin(tp):
@@ -48,7 +47,7 @@ class subtype(abc.ABCMeta):
     def __new__(cls, tp, *args):
         if tp is Any:
             return object
-        if hasattr(tp, '__supertype__'):  # isinstance(..., NewType) only supported >=3.10
+        if isinstance(tp, NewType):
             return cls(tp.__supertype__, *args)
         if hasattr(typing, 'TypeAliasType') and isinstance(tp, typing.TypeAliasType):
             return cls(tp.__value__, *args)
@@ -414,8 +413,7 @@ class multimeta(type):
     """Convert all callables in namespace to multimethods."""
 
     class __prepare__(dict):
-        def __init__(*args):
-            pass
+        def __init__(*args): ...
 
         def __setitem__(self, key, value):
             if callable(value):

tests/test_subscripts.py

@@ -31,7 +31,6 @@ def func(arg: Literal['a', 0]):
         func(0.0)
 
 
-@pytest.mark.skipif(sys.version_info < (3, 10), reason="Union syntax added in 3.10")
 def test_union():
     assert issubclass(int, subtype(int | float))
     assert issubclass(subtype(int | float), subtype(int | float | None))