Remove 3.9 (#698)

Author: Tinche

.github/workflows/main.yml

@@ -16,7 +16,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14", "pypy3.10"]
+        python-version: ["3.10", "3.11", "3.12", "3.13", "3.14", "pypy3.10"]
       fail-fast: false
 
     steps:

.github/workflows/zizmor.yml

@@ -21,10 +21,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           persist-credentials: false
-      - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@v4
-        with:
-          version: "latest"
+      - uses: hynek/setup-cached-uv@757bedc3f972eb7227a1aa657651f15a8527c817  # v2.3.0
       - name: Run zizmor 🌈
         run: uvx zizmor --format sarif . > results.sarif
         env:

CONTRIBUTING.md

@@ -75,7 +75,7 @@ Now you can make your changes locally.
 ```shell
 $ just lint
 $ just test
-$ just --set python python3.9 test  # Test on other versions
+$ just --set python python3.10 test  # Test on other versions
 ```
 
 6. Write any necessary documentation, including updating the changelog (HISTORY.md). The docs can be built like so:

HISTORY.md

@@ -15,6 +15,8 @@ Our backwards-compatibility policy can be found [here](https://github.com/python
 
 - Fix structuring of nested generic classes with stringified annotations.
   ([#688](https://github.com/python-attrs/cattrs/pull/688))
+- Python 3.9 is no longer supported, as it is end-of-life. Use previous versions on this Python version.
+  ([#698](https://github.com/python-attrs/cattrs/pull/698))
 
 ## 25.3.0 (2025-10-07)
 

Justfile

@@ -6,19 +6,19 @@ sync version="":
     uv sync {{ if python != '' { '-p ' + python } else if version != '' { '-p ' + version } else  { '' } }} --all-groups --all-extras
 
 lint:
-	uv run -p python3.13 --group lint ruff check src/ tests bench
-	uv run -p python3.13 --group lint black --check src tests docs/conf.py
+	uv run -p python3.14 --group lint ruff check src/ tests bench
+	uv run -p python3.14 --group lint black --check src tests docs/conf.py
 
 test *args="-x --ff -n auto tests":
     uv run {{ if python != '' { '-p ' + python } else { '' } }} --all-extras --group test --group lint pytest {{args}}
 
 testall:
-    just python=python3.9 test
     just python=python3.10 test
     just python=pypy3.10 test
     just python=python3.11 test
     just python=python3.12 test
     just python=python3.13 test
+    just python=python3.14 test
 
 cov *args="-x --ff -n auto tests":
     uv run {{ if python != '' { '-p ' + python } else { '' } }} --all-extras --group test --group lint coverage run -m pytest {{args}}
@@ -27,12 +27,12 @@ cov *args="-x --ff -n auto tests":
     {{ if covcleanup == "true" { "@rm .coverage*" } else { "" } }}
 
 covall:
-    just python=python3.9 covcleanup=false cov
     just python=python3.10 covcleanup=false cov
     just python=pypy3.10 covcleanup=false cov
     just python=python3.11 covcleanup=false cov
     just python=python3.12 covcleanup=false cov
     just python=python3.13 covcleanup=false cov
+    just python=python3.14 covcleanup=false cov
     uv run coverage combine
     uv run coverage report
     @rm .coverage*

docs/indepth.md

@@ -19,10 +19,6 @@ The new copy may be changed through the `copy` arguments, but will retain all ma
 
 ## Customizing Collection Unstructuring
 
-```{important}
-This feature is supported for Python 3.9 and later.
-```
-
 ```{tip}
 See [](customizing.md#customizing-collections) for a more modern and more powerful way of customizing collection handling.
 ```

pyproject.toml

@@ -44,15 +44,14 @@ dependencies = [
     "typing-extensions>=4.14.0",
     "exceptiongroup>=1.1.1; python_version < '3.11'",
 ]
-requires-python = ">=3.9"
+requires-python = ">=3.10"
 readme = "README.md"
 license = {text = "MIT"}
 keywords = ["attrs", "serialization", "dataclasses"]
 classifiers = [
     "Development Status :: 5 - Production/Stable",
     "Intended Audience :: Developers",
     "License :: OSI Approved :: MIT License",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
@@ -152,10 +151,14 @@ ignore = [
     "SIM300", # Yoda rocks in asserts
     "PGH003", # leave my type: ignores alone
     "B006",   # mutable argument defaults
+    "B905",   # zip strictness, too noisy
     "DTZ001", # datetimes in tests
     "DTZ006", # datetimes in tests
     "UP006",  # We support old typing constructs at runtime
+    "UP007",  # We support old typing constructs at runtime
     "UP035",  # We support old typing constructs at runtime
+    "UP038",  # Dubious rule
+    "UP045",  # We support old typing constructs at runtime
 ]
 
 [tool.ruff.lint.pyupgrade]

src/cattrs/_compat.py

@@ -208,10 +208,7 @@ def get_final_base(type) -> Optional[type]:
 OriginAbstractSet = AbcSet
 OriginMutableSet = AbcMutableSet
 
-signature = _signature
-
-if sys.version_info >= (3, 10):
-    signature = partial(_signature, eval_str=True)
+signature = partial(_signature, eval_str=True)
 
 
 try:
@@ -269,7 +266,7 @@ def get_newtype_base(typ: Any) -> Optional[type]:
 
     from typing import NotRequired, Required
 
-elif sys.version_info >= (3, 10):
+else:
     from typing import _UnionGenericAlias
 
     def is_union_type(obj):
@@ -291,27 +288,6 @@ def get_newtype_base(typ: Any) -> Optional[type]:
     else:
         from typing_extensions import NotRequired, Required
 
-else:
-    # 3.9
-    from typing import _UnionGenericAlias
-
-    from typing_extensions import NotRequired, Required
-
-    def is_union_type(obj):
-        return obj is Union or (
-            isinstance(obj, _UnionGenericAlias) and obj.__origin__ is Union
-        )
-
-    def get_newtype_base(typ: Any) -> Optional[type]:
-        supertype = getattr(typ, "__supertype__", None)
-        if (
-            supertype is not None
-            and getattr(typ, "__qualname__", "") == "NewType.<locals>.new_type"
-            and typ.__module__ in ("typing", "typing_extensions")
-        ):
-            return supertype
-        return None
-
 
 def get_notrequired_base(type) -> Union[Any, NothingType]:
     if is_annotated(type):

src/cattrs/gen/typeddicts.py

@@ -3,23 +3,12 @@
 import re
 import sys
 from collections.abc import Mapping
+from inspect import get_annotations
 from typing import TYPE_CHECKING, Any, Callable, Literal, TypeVar
 
 from attrs import NOTHING, Attribute
 from typing_extensions import _TypedDictMeta
 
-try:
-    from inspect import get_annotations
-
-    def get_annots(cl) -> dict[str, Any]:
-        return get_annotations(cl, eval_str=True)
-
-except ImportError:
-    # https://docs.python.org/3/howto/annotations.html#accessing-the-annotations-dict-of-an-object-in-python-3-9-and-older
-    def get_annots(cl) -> dict[str, Any]:
-        return cl.__dict__.get("__annotations__", {})
-
-
 from .._compat import (
     get_full_type_hints,
     get_notrequired_base,
@@ -50,6 +39,10 @@ def get_annots(cl) -> dict[str, Any]:
 T = TypeVar("T")
 
 
+def get_annots(cl) -> dict[str, Any]:
+    return get_annotations(cl, eval_str=True)
+
+
 def make_dict_unstructure_fn(
     cl: type[T],
     converter: BaseConverter,

src/cattrs/preconf/__init__.py

@@ -1,17 +1,11 @@
-import sys
 from datetime import datetime
 from enum import Enum
-from typing import Any, Callable, TypeVar, get_args
+from typing import Any, Callable, ParamSpec, TypeVar, get_args
 
 from .._compat import is_subclass
 from ..converters import Converter, UnstructureHook
 from ..fns import identity
 
-if sys.version_info[:2] < (3, 10):
-    from typing_extensions import ParamSpec
-else:
-    from typing import ParamSpec
-
 
 def validate_datetime(v, _):
     if not isinstance(v, datetime):