Generate distutils-stubs on install

build_with_distutils_stubs.py

@@ -0,0 +1,74 @@
+"""Generate distutils stub files inside the source directory before packaging.
+We have to do this as a custom build backend for PEP 660 editable installs.
+Doing it this way also allows us to point local type-checkers to types/distutils,
+overriding the stdlib types even on Python < 3.12."""
+
+from __future__ import annotations
+
+import os
+import shutil
+from pathlib import Path
+
+from setuptools._path import StrPath
+from setuptools.build_meta import *  # noqa: F403 # expose everything
+from setuptools.build_meta import (
+    _ConfigSettings,
+    build_editable as _build_editable,
+    build_sdist as _build_sdist,
+    build_wheel as _build_wheel,
+)
+
+_vendored_distutils_path = Path(__file__).parent / "setuptools" / "_distutils"
+_distutils_stubs_path = Path(__file__).parent / "distutils-stubs"
+
+
+def _regenerate_distutils_stubs() -> None:
+    shutil.rmtree(_distutils_stubs_path, ignore_errors=True)
+    _distutils_stubs_path.mkdir(parents=True)
+    (_distutils_stubs_path / ".gitignore").write_text("*")
+    (_distutils_stubs_path / "ruff.toml").write_text('[lint]\nignore = ["F403"]')
+    (_distutils_stubs_path / "py.typed").write_text("\n")
+    for path in _vendored_distutils_path.rglob("*.py"):
+        relative_path = path.relative_to(_vendored_distutils_path)
+        if "tests" in relative_path.parts:
+            continue
+        stub_path = _distutils_stubs_path / relative_path.with_suffix(".pyi")
+        stub_path.parent.mkdir(parents=True, exist_ok=True)
+        module = "setuptools._distutils." + str(relative_path.with_suffix("")).replace(
+            os.sep, "."
+        ).removesuffix(".__init__")
+        if str(relative_path) == "__init__.py":
+            # Work around python/mypy#18775
+            stub_path.write_text("""\
+from typing import Final
+
+__version__: Final[str]
+""")
+        else:
+            stub_path.write_text(f"from {module} import *\n")
+
+
+def build_wheel(  # type: ignore[no-redef]
+    wheel_directory: StrPath,
+    config_settings: _ConfigSettings = None,
+    metadata_directory: StrPath | None = None,
+) -> str:
+    _regenerate_distutils_stubs()
+    return _build_wheel(wheel_directory, config_settings, metadata_directory)
+
+
+def build_sdist(  # type: ignore[no-redef]
+    sdist_directory: StrPath,
+    config_settings: _ConfigSettings = None,
+) -> str:
+    _regenerate_distutils_stubs()
+    return _build_sdist(sdist_directory, config_settings)
+
+
+def build_editable(  # type: ignore[no-redef]
+    wheel_directory: StrPath,
+    config_settings: _ConfigSettings = None,
+    metadata_directory: StrPath | None = None,
+) -> str:
+    _regenerate_distutils_stubs()
+    return _build_editable(wheel_directory, config_settings, metadata_directory)

mypy.ini

@@ -5,7 +5,7 @@
 strict = False
 
 # Early opt-in even when strict = False
-# warn_unused_ignores = True # Disabled until we have distutils stubs for Python 3.12+
+warn_unused_ignores = True
 warn_redundant_casts = True
 enable_error_code = ignore-without-code
 
@@ -48,14 +48,6 @@ disable_error_code =
 [mypy-pkg_resources.tests.*]
 disable_error_code = import-not-found
 
-# - distutils doesn't exist on Python 3.12, unfortunately, this means typing
-#   will be missing for subclasses of distutils on Python 3.12 until either:
-#     - support for `SETUPTOOLS_USE_DISTUTILS=stdlib` is dropped (#3625)
-#       for setuptools to import `_distutils` directly
-#     - or non-stdlib distutils typings are exposed
-[mypy-distutils.*]
-ignore_missing_imports = True
-
 #  - wheel: does not intend on exposing a programmatic API https://github.com/pypa/wheel/pull/610#issuecomment-2081687671
 [mypy-wheel.*]
 follow_untyped_imports = True

newsfragments/4861.feature.rst

@@ -0,0 +1 @@
+``setuptools`` now provide its own ``distutils-stubs`` instead of relying on typeshed -- by :user:`Avasam`

pyproject.toml

@@ -1,6 +1,6 @@
 [build-system]
 requires = []
-build-backend = "setuptools.build_meta"
+build-backend = "build_with_distutils_stubs"
 backend-path = ["."]
 
 [project]
@@ -202,6 +202,7 @@ include-package-data = true
 include = [
 	"setuptools*",
 	"pkg_resources*",
+	"distutils-stubs*",
 	"_distutils_hack*",
 ]
 exclude = [

pyrightconfig.json

@@ -12,6 +12,8 @@
 	],
 	// Our testing setup doesn't allow passing CLI arguments, so local devs have to set this manually.
 	// "pythonVersion": "3.9",
+	// Allow using distutils-stubs on Python 3.12+
+	"reportMissingModuleSource": false,
 	// For now we don't mind if mypy's `type: ignore` comments accidentally suppresses pyright issues
 	"enableTypeIgnoreComments": true,
 	"typeCheckingMode": "basic",

setuptools/__init__.py

@@ -1,9 +1,4 @@
 """Extensions to the 'distutils' for large or complex distributions"""
-# mypy: disable_error_code=override
-# Command.reinitialize_command has an extra **kw param that distutils doesn't have
-# Can't disable on the exact line because distutils doesn't exists on Python 3.12
-# and mypy isn't aware of distutils_hack, causing distutils.core.Command to be Any,
-# and a [unused-ignore] to be raised on 3.12+
 
 from __future__ import annotations
 
@@ -224,7 +219,7 @@ def reinitialize_command(
     ) -> _Command:
         cmd = _Command.reinitialize_command(self, command, reinit_subcommands)
         vars(cmd).update(kw)
-        return cmd  # pyright: ignore[reportReturnType] # pypa/distutils#307
+        return cmd
 
     @abstractmethod
     def initialize_options(self) -> None:

setuptools/build_meta.py

@@ -91,11 +91,11 @@ def patch(cls):
         for the duration of this context.
         """
         orig = distutils.core.Distribution
-        distutils.core.Distribution = cls  # type: ignore[misc] # monkeypatching
+        distutils.core.Distribution = cls
         try:
             yield
         finally:
-            distutils.core.Distribution = orig  # type: ignore[misc] # monkeypatching
+            distutils.core.Distribution = orig
 
 
 @contextlib.contextmanager

setuptools/command/build_ext.py

@@ -248,7 +248,7 @@ def setup_shlib_compiler(self):
             compiler.set_link_objects(self.link_objects)
 
         # hack so distutils' build_extension() builds a library instead
-        compiler.link_shared_object = link_shared_object.__get__(compiler)  # type: ignore[method-assign]
+        compiler.link_shared_object = link_shared_object.__get__(compiler)
 
     def get_export_symbols(self, ext):
         if isinstance(ext, Library):

setuptools/command/build_py.py

@@ -48,7 +48,7 @@ def finalize_options(self):
         if 'data_files' in self.__dict__:
             del self.__dict__['data_files']
 
-    def copy_file(  # type: ignore[override] # No overload, no bytes support
+    def copy_file(
         self,
         infile: StrPath,
         outfile: StrPathT,
@@ -135,7 +135,7 @@ def find_data_files(self, package, src_dir):
         )
         return self.exclude_data_files(package, src_dir, files)
 
-    def get_outputs(self, include_bytecode: bool = True) -> list[str]:  # type: ignore[override] # Using a real boolean instead of 0|1
+    def get_outputs(self, include_bytecode: bool = True) -> list[str]:
         """See :class:`setuptools.commands.build.SubCommand`"""
         if self.editable_mode:
             return list(self.get_output_mapping().keys())

setuptools/command/install_lib.py

@@ -95,10 +95,9 @@ def copy_tree(
         self,
         infile: StrPath,
         outfile: str,
-        # override: Using actual booleans
-        preserve_mode: bool = True,  # type: ignore[override]
-        preserve_times: bool = True,  # type: ignore[override]
-        preserve_symlinks: bool = False,  # type: ignore[override]
+        preserve_mode: bool = True,
+        preserve_times: bool = True,
+        preserve_symlinks: bool = False,
         level: object = 1,
     ) -> list[str]:
         assert preserve_mode

setuptools/command/sdist.py

@@ -50,7 +50,7 @@ class sdist(orig.sdist):
     ]
 
     distribution: Distribution  # override distutils.dist.Distribution with setuptools.dist.Distribution
-    negative_opt: ClassVar[dict[str, str]] = {}
+    negative_opt: ClassVar[dict[str, str]] = {}  # type: ignore[misc] # TODO: Fix upstream
 
     README_EXTENSIONS = ['', '.rst', '.txt', '.md']
     READMES = tuple(f'README{ext}' for ext in README_EXTENSIONS)

setuptools/command/setopt.py

@@ -37,7 +37,7 @@ def edit_config(filename, settings, dry_run=False):
     """
     log.debug("Reading configuration from %s", filename)
     opts = configparser.RawConfigParser()
-    opts.optionxform = lambda optionstr: optionstr  # type: ignore[method-assign] # overriding method
+    opts.optionxform = lambda optionstr: optionstr
     _cfg_read_utf8_with_fallback(opts, filename)
 
     for section, options in settings.items():

setuptools/config/setupcfg.py

@@ -17,7 +17,7 @@
 from collections import defaultdict
 from collections.abc import Iterable, Iterator
 from functools import partial, wraps
-from typing import TYPE_CHECKING, Any, Callable, ClassVar, Generic, TypeVar, cast
+from typing import TYPE_CHECKING, Any, Callable, ClassVar, Generic, TypeVar
 
 from packaging.markers import default_environment as marker_env
 from packaging.requirements import InvalidRequirement, Requirement
@@ -101,8 +101,7 @@ def _apply(
     filenames = [*other_files, filepath]
 
     try:
-        # TODO: Temporary cast until mypy 1.12 is released with upstream fixes from typeshed
-        _Distribution.parse_config_files(dist, filenames=cast(list[str], filenames))
+        _Distribution.parse_config_files(dist, filenames=filenames)
         handlers = parse_configuration(
             dist, dist.command_options, ignore_option_errors=ignore_option_errors
         )

setuptools/dist.py

@@ -727,7 +727,7 @@ def fetch_build_egg(self, req):
 
         return fetch_build_egg(self, req)
 
-    def get_command_class(self, command: str) -> type[distutils.cmd.Command]:  # type: ignore[override] # Not doing complex overrides yet
+    def get_command_class(self, command: str) -> type[distutils.cmd.Command]:
         """Pluggable version of get_command_class()"""
         if command in self.cmdclass:
             return self.cmdclass[command]

setuptools/errors.py

@@ -30,15 +30,15 @@
 BaseError = _distutils_errors.DistutilsError
 
 
-class InvalidConfigError(OptionError):  # type: ignore[valid-type, misc] # distutils imports are `Any` on python 3.12+
+class InvalidConfigError(OptionError):
     """Error used for invalid configurations."""
 
 
-class RemovedConfigError(OptionError):  # type: ignore[valid-type, misc] # distutils imports are `Any` on python 3.12+
+class RemovedConfigError(OptionError):
     """Error used for configurations that were deprecated and removed."""
 
 
-class RemovedCommandError(BaseError, RuntimeError):  # type: ignore[valid-type, misc] # distutils imports are `Any` on python 3.12+
+class RemovedCommandError(BaseError, RuntimeError):
     """Error used for commands that have been removed in setuptools.
 
     Since ``setuptools`` is built on ``distutils``, simply removing a command
@@ -48,7 +48,7 @@ class RemovedCommandError(BaseError, RuntimeError):  # type: ignore[valid-type,
     """
 
 
-class PackageDiscoveryError(BaseError, RuntimeError):  # type: ignore[valid-type, misc] # distutils imports are `Any` on python 3.12+
+class PackageDiscoveryError(BaseError, RuntimeError):
     """Impossible to perform automatic discovery of packages and/or modules.
 
     The current project layout or given discovery options can lead to problems when

setuptools/extension.py

@@ -151,12 +151,7 @@ def __init__(
         # The *args is needed for compatibility as calls may use positional
         # arguments. py_limited_api may be set only via keyword.
         self.py_limited_api = py_limited_api
-        super().__init__(
-            name,
-            sources,  # type: ignore[arg-type] # Vendored version of setuptools supports PathLike
-            *args,
-            **kw,
-        )
+        super().__init__(name, sources, *args, **kw)
 
     def _convert_pyx_sources_to_lang(self):
         """

setuptools/logging.py

@@ -32,7 +32,7 @@ def configure() -> None:
         # and then loaded again when patched,
         # implying: id(distutils.log) != id(distutils.dist.log).
         # Make sure the same module object is used everywhere:
-        distutils.dist.log = distutils.log
+        distutils.dist.log = distutils.log  # type: ignore[assignment]
 
 
 def set_threshold(level: int) -> int:

setuptools/monkey.py

@@ -73,7 +73,7 @@ def patch_all():
     import setuptools
 
     # we can't patch distutils.cmd, alas
-    distutils.core.Command = setuptools.Command  # type: ignore[misc,assignment] # monkeypatching
+    distutils.core.Command = setuptools.Command
 
     _patch_distribution_metadata()
 
@@ -82,8 +82,8 @@ def patch_all():
         module.Distribution = setuptools.dist.Distribution
 
     # Install the patched Extension
-    distutils.core.Extension = setuptools.extension.Extension  # type: ignore[misc,assignment] # monkeypatching
-    distutils.extension.Extension = setuptools.extension.Extension  # type: ignore[misc,assignment] # monkeypatching
+    distutils.core.Extension = setuptools.extension.Extension
+    distutils.extension.Extension = setuptools.extension.Extension
     if 'distutils.command.build_ext' in sys.modules:
         sys.modules[
             'distutils.command.build_ext'