Config changes to use our custom stubs

Author: Avasam

Diff for: 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
 
@@ -18,6 +18,9 @@ disable_error_code =
 
 ## local
 
+# Use our custom stubs for distutils
+mypy_path = $MYPY_CONFIG_FILE_DIR/typings
+
 # CI should test for all versions, local development gets hints for oldest supported
 # But our testing setup doesn't allow passing CLI arguments, so local devs have to set this manually.
 # python_version = 3.8
@@ -48,17 +51,10 @@ 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.*]
 ignore_missing_imports = True
+
 # - The following are not marked as py.typed:
 #  - jaraco: Since mypy 1.12, the root name of the untyped namespace package gets called-out too
 #  - jaraco.develop: https://github.com/jaraco/jaraco.develop/issues/22

Diff for: pyproject.toml

@@ -133,6 +133,8 @@ type = [
 
 	# local
 
+	# Referenced in distutils-stubs
+	"types-docutils",
 	# pin mypy version so a new version doesn't suddenly cause the CI to fail,
 	# until types-setuptools is removed from typeshed.
 	# For help with static-typing issues, or mypy update, ping @Avasam 
@@ -203,6 +205,8 @@ include-package-data = true
 include = [
 	"setuptools*",
 	"pkg_resources*",
+	# TODO: Include distutils stubs with package once we're confident in them
+	# "typings/distutils-stubs",
 	"_distutils_hack*",
 ]
 exclude = [

Diff for: pyrightconfig.json

@@ -12,6 +12,8 @@
 	],
 	// Our testing setup doesn't allow passing CLI arguments, so local devs have to set this manually.
 	// "pythonVersion": "3.8",
+	// 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",

Diff for: ruff.toml

@@ -34,6 +34,9 @@ ignore = [
 	# Only enforcing return type annotations for public functions
 	"ANN202", # missing-return-type-private-function
 	"ANN204", # missing-return-type-special-method
+	# Typeshed doesn't want complex or non-literal defaults for maintenance and testing reasons.
+	# This doesn't affect us, let's have more complete stubs.
+	"PYI011", # typed-argument-default-in-stub
 
 	# https://docs.astral.sh/ruff/formatter/#conflicting-lint-rules
 	"W191",

Diff for: 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
 
@@ -226,7 +221,7 @@ def reinitialize_command(
     ) -> _Command:
         cmd = _Command.reinitialize_command(self, command, reinit_subcommands)
         vars(cmd).update(kw)
-        return cmd
+        return cmd  # pyright: ignore[reportReturnType] # pypa/distutils#307
 
     @abstractmethod
     def initialize_options(self) -> None:

Diff for: setuptools/command/build_py.py

@@ -50,7 +50,7 @@ def finalize_options(self):
             del self.__dict__['data_files']
         self.__updated_files = []
 
-    def copy_file(  # type: ignore[override] # No overload, str support only
+    def copy_file(
         self,
         infile: StrPath,
         outfile: StrPath,
@@ -143,7 +143,7 @@ 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())

Diff for: setuptools/command/install.py

@@ -161,4 +161,5 @@ def do_egg_install(self):
 # XXX Python 3.1 doesn't see _nc if this is inside the class
 install.sub_commands = [
     cmd for cmd in orig.install.sub_commands if cmd[0] not in install._nc
-] + install.new_commands
+] + install.new_commands  # type: ignore[operator]
+# TODO: Type sub_commands/new_commands to avoid variance issues in pypa/distutils (like python/typeshed#11951)

Diff for: 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 and preserve_times and not preserve_symlinks

Diff for: setuptools/command/sdist.py

@@ -50,10 +50,12 @@ class sdist(orig.sdist):
     ]
 
     distribution: Distribution  # override distutils.dist.Distribution with setuptools.dist.Distribution
-    negative_opt: ClassVar[dict[str, str]] = {}
+    # TODO: Mark class-level mutables as ClassVars in pypa/distutils (like python/typeshed#12403)
+    negative_opt: ClassVar[dict[str, str]] = {}  # type: ignore[assignment]
 
     README_EXTENSIONS = ['', '.rst', '.txt', '.md']
-    READMES = tuple('README{0}'.format(ext) for ext in README_EXTENSIONS)
+    # TODO: Mark class-level mutables as ClassVars in pypa/distutils (like python/typeshed#12403)
+    READMES = tuple('README{0}'.format(ext) for ext in README_EXTENSIONS)  # type: ignore[assignment]
 
     def run(self):
         self.run_command('egg_info')

Diff for: setuptools/config/setupcfg.py

@@ -24,10 +24,8 @@
     Generic,
     Iterable,
     Iterator,
-    List,
     Tuple,
     TypeVar,
-    cast,
 )
 
 from packaging.markers import default_environment as marker_env
@@ -112,8 +110,7 @@ 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
         )

Diff for: 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

Diff for: 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):
         """