[PEP 771]

pyproject.toml

@@ -174,6 +174,7 @@ keywords = "setuptools.dist:Distribution._finalize_setup_keywords"
 eager_resources = "setuptools.dist:assert_string_list"
 namespace_packages = "setuptools.dist:check_nsp"
 extras_require = "setuptools.dist:check_extras"
+default_extras_require = "setuptools.dist:check_default_extras_require"
 install_requires = "setuptools.dist:check_requirements"
 setup_requires = "setuptools.dist:check_requirements"
 python_requires = "setuptools.dist:check_specifier"

setuptools/_core_metadata.py

@@ -28,7 +28,7 @@
 def get_metadata_version(self):
     mv = getattr(self, 'metadata_version', None)
     if mv is None:
-        mv = Version('2.2')
+        mv = Version('2.5')
         self.metadata_version = mv
     return mv
 
@@ -223,6 +223,9 @@ def _write_requirements(self, file):
     for req in _reqs.parse(self.install_requires):
         file.write(f"Requires-Dist: {req}\n")
 
+    for req in _reqs.parse(self.default_extras_require):
+        file.write(f"Default-Extra: {req}\n")
+
     processed_extras = {}
     for augmented_extra, reqs in self.extras_require.items():
         # Historically, setuptools allows "augmented extras": `<extra>:<condition>`
@@ -311,6 +314,7 @@ def _distribution_fullname(name: str, version: str) -> str:
     "project-url": "project_urls",
     "provides": "provides",
     # "provides-dist": "provides_dist",  # NOT USED
+    "default-extra": "default_extras_require",
     "provides-extra": "extras_require",
     "requires": "requires",
     "requires-dist": "install_requires",

setuptools/_vendor/importlib_metadata/_adapters.py

@@ -15,6 +15,7 @@ class Message(email.message.Message):
                 'Platform',
                 'Project-URL',
                 'Provides-Dist',
+                'Default-Extra'
                 'Provides-Extra',
                 'Requires-Dist',
                 'Requires-External',

setuptools/_vendor/packaging/metadata.py

@@ -132,6 +132,9 @@ class RawMetadata(TypedDict, total=False):
     license_expression: str
     license_files: list[str]
 
+    # Metadata 2.5 - PEP 771
+    default_extra: list[str]
+
 
 _STRING_FIELDS = {
     "author",
@@ -253,6 +256,7 @@ def _get_payload(msg: email.message.Message, source: bytes | str) -> str:
     "author-email": "author_email",
     "classifier": "classifiers",
     "description": "description",
+    "default-extra": "default_extra",
     "description-content-type": "description_content_type",
     "download-url": "download_url",
     "dynamic": "dynamic",
@@ -463,8 +467,8 @@ def parse_email(data: bytes | str) -> tuple[RawMetadata, dict[str, list[str]]]:
 
 
 # Keep the two values in sync.
-_VALID_METADATA_VERSIONS = ["1.0", "1.1", "1.2", "2.1", "2.2", "2.3", "2.4"]
-_MetadataVersion = Literal["1.0", "1.1", "1.2", "2.1", "2.2", "2.3", "2.4"]
+_VALID_METADATA_VERSIONS = ["1.0", "1.1", "1.2", "2.1", "2.2", "2.3", "2.4", "2.5"]
+_MetadataVersion = Literal["1.0", "1.1", "1.2", "2.1", "2.2", "2.3", "2.4", "2.5"]
 
 _REQUIRED_ATTRS = frozenset(["metadata_version", "name", "version"])
 
@@ -861,3 +865,9 @@ def from_email(cls, data: bytes | str, *, validate: bool = True) -> Metadata:
     """``Provides`` (deprecated)"""
     obsoletes: _Validator[list[str] | None] = _Validator(added="1.1")
     """``Obsoletes`` (deprecated)"""
+    # PEP 771 lets us define a default `extras_require` if none is passed by the
+    # user.
+    default_extra: _Validator[list[utils.NormalizedName] | None] = _Validator(
+        added="2.5",
+    )
+    """:external:ref:`core-metadata-default-extra`"""

setuptools/_vendor/wheel/metadata.py

@@ -142,12 +142,12 @@ def generate_requirements(
 
 def pkginfo_to_metadata(egg_info_path: str, pkginfo_path: str) -> Message:
     """
-    Convert .egg-info directory with PKG-INFO to the Metadata 2.1 format
+    Convert .egg-info directory with PKG-INFO to the Metadata 2.5 format
     """
     with open(pkginfo_path, encoding="utf-8") as headers:
         pkg_info = Parser().parse(headers)
 
-    pkg_info.replace_header("Metadata-Version", "2.1")
+    pkg_info.replace_header("Metadata-Version", "2.5")
     # Those will be regenerated from `requires.txt`.
     del pkg_info["Provides-Extra"]
     del pkg_info["Requires-Dist"]

setuptools/config/_apply_pyprojecttoml.py

@@ -226,6 +226,13 @@ def _dependencies(dist: Distribution, val: list, _root_dir: StrPath | None):
     dist.install_requires = val
 
 
+def _default_optional_dependencies(dist: Distribution, val: dict, _root_dir: StrPath | None):
+    if getattr(dist, "default_extras_require", None):
+        msg = "`default_extras_require` overwritten in `pyproject.toml` (default-optional-dependencies)"
+        SetuptoolsWarning.emit(msg)
+    dist.default_extras_require = val
+
+
 def _optional_dependencies(dist: Distribution, val: dict, _root_dir: StrPath | None):
     if getattr(dist, "extras_require", None):
         msg = "`extras_require` overwritten in `pyproject.toml` (optional-dependencies)"
@@ -396,6 +403,7 @@ def _acessor(obj):
     "urls": _project_urls,
     "dependencies": _dependencies,
     "optional_dependencies": _optional_dependencies,
+    "default_optional_dependencies": _default_optional_dependencies,
     "requires_python": _python_requires,
 }
 
@@ -441,6 +449,7 @@ def _acessor(obj):
     "scripts": _get_previous_scripts,
     "gui-scripts": _get_previous_gui_scripts,
     "dependencies": _attrgetter("install_requires"),
+    "default-optional-dependencies": _attrgetter("default_extras_require"),
     "optional-dependencies": _attrgetter("extras_require"),
 }
 
@@ -458,6 +467,7 @@ def _acessor(obj):
     "scripts": _static.EMPTY_DICT,
     "gui-scripts": _static.EMPTY_DICT,
     "dependencies": _static.EMPTY_LIST,
+    "default-optional-dependencies": _static.EMPTY_LIST,
     "optional-dependencies": _static.EMPTY_DICT,
 }
 

setuptools/config/_validate_pyproject/extra_validations.py

@@ -24,6 +24,13 @@ class RedefiningStaticFieldAsDynamic(ValidationError):
     )
 
 
+class IncludedDependencyGroupMustExist(ValidationError):
+    _DESC = """An included dependency group must exist and must not be cyclic.
+    """
+    __doc__ = _DESC
+    _URL = "https://peps.python.org/pep-0735/"
+
+
 def validate_project_dynamic(pyproject: T) -> T:
     project_table = pyproject.get("project", {})
     dynamic = project_table.get("dynamic", [])
@@ -49,4 +56,27 @@ def validate_project_dynamic(pyproject: T) -> T:
     return pyproject
 
 
-EXTRA_VALIDATIONS = (validate_project_dynamic,)
+def validate_include_depenency(pyproject: T) -> T:
+    dependency_groups = pyproject.get("dependency-groups", {})
+    for key, value in dependency_groups.items():
+        for each in value:
+            if (
+                isinstance(each, dict)
+                and (include_group := each.get("include-group"))
+                and include_group not in dependency_groups
+            ):
+                raise IncludedDependencyGroupMustExist(
+                    message=f"The included dependency group {include_group} doesn't exist",
+                    value=each,
+                    name=f"data.dependency_groups.{key}",
+                    definition={
+                        "description": cleandoc(IncludedDependencyGroupMustExist._DESC),
+                        "see": IncludedDependencyGroupMustExist._URL,
+                    },
+                    rule="PEP 735",
+                )
+    # TODO: check for `include-group` cycles (can be conditional to graphlib)
+    return pyproject
+
+
+EXTRA_VALIDATIONS = (validate_project_dynamic, validate_include_depenency)

setuptools/config/_validate_pyproject/formats.py

@@ -164,12 +164,15 @@ class _TroveClassifier:
     """
 
     downloaded: typing.Union[None, "Literal[False]", typing.Set[str]]
+    """
+    None => not cached yet
+    False => unavailable
+    set => cached values
+    """
 
     def __init__(self) -> None:
         self.downloaded = None
         self._skip_download = False
-        # None => not cached yet
-        # False => cache not available
         self.__name__ = "trove_classifier"  # Emulate a public function
 
     def _disable_download(self) -> None:
@@ -351,7 +354,7 @@ def python_entrypoint_reference(value: str) -> bool:
         obj = rest
 
     module_parts = module.split(".")
-    identifiers = _chain(module_parts, obj.split(".")) if rest else module_parts
+    identifiers = _chain(module_parts, obj.split(".")) if rest else iter(module_parts)
     return all(python_identifier(i.strip()) for i in identifiers)
 
 
@@ -373,3 +376,27 @@ def uint(value: builtins.int) -> bool:
 def int(value: builtins.int) -> bool:
     r"""Signed 64-bit integer (:math:`-2^{63} \leq x < 2^{63}`)"""
     return -(2**63) <= value < 2**63
+
+
+try:
+    from packaging import licenses as _licenses
+
+    def SPDX(value: str) -> bool:
+        """See :ref:`PyPA's License-Expression specification
+        <pypa:core-metadata-license-expression>` (added in :pep:`639`).
+        """
+        try:
+            _licenses.canonicalize_license_expression(value)
+            return True
+        except _licenses.InvalidLicenseExpression:
+            return False
+
+except ImportError:  # pragma: no cover
+    _logger.warning(
+        "Could not find an up-to-date installation of `packaging`. "
+        "License expressions might not be validated. "
+        "To enforce validation, please install `packaging>=24.2`."
+    )
+
+    def SPDX(value: str) -> bool:
+        return True

setuptools/config/pyprojecttoml.py

@@ -249,6 +249,7 @@ def _expand_all_dynamic(self, dist: Distribution, package_dir: Mapping[str, str]
             "gui-scripts",
             "classifiers",
             "dependencies",
+            "default-optional-dependencies",
             "optional-dependencies",
         )
         # `_obtain` functions are assumed to raise appropriate exceptions/warnings.
@@ -263,6 +264,7 @@ def _expand_all_dynamic(self, dist: Distribution, package_dir: Mapping[str, str]
             readme=self._obtain_readme(dist),
             classifiers=self._obtain_classifiers(dist),
             dependencies=self._obtain_dependencies(dist),
+            default_optional_dependencies=self._obtain_default_optional_dependencies(dist),
             optional_dependencies=self._obtain_optional_dependencies(dist),
         )
         # `None` indicates there is nothing in `tool.setuptools.dynamic` but the value
@@ -370,6 +372,15 @@ def _obtain_dependencies(self, dist: Distribution):
                 return _parse_requirements_list(value)
         return None
 
+    def _obtain_default_optional_dependencies(self, dist: Distribution):
+        if "default-optional-dependencies" in self.dynamic:
+            value = self._obtain(dist, "default-optional-dependencies", {})
+            if value:
+                return _parse_requirements_list(value)
+        assert "extras_require" in dist.__dict__
+        assert "default_extras_require" in dist.__dict__
+        return None
+
     def _obtain_optional_dependencies(self, dist: Distribution):
         if "optional-dependencies" not in self.dynamic:
             return None

setuptools/config/setuptools.schema.json

@@ -222,6 +222,7 @@
         "description": {"$ref": "#/definitions/file-directive"},
         "entry-points": {"$ref": "#/definitions/file-directive"},
         "dependencies": {"$ref": "#/definitions/file-directive-for-dependencies"},
+        "default-optional-dependencies": {"$ref": "#/definitions/attr-directive"},
         "optional-dependencies": {
           "type": "object",
           "propertyNames": {"type": "string", "format": "pep508-identifier"},

setuptools/dist.py

@@ -132,6 +132,17 @@ def check_nsp(dist, attr, value):
         )
 
 
+def check_default_extras_require(dist, attr, value):
+    """Verify that extras_require mapping is valid"""
+    try:
+        assert isinstance(value, (list, tuple))
+        assert all(isinstance(val, str) for val in value)
+    except AssertionError as e:
+        raise DistutilsSetupError(
+            "'default_extras_require' must be a a list whose values are strings."
+        ) from e
+
+
 def check_extras(dist, attr, value):
     """Verify that extras_require mapping is valid"""
     try:
@@ -292,6 +303,7 @@ class Distribution(_Distribution):
         'license_files': lambda: None,
         'install_requires': list,
         'extras_require': dict,
+        'default_extras_require': list,
     }
 
     # Used by build_py, editable_wheel and install_lib commands for legacy namespaces
@@ -314,7 +326,11 @@ def __init__(self, attrs: MutableMapping[str, Any] | None = None) -> None:
             vars(self).setdefault(ep.name, None)
 
         metadata_only = set(self._DISTUTILS_UNSUPPORTED_METADATA)
-        metadata_only -= {"install_requires", "extras_require"}
+        metadata_only -= {
+            "install_requires",
+            "extras_require",
+            "default_extras_require",
+        }
         dist_attrs = {k: v for k, v in attrs.items() if k not in metadata_only}
         _Distribution.__init__(self, dist_attrs)
 
@@ -380,6 +396,7 @@ def _finalize_requires(self):
         self._normalize_requires()
         self.metadata.install_requires = self.install_requires
         self.metadata.extras_require = self.extras_require
+        self.metadata.default_extras_require = self.default_extras_require
 
         if self.extras_require:
             for extra in self.extras_require.keys():
@@ -392,6 +409,7 @@ def _normalize_requires(self):
         """Make sure requirement-related attributes exist and are normalized"""
         install_requires = getattr(self, "install_requires", None) or []
         extras_require = getattr(self, "extras_require", None) or {}
+        default_extras_require = getattr(self, "default_extras_require", None) or []
 
         # Preserve the "static"-ness of values parsed from config files
         list_ = _static.List if _static.is_static(install_requires) else list
@@ -402,6 +420,17 @@ def _normalize_requires(self):
             (k, list(map(str, _reqs.parse(v or [])))) for k, v in extras_require.items()
         )
 
+        self.default_extras_require = []
+        for extra in default_extras_require:
+            if extra not in self.extras_require:
+                raise ValueError(
+                    f"The default-extra `{extra}` does not exists in `extras_require`."
+                )
+            self.default_extras_require.append(extra)
+
+        list_ = _static.List if _static.is_static(default_extras_require) else list
+        self.default_extras_require = list_(self.default_extras_require)
+
     def _finalize_license_files(self) -> None:
         """Compute names of all license files which should be included."""
         license_files: list[str] | None = self.metadata.license_files