Merge branch 'master' into bugfix/2232-adopt-distutils-default

.bumpversion.cfg

 [bumpversion]
-current_version = 49.3.0
+current_version = 49.5.0
 commit = True
 tag = True
 

CHANGES.rst

+v49.5.0
+-------
+
+* #2306: When running as a PEP 517 backend, setuptools does not try to install
+  ``setup_requires`` itself. They are reported as build requirements for the
+  frontend to install.
+
+
+v49.4.0
+-------
+
+* #2310: Updated vendored packaging version to 20.4.
+
+
+v49.3.2
+-------
+
+* #2300: Improve the ``safe_version`` function documentation
+* #2297: Once again, in stubs prefer exec_module to the deprecated load_module.
+
+
+v49.3.1
+-------
+
+* #2316: Removed warning when ``distutils`` is imported before ``setuptools`` when ``distutils`` replacement is not enabled.
+
+
 v49.3.0
 -------
 

_distutils_hack/__init__.py

@@ -16,9 +16,12 @@ def warn_distutils_present():
         # https://foss.heptapod.net/pypy/pypy/-/blob/be829135bc0d758997b3566062999ee8b23872b4/lib-python/3/site.py#L250
         return
     warnings.warn(
-        "Distutils was imported before Setuptools. This usage is discouraged "
-        "and may exhibit undesirable behaviors or errors. Please use "
-        "Setuptools' objects directly or at least import Setuptools first.")
+        "Distutils was imported before Setuptools, but importing Setuptools "
+        "also replaces the `distutils` module in `sys.modules`. This may lead "
+        "to undesirable behaviors or errors. To avoid these issues, avoid "
+        "using distutils directly, ensure that setuptools is installed in the "
+        "traditional way (e.g. not an editable install), and/or make sure that "
+        "setuptools is always imported before distutils.")
 
 
 def clear_distutils():
@@ -56,8 +59,8 @@ def do_override():
     See https://github.com/pypa/setuptools/issues/417#issuecomment-392298401
     for more motivation.
     """
-    warn_distutils_present()
     if enabled():
+        warn_distutils_present()
         ensure_local_distutils()
 
 

changelog.d/2129.change.rst

+In pkg_resources, no longer detect any pathname ending in .egg as a Python egg. Now the path must be an unpacked egg or a zip file.

docs/pkg_resources.txt

@@ -1596,12 +1596,12 @@ Parsing Utilities
     See ``to_filename()``.
 
 ``safe_version(version)``
-    This will return the normalized form of any PEP 440 version, if the version
-    string is not PEP 440 compatible than it is similar to ``safe_name()``
-    except that spaces in the input become dots, and dots are allowed to exist
-    in the output.  As with ``safe_name()``, if you are generating a filename
-    from this you should replace any "-" characters in the output with
-    underscores.
+    This will return the normalized form of any PEP 440 version. If the version
+    string is not PEP 440 compatible, this function behaves similar to
+    ``safe_name()`` except that spaces in the input become dots, and dots are
+    allowed to exist in the output.  As with ``safe_name()``, if you are
+    generating a filename from this you should replace any "-" characters in
+    the output with underscores.
 
 ``safe_extra(extra)``
     Return a "safe" form of an extra's name, suitable for use in a requirement

docs/setuptools.txt

@@ -1988,11 +1988,11 @@ boilerplate code in some cases.
     include_package_data = True
     packages = find:
     scripts =
-      bin/first.py
-      bin/second.py
+        bin/first.py
+        bin/second.py
     install_requires =
-      requests
-      importlib; python_version == "2.6"
+        requests
+        importlib; python_version == "2.6"
 
     [options.package_data]
     * = *.txt, *.rst
@@ -2028,8 +2028,8 @@ Metadata and options are set in the config sections of the same name.
 
       [metadata]
       keywords =
-        one
-        two
+          one
+          two
 
 * In some cases, complex values can be provided in dedicated subsections for
   clarity.

pkg_resources/__init__.py

@@ -2056,7 +2056,10 @@ def find_on_path(importer, path_item, only=False):
         )
         return
 
-    entries = safe_listdir(path_item)
+    entries = (
+        os.path.join(path_item, child)
+        for child in safe_listdir(path_item)
+    )
 
     # for performance, before sorting by version,
     # screen entries for only those that will yield
@@ -2372,7 +2375,15 @@ def _is_egg_path(path):
     """
     Determine if given path appears to be an egg.
     """
-    return path.lower().endswith('.egg')
+    return _is_zip_egg(path) or _is_unpacked_egg(path)
+
+
+def _is_zip_egg(path):
+    return (
+        path.lower().endswith('.egg') and
+        os.path.isfile(path) and
+        zipfile.is_zipfile(path)
+    )
 
 
 def _is_unpacked_egg(path):
@@ -2380,7 +2391,7 @@ def _is_unpacked_egg(path):
     Determine if given path appears to be an unpacked egg.
     """
     return (
-        _is_egg_path(path) and
+        path.lower().endswith('.egg') and
         os.path.isfile(os.path.join(path, 'EGG-INFO', 'PKG-INFO'))
     )
 

pkg_resources/_vendor/packaging/__about__.py

@@ -18,10 +18,10 @@ __title__ = "packaging"
 __summary__ = "Core utilities for Python packages"
 __uri__ = "https://github.com/pypa/packaging"
 
-__version__ = "19.2"
+__version__ = "20.4"
 
 __author__ = "Donald Stufft and individual contributors"
 __email__ = "donald@stufft.io"
 
-__license__ = "BSD or Apache License, Version 2.0"
+__license__ = "BSD-2-Clause or Apache-2.0"
 __copyright__ = "Copyright 2014-2019 %s" % __author__

pkg_resources/_vendor/packaging/_compat.py

@@ -5,6 +5,11 @@ from __future__ import absolute_import, division, print_function
 
 import sys
 
+from ._typing import TYPE_CHECKING
+
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import Any, Dict, Tuple, Type
+
 
 PY2 = sys.version_info[0] == 2
 PY3 = sys.version_info[0] == 3
@@ -18,14 +23,16 @@ else:
 
 
 def with_metaclass(meta, *bases):
+    # type: (Type[Any], Tuple[Type[Any], ...]) -> Any
     """
     Create a base class with a metaclass.
     """
     # This requires a bit of explanation: the basic idea is to make a dummy
     # metaclass for one level of class instantiation that replaces itself with
     # the actual metaclass.
-    class metaclass(meta):
+    class metaclass(meta):  # type: ignore
         def __new__(cls, name, this_bases, d):
+            # type: (Type[Any], str, Tuple[Any], Dict[Any, Any]) -> Any
             return meta(name, bases, d)
 
     return type.__new__(metaclass, "temporary_class", (), {})

pkg_resources/_vendor/packaging/_structures.py

@@ -4,65 +4,83 @@
 from __future__ import absolute_import, division, print_function
 
 
-class Infinity(object):
+class InfinityType(object):
     def __repr__(self):
+        # type: () -> str
         return "Infinity"
 
     def __hash__(self):
+        # type: () -> int
         return hash(repr(self))
 
     def __lt__(self, other):
+        # type: (object) -> bool
         return False
 
     def __le__(self, other):
+        # type: (object) -> bool
         return False
 
     def __eq__(self, other):
+        # type: (object) -> bool
         return isinstance(other, self.__class__)
 
     def __ne__(self, other):
+        # type: (object) -> bool
         return not isinstance(other, self.__class__)
 
     def __gt__(self, other):
+        # type: (object) -> bool
         return True
 
     def __ge__(self, other):
+        # type: (object) -> bool
         return True
 
     def __neg__(self):
+        # type: (object) -> NegativeInfinityType
         return NegativeInfinity
 
 
-Infinity = Infinity()
+Infinity = InfinityType()
 
 
-class NegativeInfinity(object):
+class NegativeInfinityType(object):
     def __repr__(self):
+        # type: () -> str
         return "-Infinity"
 
     def __hash__(self):
+        # type: () -> int
         return hash(repr(self))
 
     def __lt__(self, other):
+        # type: (object) -> bool
         return True
 
     def __le__(self, other):
+        # type: (object) -> bool
         return True
 
     def __eq__(self, other):
+        # type: (object) -> bool
         return isinstance(other, self.__class__)
 
     def __ne__(self, other):
+        # type: (object) -> bool
         return not isinstance(other, self.__class__)
 
     def __gt__(self, other):
+        # type: (object) -> bool
         return False
 
     def __ge__(self, other):
+        # type: (object) -> bool
         return False
 
     def __neg__(self):
+        # type: (object) -> InfinityType
         return Infinity
 
 
-NegativeInfinity = NegativeInfinity()
+NegativeInfinity = NegativeInfinityType()

pkg_resources/_vendor/packaging/_typing.py

+"""For neatly implementing static typing in packaging.
+
+`mypy` - the static type analysis tool we use - uses the `typing` module, which
+provides core functionality fundamental to mypy's functioning.
+
+Generally, `typing` would be imported at runtime and used in that fashion -
+it acts as a no-op at runtime and does not have any run-time overhead by
+design.
+
+As it turns out, `typing` is not vendorable - it uses separate sources for
+Python 2/Python 3. Thus, this codebase can not expect it to be present.
+To work around this, mypy allows the typing import to be behind a False-y
+optional to prevent it from running at runtime and type-comments can be used
+to remove the need for the types to be accessible directly during runtime.
+
+This module provides the False-y guard in a nicely named fashion so that a
+curious maintainer can reach here to read this.
+
+In packaging, all static-typing related imports should be guarded as follows:
+
+    from packaging._typing import TYPE_CHECKING
+
+    if TYPE_CHECKING:
+        from typing import ...
+
+Ref: https://github.com/python/mypy/issues/3216
+"""
+
+__all__ = ["TYPE_CHECKING", "cast"]
+
+# The TYPE_CHECKING constant defined by the typing module is False at runtime
+# but True while type checking.
+if False:  # pragma: no cover
+    from typing import TYPE_CHECKING
+else:
+    TYPE_CHECKING = False
+
+# typing's cast syntax requires calling typing.cast at runtime, but we don't
+# want to import typing at runtime. Here, we inform the type checkers that
+# we're importing `typing.cast` as `cast` and re-implement typing.cast's
+# runtime behavior in a block that is ignored by type checkers.
+if TYPE_CHECKING:  # pragma: no cover
+    # not executed at runtime
+    from typing import cast
+else:
+    # executed at runtime
+    def cast(type_, value):  # noqa
+        return value

pkg_resources/_vendor/packaging/markers.py

@@ -13,8 +13,14 @@ from pkg_resources.extern.pyparsing import ZeroOrMore, Group, Forward, QuotedStr
 from pkg_resources.extern.pyparsing import Literal as L  # noqa
 
 from ._compat import string_types
+from ._typing import TYPE_CHECKING
 from .specifiers import Specifier, InvalidSpecifier
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import Any, Callable, Dict, List, Optional, Tuple, Union
+
+    Operator = Callable[[str, str], bool]
+
 
 __all__ = [
     "InvalidMarker",
@@ -46,30 +52,37 @@ class UndefinedEnvironmentName(ValueError):
 
 class Node(object):
     def __init__(self, value):
+        # type: (Any) -> None
         self.value = value
 
     def __str__(self):
+        # type: () -> str
         return str(self.value)
 
     def __repr__(self):
+        # type: () -> str
         return "<{0}({1!r})>".format(self.__class__.__name__, str(self))
 
     def serialize(self):
+        # type: () -> str
         raise NotImplementedError
 
 
 class Variable(Node):
     def serialize(self):
+        # type: () -> str
         return str(self)
 
 
 class Value(Node):
     def serialize(self):
+        # type: () -> str
         return '"{0}"'.format(self)
 
 
 class Op(Node):
     def serialize(self):
+        # type: () -> str
         return str(self)
 
 
@@ -85,13 +98,13 @@ VARIABLE = (
     | L("python_version")
     | L("sys_platform")
     | L("os_name")
-    | L("os.name")
+    | L("os.name")  # PEP-345
     | L("sys.platform")  # PEP-345
     | L("platform.version")  # PEP-345
     | L("platform.machine")  # PEP-345
     | L("platform.python_implementation")  # PEP-345
-    | L("python_implementation")  # PEP-345
-    | L("extra")  # undocumented setuptools legacy
+    | L("python_implementation")  # undocumented setuptools legacy
+    | L("extra")  # PEP-508
 )
 ALIASES = {
     "os.name": "os_name",
@@ -131,6 +144,7 @@ MARKER = stringStart + MARKER_EXPR + stringEnd
 
 
 def _coerce_parse_result(results):
+    # type: (Union[ParseResults, List[Any]]) -> List[Any]
     if isinstance(results, ParseResults):
         return [_coerce_parse_result(i) for i in results]
     else:
@@ -138,6 +152,8 @@ def _coerce_parse_result(results):
 
 
 def _format_marker(marker, first=True):
+    # type: (Union[List[str], Tuple[Node, ...], str], Optional[bool]) -> str
+
     assert isinstance(marker, (list, tuple, string_types))
 
     # Sometimes we have a structure like [[...]] which is a single item list
@@ -172,10 +188,11 @@ _operators = {
     "!=": operator.ne,
     ">=": operator.ge,
     ">": operator.gt,
-}
+}  # type: Dict[str, Operator]
 
 
 def _eval_op(lhs, op, rhs):
+    # type: (str, Op, str) -> bool
     try:
         spec = Specifier("".join([op.serialize(), rhs]))
     except InvalidSpecifier:
@@ -183,7 +200,7 @@ def _eval_op(lhs, op, rhs):
     else:
         return spec.contains(lhs)
 
-    oper = _operators.get(op.serialize())
+    oper = _operators.get(op.serialize())  # type: Optional[Operator]
     if oper is None:
         raise UndefinedComparison(
             "Undefined {0!r} on {1!r} and {2!r}.".format(op, lhs, rhs)
@@ -192,13 +209,18 @@ def _eval_op(lhs, op, rhs):
     return oper(lhs, rhs)
 
 
-_undefined = object()
+class Undefined(object):
+    pass
+
+
+_undefined = Undefined()
 
 
 def _get_env(environment, name):
-    value = environment.get(name, _undefined)
+    # type: (Dict[str, str], str) -> str
+    value = environment.get(name, _undefined)  # type: Union[str, Undefined]
 
-    if value is _undefined:
+    if isinstance(value, Undefined):
         raise UndefinedEnvironmentName(
             "{0!r} does not exist in evaluation environment.".format(name)
         )
@@ -207,7 +229,8 @@ def _get_env(environment, name):
 
 
 def _evaluate_markers(markers, environment):
-    groups = [[]]
+    # type: (List[Any], Dict[str, str]) -> bool
+    groups = [[]]  # type: List[List[bool]]
 
     for marker in markers:
         assert isinstance(marker, (list, tuple, string_types))
@@ -234,6 +257,7 @@ def _evaluate_markers(markers, environment):
 
 
 def format_full_version(info):
+    # type: (sys._version_info) -> str
     version = "{0.major}.{0.minor}.{0.micro}".format(info)
     kind = info.releaselevel
     if kind != "final":
@@ -242,9 +266,13 @@ def format_full_version(info):
 
 
 def default_environment():
+    # type: () -> Dict[str, str]
     if hasattr(sys, "implementation"):
-        iver = format_full_version(sys.implementation.version)
-        implementation_name = sys.implementation.name
+        # Ignoring the `sys.implementation` reference for type checking due to
+        # mypy not liking that the attribute doesn't exist in Python 2.7 when
+        # run with the `--py27` flag.
+        iver = format_full_version(sys.implementation.version)  # type: ignore
+        implementation_name = sys.implementation.name  # type: ignore
     else:
         iver = "0"
         implementation_name = ""
@@ -266,6 +294,7 @@ def default_environment():
 
 class Marker(object):
     def __init__(self, marker):
+        # type: (str) -> None
         try:
             self._markers = _coerce_parse_result(MARKER.parseString(marker))
         except ParseException as e:
@@ -275,12 +304,15 @@ class Marker(object):
             raise InvalidMarker(err_str)
 
     def __str__(self):
+        # type: () -> str
         return _format_marker(self._markers)
 
     def __repr__(self):
+        # type: () -> str
         return "<Marker({0!r})>".format(str(self))
 
     def evaluate(self, environment=None):
+        # type: (Optional[Dict[str, str]]) -> bool
         """Evaluate a marker.
 
         Return the boolean from evaluating the given marker against the

pkg_resources/_vendor/packaging/requirements.py

@@ -11,9 +11,13 @@ from pkg_resources.extern.pyparsing import ZeroOrMore, Word, Optional, Regex, Co
 from pkg_resources.extern.pyparsing import Literal as L  # noqa
 from pkg_resources.extern.six.moves.urllib import parse as urlparse
 
+from ._typing import TYPE_CHECKING
 from .markers import MARKER_EXPR, Marker
 from .specifiers import LegacySpecifier, Specifier, SpecifierSet
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import List
+
 
 class InvalidRequirement(ValueError):
     """
@@ -89,6 +93,7 @@ class Requirement(object):
     # TODO: Can we normalize the name and extra name?
 
     def __init__(self, requirement_string):
+        # type: (str) -> None
         try:
             req = REQUIREMENT.parseString(requirement_string)
         except ParseException as e:
@@ -116,7 +121,8 @@ class Requirement(object):
         self.marker = req.marker if req.marker else None
 
     def __str__(self):
-        parts = [self.name]
+        # type: () -> str
+        parts = [self.name]  # type: List[str]
 
         if self.extras:
             parts.append("[{0}]".format(",".join(sorted(self.extras))))
@@ -135,4 +141,5 @@ class Requirement(object):
         return "".join(parts)
 
     def __repr__(self):
+        # type: () -> str
         return "<Requirement({0!r})>".format(str(self))

pkg_resources/_vendor/packaging/utils.py

@@ -5,28 +5,36 @@ from __future__ import absolute_import, division, print_function
 
 import re
 
+from ._typing import TYPE_CHECKING, cast
 from .version import InvalidVersion, Version
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import NewType, Union
+
+    NormalizedName = NewType("NormalizedName", str)
 
 _canonicalize_regex = re.compile(r"[-_.]+")
 
 
 def canonicalize_name(name):
+    # type: (str) -> NormalizedName
     # This is taken from PEP 503.
-    return _canonicalize_regex.sub("-", name).lower()
+    value = _canonicalize_regex.sub("-", name).lower()
+    return cast("NormalizedName", value)
 
 
-def canonicalize_version(version):
+def canonicalize_version(_version):
+    # type: (str) -> Union[Version, str]
     """
-    This is very similar to Version.__str__, but has one subtle differences
+    This is very similar to Version.__str__, but has one subtle difference
     with the way it handles the release segment.
     """
 
     try:
-        version = Version(version)
+        version = Version(_version)
     except InvalidVersion:
         # Legacy versions cannot be normalized
-        return version
+        return _version
 
     parts = []
 

pkg_resources/_vendor/vendored.txt

-packaging==19.2
+packaging==20.4
 pyparsing==2.2.1
 six==1.10.0
 appdirs==1.4.3

setup.cfg

@@ -16,7 +16,7 @@ formats = zip
 
 [metadata]
 name = setuptools
-version = 49.3.0
+version = 49.5.0
 description = Easily download, build, install, upgrade, and uninstall Python packages
 author = Python Packaging Authority
 author_email = distutils-sig@python.org

setuptools/_vendor/packaging/__about__.py

@@ -18,10 +18,10 @@ __title__ = "packaging"
 __summary__ = "Core utilities for Python packages"
 __uri__ = "https://github.com/pypa/packaging"
 
-__version__ = "19.2"
+__version__ = "20.4"
 
 __author__ = "Donald Stufft and individual contributors"
 __email__ = "donald@stufft.io"
 
-__license__ = "BSD or Apache License, Version 2.0"
+__license__ = "BSD-2-Clause or Apache-2.0"
 __copyright__ = "Copyright 2014-2019 %s" % __author__

setuptools/_vendor/packaging/_compat.py

@@ -5,6 +5,11 @@ from __future__ import absolute_import, division, print_function
 
 import sys
 
+from ._typing import TYPE_CHECKING
+
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import Any, Dict, Tuple, Type
+
 
 PY2 = sys.version_info[0] == 2
 PY3 = sys.version_info[0] == 3
@@ -18,14 +23,16 @@ else:
 
 
 def with_metaclass(meta, *bases):
+    # type: (Type[Any], Tuple[Type[Any], ...]) -> Any
     """
     Create a base class with a metaclass.
     """
     # This requires a bit of explanation: the basic idea is to make a dummy
     # metaclass for one level of class instantiation that replaces itself with
     # the actual metaclass.
-    class metaclass(meta):
+    class metaclass(meta):  # type: ignore
         def __new__(cls, name, this_bases, d):
+            # type: (Type[Any], str, Tuple[Any], Dict[Any, Any]) -> Any
             return meta(name, bases, d)
 
     return type.__new__(metaclass, "temporary_class", (), {})

setuptools/_vendor/packaging/_structures.py

@@ -4,65 +4,83 @@
 from __future__ import absolute_import, division, print_function
 
 
-class Infinity(object):
+class InfinityType(object):
     def __repr__(self):
+        # type: () -> str
         return "Infinity"
 
     def __hash__(self):
+        # type: () -> int
         return hash(repr(self))
 
     def __lt__(self, other):
+        # type: (object) -> bool
         return False
 
     def __le__(self, other):
+        # type: (object) -> bool
         return False
 
     def __eq__(self, other):
+        # type: (object) -> bool
         return isinstance(other, self.__class__)
 
     def __ne__(self, other):
+        # type: (object) -> bool
         return not isinstance(other, self.__class__)
 
     def __gt__(self, other):
+        # type: (object) -> bool
         return True
 
     def __ge__(self, other):
+        # type: (object) -> bool
         return True
 
     def __neg__(self):
+        # type: (object) -> NegativeInfinityType
         return NegativeInfinity
 
 
-Infinity = Infinity()
+Infinity = InfinityType()
 
 
-class NegativeInfinity(object):
+class NegativeInfinityType(object):
     def __repr__(self):
+        # type: () -> str
         return "-Infinity"
 
     def __hash__(self):
+        # type: () -> int
         return hash(repr(self))
 
     def __lt__(self, other):
+        # type: (object) -> bool
         return True
 
     def __le__(self, other):
+        # type: (object) -> bool
         return True
 
     def __eq__(self, other):
+        # type: (object) -> bool
         return isinstance(other, self.__class__)
 
     def __ne__(self, other):
+        # type: (object) -> bool
         return not isinstance(other, self.__class__)
 
     def __gt__(self, other):
+        # type: (object) -> bool
         return False
 
     def __ge__(self, other):
+        # type: (object) -> bool
         return False
 
     def __neg__(self):
+        # type: (object) -> InfinityType
         return Infinity
 
 
-NegativeInfinity = NegativeInfinity()
+NegativeInfinity = NegativeInfinityType()

setuptools/_vendor/packaging/_typing.py

+"""For neatly implementing static typing in packaging.
+
+`mypy` - the static type analysis tool we use - uses the `typing` module, which
+provides core functionality fundamental to mypy's functioning.
+
+Generally, `typing` would be imported at runtime and used in that fashion -
+it acts as a no-op at runtime and does not have any run-time overhead by
+design.
+
+As it turns out, `typing` is not vendorable - it uses separate sources for
+Python 2/Python 3. Thus, this codebase can not expect it to be present.
+To work around this, mypy allows the typing import to be behind a False-y
+optional to prevent it from running at runtime and type-comments can be used
+to remove the need for the types to be accessible directly during runtime.
+
+This module provides the False-y guard in a nicely named fashion so that a
+curious maintainer can reach here to read this.
+
+In packaging, all static-typing related imports should be guarded as follows:
+
+    from packaging._typing import TYPE_CHECKING
+
+    if TYPE_CHECKING:
+        from typing import ...
+
+Ref: https://github.com/python/mypy/issues/3216
+"""
+
+__all__ = ["TYPE_CHECKING", "cast"]
+
+# The TYPE_CHECKING constant defined by the typing module is False at runtime
+# but True while type checking.
+if False:  # pragma: no cover
+    from typing import TYPE_CHECKING
+else:
+    TYPE_CHECKING = False
+
+# typing's cast syntax requires calling typing.cast at runtime, but we don't
+# want to import typing at runtime. Here, we inform the type checkers that
+# we're importing `typing.cast` as `cast` and re-implement typing.cast's
+# runtime behavior in a block that is ignored by type checkers.
+if TYPE_CHECKING:  # pragma: no cover
+    # not executed at runtime
+    from typing import cast
+else:
+    # executed at runtime
+    def cast(type_, value):  # noqa
+        return value

setuptools/_vendor/packaging/markers.py

@@ -13,8 +13,14 @@ from setuptools.extern.pyparsing import ZeroOrMore, Group, Forward, QuotedString
 from setuptools.extern.pyparsing import Literal as L  # noqa
 
 from ._compat import string_types
+from ._typing import TYPE_CHECKING
 from .specifiers import Specifier, InvalidSpecifier
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import Any, Callable, Dict, List, Optional, Tuple, Union
+
+    Operator = Callable[[str, str], bool]
+
 
 __all__ = [
     "InvalidMarker",
@@ -46,30 +52,37 @@ class UndefinedEnvironmentName(ValueError):
 
 class Node(object):
     def __init__(self, value):
+        # type: (Any) -> None
         self.value = value
 
     def __str__(self):
+        # type: () -> str
         return str(self.value)
 
     def __repr__(self):
+        # type: () -> str
         return "<{0}({1!r})>".format(self.__class__.__name__, str(self))
 
     def serialize(self):
+        # type: () -> str
         raise NotImplementedError
 
 
 class Variable(Node):
     def serialize(self):
+        # type: () -> str
         return str(self)
 
 
 class Value(Node):
     def serialize(self):
+        # type: () -> str
         return '"{0}"'.format(self)
 
 
 class Op(Node):
     def serialize(self):
+        # type: () -> str
         return str(self)
 
 
@@ -85,13 +98,13 @@ VARIABLE = (
     | L("python_version")
     | L("sys_platform")
     | L("os_name")
-    | L("os.name")
+    | L("os.name")  # PEP-345
     | L("sys.platform")  # PEP-345
     | L("platform.version")  # PEP-345
     | L("platform.machine")  # PEP-345
     | L("platform.python_implementation")  # PEP-345
-    | L("python_implementation")  # PEP-345
-    | L("extra")  # undocumented setuptools legacy
+    | L("python_implementation")  # undocumented setuptools legacy
+    | L("extra")  # PEP-508
 )
 ALIASES = {
     "os.name": "os_name",
@@ -131,6 +144,7 @@ MARKER = stringStart + MARKER_EXPR + stringEnd
 
 
 def _coerce_parse_result(results):
+    # type: (Union[ParseResults, List[Any]]) -> List[Any]
     if isinstance(results, ParseResults):
         return [_coerce_parse_result(i) for i in results]
     else:
@@ -138,6 +152,8 @@ def _coerce_parse_result(results):
 
 
 def _format_marker(marker, first=True):
+    # type: (Union[List[str], Tuple[Node, ...], str], Optional[bool]) -> str
+
     assert isinstance(marker, (list, tuple, string_types))
 
     # Sometimes we have a structure like [[...]] which is a single item list
@@ -172,10 +188,11 @@ _operators = {
     "!=": operator.ne,
     ">=": operator.ge,
     ">": operator.gt,
-}
+}  # type: Dict[str, Operator]
 
 
 def _eval_op(lhs, op, rhs):
+    # type: (str, Op, str) -> bool
     try:
         spec = Specifier("".join([op.serialize(), rhs]))
     except InvalidSpecifier:
@@ -183,7 +200,7 @@ def _eval_op(lhs, op, rhs):
     else:
         return spec.contains(lhs)
 
-    oper = _operators.get(op.serialize())
+    oper = _operators.get(op.serialize())  # type: Optional[Operator]
     if oper is None:
         raise UndefinedComparison(
             "Undefined {0!r} on {1!r} and {2!r}.".format(op, lhs, rhs)
@@ -192,13 +209,18 @@ def _eval_op(lhs, op, rhs):
     return oper(lhs, rhs)
 
 
-_undefined = object()
+class Undefined(object):
+    pass
+
+
+_undefined = Undefined()
 
 
 def _get_env(environment, name):
-    value = environment.get(name, _undefined)
+    # type: (Dict[str, str], str) -> str
+    value = environment.get(name, _undefined)  # type: Union[str, Undefined]
 
-    if value is _undefined:
+    if isinstance(value, Undefined):
         raise UndefinedEnvironmentName(
             "{0!r} does not exist in evaluation environment.".format(name)
         )
@@ -207,7 +229,8 @@ def _get_env(environment, name):
 
 
 def _evaluate_markers(markers, environment):
-    groups = [[]]
+    # type: (List[Any], Dict[str, str]) -> bool
+    groups = [[]]  # type: List[List[bool]]
 
     for marker in markers:
         assert isinstance(marker, (list, tuple, string_types))
@@ -234,6 +257,7 @@ def _evaluate_markers(markers, environment):
 
 
 def format_full_version(info):
+    # type: (sys._version_info) -> str
     version = "{0.major}.{0.minor}.{0.micro}".format(info)
     kind = info.releaselevel
     if kind != "final":
@@ -242,9 +266,13 @@ def format_full_version(info):
 
 
 def default_environment():
+    # type: () -> Dict[str, str]
     if hasattr(sys, "implementation"):
-        iver = format_full_version(sys.implementation.version)
-        implementation_name = sys.implementation.name
+        # Ignoring the `sys.implementation` reference for type checking due to
+        # mypy not liking that the attribute doesn't exist in Python 2.7 when
+        # run with the `--py27` flag.
+        iver = format_full_version(sys.implementation.version)  # type: ignore
+        implementation_name = sys.implementation.name  # type: ignore
     else:
         iver = "0"
         implementation_name = ""
@@ -266,6 +294,7 @@ def default_environment():
 
 class Marker(object):
     def __init__(self, marker):
+        # type: (str) -> None
         try:
             self._markers = _coerce_parse_result(MARKER.parseString(marker))
         except ParseException as e:
@@ -275,12 +304,15 @@ class Marker(object):
             raise InvalidMarker(err_str)
 
     def __str__(self):
+        # type: () -> str
         return _format_marker(self._markers)
 
     def __repr__(self):
+        # type: () -> str
         return "<Marker({0!r})>".format(str(self))
 
     def evaluate(self, environment=None):
+        # type: (Optional[Dict[str, str]]) -> bool
         """Evaluate a marker.
 
         Return the boolean from evaluating the given marker against the

setuptools/_vendor/packaging/requirements.py

@@ -11,9 +11,13 @@ from setuptools.extern.pyparsing import ZeroOrMore, Word, Optional, Regex, Combi
 from setuptools.extern.pyparsing import Literal as L  # noqa
 from setuptools.extern.six.moves.urllib import parse as urlparse
 
+from ._typing import TYPE_CHECKING
 from .markers import MARKER_EXPR, Marker
 from .specifiers import LegacySpecifier, Specifier, SpecifierSet
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import List
+
 
 class InvalidRequirement(ValueError):
     """
@@ -89,6 +93,7 @@ class Requirement(object):
     # TODO: Can we normalize the name and extra name?
 
     def __init__(self, requirement_string):
+        # type: (str) -> None
         try:
             req = REQUIREMENT.parseString(requirement_string)
         except ParseException as e:
@@ -116,7 +121,8 @@ class Requirement(object):
         self.marker = req.marker if req.marker else None
 
     def __str__(self):
-        parts = [self.name]
+        # type: () -> str
+        parts = [self.name]  # type: List[str]
 
         if self.extras:
             parts.append("[{0}]".format(",".join(sorted(self.extras))))
@@ -135,4 +141,5 @@ class Requirement(object):
         return "".join(parts)
 
     def __repr__(self):
+        # type: () -> str
         return "<Requirement({0!r})>".format(str(self))

setuptools/_vendor/packaging/utils.py

@@ -5,28 +5,36 @@ from __future__ import absolute_import, division, print_function
 
 import re
 
+from ._typing import TYPE_CHECKING, cast
 from .version import InvalidVersion, Version
 
+if TYPE_CHECKING:  # pragma: no cover
+    from typing import NewType, Union
+
+    NormalizedName = NewType("NormalizedName", str)
 
 _canonicalize_regex = re.compile(r"[-_.]+")
 
 
 def canonicalize_name(name):
+    # type: (str) -> NormalizedName
     # This is taken from PEP 503.
-    return _canonicalize_regex.sub("-", name).lower()
+    value = _canonicalize_regex.sub("-", name).lower()
+    return cast("NormalizedName", value)
 
 
-def canonicalize_version(version):
+def canonicalize_version(_version):
+    # type: (str) -> Union[Version, str]
     """
-    This is very similar to Version.__str__, but has one subtle differences
+    This is very similar to Version.__str__, but has one subtle difference
     with the way it handles the release segment.
     """
 
     try:
-        version = Version(version)
+        version = Version(_version)
     except InvalidVersion:
         # Legacy versions cannot be normalized
-        return version
+        return _version
 
     parts = []
 

setuptools/_vendor/vendored.txt

-packaging==19.2
+packaging==20.4
 pyparsing==2.2.1
 six==1.10.0
 ordered-set==3.1.1

setuptools/build_meta.py

@@ -75,6 +75,22 @@ class Distribution(setuptools.dist.Distribution):
             distutils.core.Distribution = orig
 
 
+@contextlib.contextmanager
+def no_install_setup_requires():
+    """Temporarily disable installing setup_requires
+
+    Under PEP 517, the backend reports build dependencies to the frontend,
+    and the frontend is responsible for ensuring they're installed.
+    So setuptools (acting as a backend) should not try to install them.
+    """
+    orig = setuptools._install_setup_requires
+    setuptools._install_setup_requires = lambda attrs: None
+    try:
+        yield
+    finally:
+        setuptools._install_setup_requires = orig
+
+
 def _to_str(s):
     """
     Convert a filename to a string (on Python 2, explicitly
@@ -154,7 +170,8 @@ class _BuildMetaBackend(object):
                                          config_settings=None):
         sys.argv = sys.argv[:1] + ['dist_info', '--egg-base',
                                    _to_str(metadata_directory)]
-        self.run_setup()
+        with no_install_setup_requires():
+            self.run_setup()
 
         dist_info_directory = metadata_directory
         while True:
@@ -194,7 +211,8 @@ class _BuildMetaBackend(object):
             sys.argv = (sys.argv[:1] + setup_command +
                         ['--dist-dir', tmp_dist_dir] +
                         config_settings["--global-option"])
-            self.run_setup()
+            with no_install_setup_requires():
+                self.run_setup()
 
             result_basename = _file_with_extension(
                 tmp_dist_dir, result_extension)

setuptools/command/bdist_egg.py

@@ -55,11 +55,12 @@ def write_stub(resource, pyfile):
     _stub_template = textwrap.dedent("""
         def __bootstrap__():
             global __bootstrap__, __loader__, __file__
-            import sys, pkg_resources
-            from importlib.machinery import ExtensionFileLoader
+            import sys, pkg_resources, importlib.util
             __file__ = pkg_resources.resource_filename(__name__, %r)
             __loader__ = None; del __bootstrap__, __loader__
-            ExtensionFileLoader(__name__,__file__).load_module()
+            spec = importlib.util.spec_from_file_location(__name__,__file__)
+            mod = importlib.util.module_from_spec(spec)
+            spec.loader.exec_module(mod)
         __bootstrap__()
         """).lstrip()
     with open(pyfile, 'w') as f:

setuptools/command/build_ext.py

@@ -254,8 +254,8 @@ class build_ext(_build_ext):
                 '\n'.join([
                     "def __bootstrap__():",
                     "   global __bootstrap__, __file__, __loader__",
-                    "   import sys, os, pkg_resources" + if_dl(", dl"),
-                    "   from importlib.machinery import ExtensionFileLoader",
+                    "   import sys, os, pkg_resources, importlib.util" +
+                    if_dl(", dl"),
                     "   __file__ = pkg_resources.resource_filename"
                     "(__name__,%r)"
                     % os.path.basename(ext._file_name),
@@ -267,8 +267,10 @@ class build_ext(_build_ext):
                     "   try:",
                     "     os.chdir(os.path.dirname(__file__))",
                     if_dl("     sys.setdlopenflags(dl.RTLD_NOW)"),
-                    "     ExtensionFileLoader(__name__,",
-                    "                         __file__).load_module()",
+                    "     spec = importlib.util.spec_from_file_location(",
+                    "                __name__, __file__)",
+                    "     mod = importlib.util.module_from_spec(spec)",
+                    "     spec.loader.exec_module(mod)",
                     "   finally:",
                     if_dl("     sys.setdlopenflags(old_flags)"),
                     "     os.chdir(old_dir)",

setuptools/tests/test_build_meta.py

@@ -380,7 +380,7 @@ class TestBuildMetaBackend:
                 setup(
                     name="qux",
                     version="0.0.0",
-                    py_modules=["hello.py"],
+                    py_modules=["hello"],
                     setup_requires={setup_literal},
                 )
             """).format(setup_literal=setup_literal),
@@ -407,6 +407,35 @@ class TestBuildMetaBackend:
 
         assert expected == sorted(actual)
 
+    def test_dont_install_setup_requires(self, tmpdir_cwd):
+        files = {
+            'setup.py': DALS("""
+                        from setuptools import setup
+
+                        setup(
+                            name="qux",
+                            version="0.0.0",
+                            py_modules=["hello"],
+                            setup_requires=["does-not-exist >99"],
+                        )
+                    """),
+            'hello.py': DALS("""
+                    def run():
+                        print('hello')
+                    """),
+        }
+
+        build_files(files)
+
+        build_backend = self.get_build_backend()
+
+        dist_dir = os.path.abspath('pip-dist-info')
+        os.makedirs(dist_dir)
+
+        # does-not-exist can't be satisfied, so if it attempts to install
+        # setup_requires, it will fail.
+        build_backend.prepare_metadata_for_build_wheel(dist_dir)
+
     _sys_argv_0_passthrough = {
         'setup.py': DALS("""
             import os