1 files changed, 275 insertions, 0 deletions
diff --git a/third_party/python/setuptools/setuptools/config/_validate_pyproject/formats.py b/third_party/python/setuptools/setuptools/config/_validate_pyproject/formats.py
new file mode 100644
index 0000000000..486d52602c
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+++ b/third_party/python/setuptools/setuptools/config/_validate_pyproject/formats.py
@@ -0,0 +1,275 @@
+import logging
+import os
+import re
+import string
+import typing
+from itertools import chain as _chain
+
+if typing.TYPE_CHECKING:
+    from typing_extensions import Literal
+
+_logger = logging.getLogger(__name__)
+
+# -------------------------------------------------------------------------------------
+# PEP 440
+
+VERSION_PATTERN = r"""
+    v?
+    (?:
+        (?:(?P<epoch>[0-9]+)!)?                           # epoch
+        (?P<release>[0-9]+(?:\.[0-9]+)*)                  # release segment
+        (?P<pre>                                          # pre-release
+            [-_\.]?
+            (?P<pre_l>(a|b|c|rc|alpha|beta|pre|preview))
+            [-_\.]?
+            (?P<pre_n>[0-9]+)?
+        )?
+        (?P<post>                                         # post release
+            (?:-(?P<post_n1>[0-9]+))
+            |
+            (?:
+                [-_\.]?
+                (?P<post_l>post|rev|r)
+                [-_\.]?
+                (?P<post_n2>[0-9]+)?
+            )
+        )?
+        (?P<dev>                                          # dev release
+            [-_\.]?
+            (?P<dev_l>dev)
+            [-_\.]?
+            (?P<dev_n>[0-9]+)?
+        )?
+    )
+    (?:\+(?P<local>[a-z0-9]+(?:[-_\.][a-z0-9]+)*))?       # local version
+"""
+
+VERSION_REGEX = re.compile(r"^\s*" + VERSION_PATTERN + r"\s*$", re.X | re.I)
+
+
+def pep440(version: str) -> bool:
+    return VERSION_REGEX.match(version) is not None
+
+
+# -------------------------------------------------------------------------------------
+# PEP 508
+
+PEP508_IDENTIFIER_PATTERN = r"([A-Z0-9]|[A-Z0-9][A-Z0-9._-]*[A-Z0-9])"
+PEP508_IDENTIFIER_REGEX = re.compile(f"^{PEP508_IDENTIFIER_PATTERN}$", re.I)
+
+
+def pep508_identifier(name: str) -> bool:
+    return PEP508_IDENTIFIER_REGEX.match(name) is not None
+
+
+try:
+    try:
+        from packaging import requirements as _req
+    except ImportError:  # pragma: no cover
+        # let's try setuptools vendored version
+        from setuptools._vendor.packaging import requirements as _req  # type: ignore
+
+    def pep508(value: str) -> bool:
+        try:
+            _req.Requirement(value)
+            return True
+        except _req.InvalidRequirement:
+            return False
+
+except ImportError:  # pragma: no cover
+    _logger.warning(
+        "Could not find an installation of `packaging`. Requirements, dependencies and "
+        "versions might not be validated. "
+        "To enforce validation, please install `packaging`."
+    )
+
+    def pep508(value: str) -> bool:
+        return True
+
+
+def pep508_versionspec(value: str) -> bool:
+    """Expression that can be used to specify/lock versions (including ranges)"""
+    if any(c in value for c in (";", "]", "@")):
+        # In PEP 508:
+        # conditional markers, extras and URL specs are not included in the
+        # versionspec
+        return False
+    # Let's pretend we have a dependency called `requirement` with the given
+    # version spec, then we can re-use the pep508 function for validation:
+    return pep508(f"requirement{value}")
+
+
+# -------------------------------------------------------------------------------------
+# PEP 517
+
+
+def pep517_backend_reference(value: str) -> bool:
+    module, _, obj = value.partition(":")
+    identifiers = (i.strip() for i in _chain(module.split("."), obj.split(".")))
+    return all(python_identifier(i) for i in identifiers if i)
+
+
+# -------------------------------------------------------------------------------------
+# Classifiers - PEP 301
+
+
+def _download_classifiers() -> str:
+    import ssl
+    from email.message import Message
+    from urllib.request import urlopen
+
+    url = "https://pypi.org/pypi?:action=list_classifiers"
+    context = ssl.create_default_context()
+    with urlopen(url, context=context) as response:
+        headers = Message()
+        headers["content_type"] = response.getheader("content-type", "text/plain")
+        return response.read().decode(headers.get_param("charset", "utf-8"))
+
+
+class _TroveClassifier:
+    """The ``trove_classifiers`` package is the official way of validating classifiers,
+    however this package might not be always available.
+    As a workaround we can still download a list from PyPI.
+    We also don't want to be over strict about it, so simply skipping silently is an
+    option (classifiers will be validated anyway during the upload to PyPI).
+    """
+
+    downloaded: typing.Union[None, "Literal[False]", typing.Set[str]]
+
+    def __init__(self):
+        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):
+        # This is a private API. Only setuptools has the consent of using it.
+        self._skip_download = True
+
+    def __call__(self, value: str) -> bool:
+        if self.downloaded is False or self._skip_download is True:
+            return True
+
+        if os.getenv("NO_NETWORK") or os.getenv("VALIDATE_PYPROJECT_NO_NETWORK"):
+            self.downloaded = False
+            msg = (
+                "Install ``trove-classifiers`` to ensure proper validation. "
+                "Skipping download of classifiers list from PyPI (NO_NETWORK)."
+            )
+            _logger.debug(msg)
+            return True
+
+        if self.downloaded is None:
+            msg = (
+                "Install ``trove-classifiers`` to ensure proper validation. "
+                "Meanwhile a list of classifiers will be downloaded from PyPI."
+            )
+            _logger.debug(msg)
+            try:
+                self.downloaded = set(_download_classifiers().splitlines())
+            except Exception:
+                self.downloaded = False
+                _logger.debug("Problem with download, skipping validation")
+                return True
+
+        return value in self.downloaded or value.lower().startswith("private ::")
+
+
+try:
+    from trove_classifiers import classifiers as _trove_classifiers
+
+    def trove_classifier(value: str) -> bool:
+        return value in _trove_classifiers or value.lower().startswith("private ::")
+
+except ImportError:  # pragma: no cover
+    trove_classifier = _TroveClassifier()
+
+
+# -------------------------------------------------------------------------------------
+# Stub packages - PEP 561
+
+
+def pep561_stub_name(value: str) -> bool:
+    top, *children = value.split(".")
+    if not top.endswith("-stubs"):
+        return False
+    return python_module_name(".".join([top[: -len("-stubs")], *children]))
+
+
+# -------------------------------------------------------------------------------------
+# Non-PEP related
+
+
+def url(value: str) -> bool:
+    from urllib.parse import urlparse
+
+    try:
+        parts = urlparse(value)
+        if not parts.scheme:
+            _logger.warning(
+                "For maximum compatibility please make sure to include a "
+                "`scheme` prefix in your URL (e.g. 'http://'). "
+                f"Given value: {value}"
+            )
+            if not (value.startswith("/") or value.startswith("\\") or "@" in value):
+                parts = urlparse(f"http://{value}")
+
+        return bool(parts.scheme and parts.netloc)
+    except Exception:
+        return False
+
+
+# https://packaging.python.org/specifications/entry-points/
+ENTRYPOINT_PATTERN = r"[^\[\s=]([^=]*[^\s=])?"
+ENTRYPOINT_REGEX = re.compile(f"^{ENTRYPOINT_PATTERN}$", re.I)
+RECOMMEDED_ENTRYPOINT_PATTERN = r"[\w.-]+"
+RECOMMEDED_ENTRYPOINT_REGEX = re.compile(f"^{RECOMMEDED_ENTRYPOINT_PATTERN}$", re.I)
+ENTRYPOINT_GROUP_PATTERN = r"\w+(\.\w+)*"
+ENTRYPOINT_GROUP_REGEX = re.compile(f"^{ENTRYPOINT_GROUP_PATTERN}$", re.I)
+
+
+def python_identifier(value: str) -> bool:
+    return value.isidentifier()
+
+
+def python_qualified_identifier(value: str) -> bool:
+    if value.startswith(".") or value.endswith("."):
+        return False
+    return all(python_identifier(m) for m in value.split("."))
+
+
+def python_module_name(value: str) -> bool:
+    return python_qualified_identifier(value)
+
+
+def python_entrypoint_group(value: str) -> bool:
+    return ENTRYPOINT_GROUP_REGEX.match(value) is not None
+
+
+def python_entrypoint_name(value: str) -> bool:
+    if not ENTRYPOINT_REGEX.match(value):
+        return False
+    if not RECOMMEDED_ENTRYPOINT_REGEX.match(value):
+        msg = f"Entry point `{value}` does not follow recommended pattern: "
+        msg += RECOMMEDED_ENTRYPOINT_PATTERN
+        _logger.warning(msg)
+    return True
+
+
+def python_entrypoint_reference(value: str) -> bool:
+    module, _, rest = value.partition(":")
+    if "[" in rest:
+        obj, _, extras_ = rest.partition("[")
+        if extras_.strip()[-1] != "]":
+            return False
+        extras = (x.strip() for x in extras_.strip(string.whitespace + "[]").split(","))
+        if not all(pep508_identifier(e) for e in extras):
+            return False
+        _logger.warning(f"`{value}` - using extras for entry points is not recommended")
+    else:
+        obj = rest
+
+    module_parts = module.split(".")
+    identifiers = _chain(module_parts, obj.split(".")) if rest else module_parts
+    return all(python_identifier(i.strip()) for i in identifiers)