from __future__ import annotations
import re
from collections.abc import Iterator, Set
_WHEEL_FILENAME_REGEX = re.compile(
r'(?P<distribution>.+)-(?P<version>.+)'
r'(-(?P<build_tag>.+))?-(?P<python_tag>.+)'
r'-(?P<abi_tag>.+)-(?P<platform_tag>.+)\.whl'
)
def check_dependency(
req_string: str, ancestral_req_strings: tuple[str, ...] = (), parent_extras: Set[str] = frozenset()
) -> Iterator[tuple[str, ...]]:
"""
Verify that a dependency and all of its dependencies are met.
:param req_string: Requirement string
:param parent_extras: Extras (eg. "test" in myproject[test])
:yields: Unmet dependencies
"""
import packaging.requirements
from ._compat import importlib
req = packaging.requirements.Requirement(req_string)
normalised_req_string = str(req)
# ``Requirement`` doesn't implement ``__eq__`` so we cannot compare reqs for
# equality directly but the string representation is stable.
if normalised_req_string in ancestral_req_strings:
# cyclical dependency, already checked.
return
if req.marker:
extras = frozenset(('',)).union(parent_extras)
# a requirement can have multiple extras but ``evaluate`` can
# only check one at a time.
if all(not req.marker.evaluate(environment={'extra': e}) for e in extras):
# if the marker conditions are not met, we pretend that the
# dependency is satisfied.
return
try:
dist = importlib.metadata.distribution(req.name)
except importlib.metadata.PackageNotFoundError:
# dependency is not installed in the environment.
yield (*ancestral_req_strings, normalised_req_string)
else:
if req.specifier and not req.specifier.contains(dist.version, prereleases=True):
# the installed version is incompatible.
yield (*ancestral_req_strings, normalised_req_string)
elif dist.requires:
for other_req_string in dist.requires:
# yields transitive dependencies that are not satisfied.
yield from check_dependency(other_req_string, (*ancestral_req_strings, normalised_req_string), req.extras)
def parse_wheel_filename(filename: str) -> re.Match[str] | None:
return _WHEEL_FILENAME_REGEX.match(filename)
