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| DIR:/lib/python3.9/site-packages/pip/_internal/req/ |
| Current File : //lib/python3.9/site-packages/pip/_internal/req/req_set.py |
import logging
from collections import OrderedDict
from typing import Dict, Iterable, List, Optional, Tuple
from pip._vendor.packaging.utils import canonicalize_name
from pip._internal.exceptions import InstallationError
from pip._internal.models.wheel import Wheel
from pip._internal.req.req_install import InstallRequirement
from pip._internal.utils import compatibility_tags
logger = logging.getLogger(__name__)
class RequirementSet:
def __init__(self, check_supported_wheels: bool = True) -> None:
"""Create a RequirementSet."""
self.requirements: Dict[str, InstallRequirement] = OrderedDict()
self.check_supported_wheels = check_supported_wheels
self.unnamed_requirements: List[InstallRequirement] = []
def __str__(self) -> str:
requirements = sorted(
(req for req in self.requirements.values() if not req.comes_from),
key=lambda req: canonicalize_name(req.name or ""),
)
return " ".join(str(req.req) for req in requirements)
def __repr__(self) -> str:
requirements = sorted(
self.requirements.values(),
key=lambda req: canonicalize_name(req.name or ""),
)
format_string = "<{classname} object; {count} requirement(s): {reqs}>"
return format_string.format(
classname=self.__class__.__name__,
count=len(requirements),
reqs=", ".join(str(req.req) for req in requirements),
)
def add_unnamed_requirement(self, install_req: InstallRequirement) -> None:
assert not install_req.name
self.unnamed_requirements.append(install_req)
def add_named_requirement(self, install_req: InstallRequirement) -> None:
assert install_req.name
project_name = canonicalize_name(install_req.name)
self.requirements[project_name] = install_req
def add_requirement(
self,
install_req: InstallRequirement,
parent_req_name: Optional[str] = None,
extras_requested: Optional[Iterable[str]] = None,
) -> Tuple[List[InstallRequirement], Optional[InstallRequirement]]:
"""Add install_req as a requirement to install.
:param parent_req_name: The name of the requirement that needed this
added. The name is used because when multiple unnamed requirements
resolve to the same name, we could otherwise end up with dependency
links that point outside the Requirements set. parent_req must
already be added. Note that None implies that this is a user
supplied requirement, vs an inferred one.
:param extras_requested: an iterable of extras used to evaluate the
environment markers.
:return: Additional requirements to scan. That is either [] if
the requirement is not applicable, or [install_req] if the
requirement is applicable and has just been added.
"""
# If the markers do not match, ignore this requirement.
if not install_req.match_markers(extras_requested):
logger.info(
"Ignoring %s: markers '%s' don't match your environment",
install_req.name,
install_req.markers,
)
return [], None
# If the wheel is not supported, raise an error.
# Should check this after filtering out based on environment markers to
# allow specifying different wheels based on the environment/OS, in a
# single requirements file.
if install_req.link and install_req.link.is_wheel:
wheel = Wheel(install_req.link.filename)
tags = compatibility_tags.get_supported()
if self.check_supported_wheels and not wheel.supported(tags):
raise InstallationError(
"{} is not a supported wheel on this platform.".format(
wheel.filename
)
)
# This next bit is really a sanity check.
assert (
not install_req.user_supplied or parent_req_name is None
), "a user supplied req shouldn't have a parent"
# Unnamed requirements are scanned again and the requirement won't be
# added as a dependency until after scanning.
if not install_req.name:
self.add_unnamed_requirement(install_req)
return [install_req], None
try:
existing_req: Optional[InstallRequirement] = self.get_requirement(
install_req.name
)
except KeyError:
existing_req = None
has_conflicting_requirement = (
parent_req_name is None
and existing_req
and not existing_req.constraint
and existing_req.extras == install_req.extras
and existing_req.req
and install_req.req
and existing_req.req.specifier != install_req.req.specifier
)
if has_conflicting_requirement:
raise InstallationError(
"Double requirement given: {} (already in {}, name={!r})".format(
install_req, existing_req, install_req.name
)
)
# When no existing requirement exists, add the requirement as a
# dependency and it will be scanned again after.
if not existing_req:
self.add_named_requirement(install_req)
# We'd want to rescan this requirement later
return [install_req], install_req
# Assume there's no need to scan, and that we've already
# encountered this for scanning.
if install_req.constraint or not existing_req.constraint:
return [], existing_req
does_not_satisfy_constraint = install_req.link and not (
existing_req.link and install_req.link.path == existing_req.link.path
)
if does_not_satisfy_constraint:
raise InstallationError(
"Could not satisfy constraints for '{}': "
"installation from path or url cannot be "
"constrained to a version".format(install_req.name)
)
# If we're now installing a constraint, mark the existing
# object for real installation.
existing_req.constraint = False
# If we're now installing a user supplied requirement,
# mark the existing object as such.
if install_req.user_supplied:
existing_req.user_supplied = True
existing_req.extras = tuple(
sorted(set(existing_req.extras) | set(install_req.extras))
)
logger.debug(
"Setting %s extras to: %s",
existing_req,
existing_req.extras,
)
# Return the existing requirement for addition to the parent and
# scanning again.
return [existing_req], existing_req
def has_requirement(self, name: str) -> bool:
project_name = canonicalize_name(name)
return (
project_name in self.requirements
and not self.requirements[project_name].constraint
)
def get_requirement(self, name: str) -> InstallRequirement:
project_name = canonicalize_name(name)
if project_name in self.requirements:
return self.requirements[project_name]
raise KeyError(f"No project with the name {name!r}")
@property
def all_requirements(self) -> List[InstallRequirement]:
return self.unnamed_requirements + list(self.requirements.values())
|