JezK
Edit File: candidates.py
import logging import sys from typing import TYPE_CHECKING, Any, FrozenSet, Iterable, Optional, Tuple, Union, cast from pip._vendor.packaging.utils import NormalizedName, canonicalize_name from pip._vendor.packaging.version import Version from pip._internal.exceptions import ( HashError, InstallationSubprocessError, MetadataInconsistent, ) from pip._internal.metadata import BaseDistribution from pip._internal.models.link import Link, links_equivalent from pip._internal.models.wheel import Wheel from pip._internal.req.constructors import ( install_req_from_editable, install_req_from_line, ) from pip._internal.req.req_install import InstallRequirement from pip._internal.utils.direct_url_helpers import direct_url_from_link from pip._internal.utils.misc import normalize_version_info from .base import Candidate, CandidateVersion, Requirement, format_name if TYPE_CHECKING: from .factory import Factory logger = logging.getLogger(__name__) BaseCandidate = Union[ "AlreadyInstalledCandidate", "EditableCandidate", "LinkCandidate", ] # Avoid conflicting with the PyPI package "Python". REQUIRES_PYTHON_IDENTIFIER = cast(NormalizedName, "<Python from Requires-Python>") def as_base_candidate(candidate: Candidate) -> Optional[BaseCandidate]: """The runtime version of BaseCandidate.""" base_candidate_classes = ( AlreadyInstalledCandidate, EditableCandidate, LinkCandidate, ) if isinstance(candidate, base_candidate_classes): return candidate return None def make_install_req_from_link( link: Link, template: InstallRequirement ) -> InstallRequirement: assert not template.editable, "template is editable" if template.req: line = str(template.req) else: line = link.url ireq = install_req_from_line( line, user_supplied=template.user_supplied, comes_from=template.comes_from, use_pep517=template.use_pep517, isolated=template.isolated, constraint=template.constraint, options=dict( install_options=template.install_options, global_options=template.global_options, hashes=template.hash_options, ), config_settings=template.config_settings, ) ireq.original_link = template.original_link ireq.link = link return ireq def make_install_req_from_editable( link: Link, template: InstallRequirement ) -> InstallRequirement: assert template.editable, "template not editable" return install_req_from_editable( link.url, user_supplied=template.user_supplied, comes_from=template.comes_from, use_pep517=template.use_pep517, isolated=template.isolated, constraint=template.constraint, permit_editable_wheels=template.permit_editable_wheels, options=dict( install_options=template.install_options, global_options=template.global_options, hashes=template.hash_options, ), config_settings=template.config_settings, ) def _make_install_req_from_dist( dist: BaseDistribution, template: InstallRequirement ) -> InstallRequirement: if template.req: line = str(template.req) elif template.link: line = f"{dist.canonical_name} @ {template.link.url}" else: line = f"{dist.canonical_name}=={dist.version}" ireq = install_req_from_line( line, user_supplied=template.user_supplied, comes_from=template.comes_from, use_pep517=template.use_pep517, isolated=template.isolated, constraint=template.constraint, options=dict( install_options=template.install_options, global_options=template.global_options, hashes=template.hash_options, ), config_settings=template.config_settings, ) ireq.satisfied_by = dist return ireq class _InstallRequirementBackedCandidate(Candidate): """A candidate backed by an ``InstallRequirement``. This represents a package request with the target not being already in the environment, and needs to be fetched and installed. The backing ``InstallRequirement`` is responsible for most of the leg work; this class exposes appropriate information to the resolver. :param link: The link passed to the ``InstallRequirement``. The backing ``InstallRequirement`` will use this link to fetch the distribution. :param source_link: The link this candidate "originates" from. This is different from ``link`` when the link is found in the wheel cache. ``link`` would point to the wheel cache, while this points to the found remote link (e.g. from pypi.org). """ dist: BaseDistribution is_installed = False def __init__( self, link: Link, source_link: Link, ireq: InstallRequirement, factory: "Factory", name: Optional[NormalizedName] = None, version: Optional[CandidateVersion] = None, ) -> None: self._link = link self._source_link = source_link self._factory = factory self._ireq = ireq self._name = name self._version = version self.dist = self._prepare() def __str__(self) -> str: return f"{self.name} {self.version}" def __repr__(self) -> str: return "{class_name}({link!r})".format( class_name=self.__class__.__name__, link=str(self._link), ) def __hash__(self) -> int: return hash((self.__class__, self._link)) def __eq__(self, other: Any) -> bool: if isinstance(other, self.__class__): return links_equivalent(self._link, other._link) return False @property def source_link(self) -> Optional[Link]: return self._source_link @property def project_name(self) -> NormalizedName: """The normalised name of the project the candidate refers to""" if self._name is None: self._name = self.dist.canonical_name return self._name @property def name(self) -> str: return self.project_name @property def version(self) -> CandidateVersion: if self._version is None: self._version = self.dist.version return self._version def format_for_error(self) -> str: return "{} {} (from {})".format( self.name, self.version, self._link.file_path if self._link.is_file else self._link, ) def _prepare_distribution(self) -> BaseDistribution: raise NotImplementedError("Override in subclass") def _check_metadata_consistency(self, dist: BaseDistribution) -> None: """Check for consistency of project name and version of dist.""" if self._name is not None and self._name != dist.canonical_name: raise MetadataInconsistent( self._ireq, "name", self._name, dist.canonical_name, ) if self._version is not None and self._version != dist.version: raise MetadataInconsistent( self._ireq, "version", str(self._version), str(dist.version), ) def _prepare(self) -> BaseDistribution: try: dist = self._prepare_distribution() except HashError as e: # Provide HashError the underlying ireq that caused it. This # provides context for the resulting error message to show the # offending line to the user. e.req = self._ireq raise except InstallationSubprocessError as exc: # The output has been presented already, so don't duplicate it. exc.context = "See above for output." raise self._check_metadata_consistency(dist) return dist def iter_dependencies(self, with_requires: bool) -> Iterable[Optional[Requirement]]: requires = self.dist.iter_dependencies() if with_requires else () for r in requires: yield self._factory.make_requirement_from_spec(str(r), self._ireq) yield self._factory.make_requires_python_requirement(self.dist.requires_python) def get_install_requirement(self) -> Optional[InstallRequirement]: return self._ireq class LinkCandidate(_InstallRequirementBackedCandidate): is_editable = False def __init__( self, link: Link, template: InstallRequirement, factory: "Factory", name: Optional[NormalizedName] = None, version: Optional[CandidateVersion] = None, ) -> None: source_link = link cache_entry = factory.get_wheel_cache_entry(link, name) if cache_entry is not None: logger.debug("Using cached wheel link: %s", cache_entry.link) link = cache_entry.link ireq = make_install_req_from_link(link, template) assert ireq.link == link if ireq.link.is_wheel and not ireq.link.is_file: wheel = Wheel(ireq.link.filename) wheel_name = canonicalize_name(wheel.name) assert name == wheel_name, f"{name!r} != {wheel_name!r} for wheel" # Version may not be present for PEP 508 direct URLs if version is not None: wheel_version = Version(wheel.version) assert version == wheel_version, "{!r} != {!r} for wheel {}".format( version, wheel_version, name ) if cache_entry is not None: if cache_entry.persistent and template.link is template.original_link: ireq.original_link_is_in_wheel_cache = True if cache_entry.origin is not None: ireq.download_info = cache_entry.origin else: # Legacy cache entry that does not have origin.json. # download_info may miss the archive_info.hash field. ireq.download_info = direct_url_from_link( source_link, link_is_in_wheel_cache=cache_entry.persistent ) super().__init__( link=link, source_link=source_link, ireq=ireq, factory=factory, name=name, version=version, ) def _prepare_distribution(self) -> BaseDistribution: preparer = self._factory.preparer return preparer.prepare_linked_requirement(self._ireq, parallel_builds=True) class EditableCandidate(_InstallRequirementBackedCandidate): is_editable = True def __init__( self, link: Link, template: InstallRequirement, factory: "Factory", name: Optional[NormalizedName] = None, version: Optional[CandidateVersion] = None, ) -> None: super().__init__( link=link, source_link=link, ireq=make_install_req_from_editable(link, template), factory=factory, name=name, version=version, ) def _prepare_distribution(self) -> BaseDistribution: return self._factory.preparer.prepare_editable_requirement(self._ireq) class AlreadyInstalledCandidate(Candidate): is_installed = True source_link = None def __init__( self, dist: BaseDistribution, template: InstallRequirement, factory: "Factory", ) -> None: self.dist = dist self._ireq = _make_install_req_from_dist(dist, template) self._factory = factory # This is just logging some messages, so we can do it eagerly. # The returned dist would be exactly the same as self.dist because we # set satisfied_by in _make_install_req_from_dist. # TODO: Supply reason based on force_reinstall and upgrade_strategy. skip_reason = "already satisfied" factory.preparer.prepare_installed_requirement(self._ireq, skip_reason) def __str__(self) -> str: return str(self.dist) def __repr__(self) -> str: return "{class_name}({distribution!r})".format( class_name=self.__class__.__name__, distribution=self.dist, ) def __hash__(self) -> int: return hash((self.__class__, self.name, self.version)) def __eq__(self, other: Any) -> bool: if isinstance(other, self.__class__): return self.name == other.name and self.version == other.version return False @property def project_name(self) -> NormalizedName: return self.dist.canonical_name @property def name(self) -> str: return self.project_name @property def version(self) -> CandidateVersion: return self.dist.version @property def is_editable(self) -> bool: return self.dist.editable def format_for_error(self) -> str: return f"{self.name} {self.version} (Installed)" def iter_dependencies(self, with_requires: bool) -> Iterable[Optional[Requirement]]: if not with_requires: return for r in self.dist.iter_dependencies(): yield self._factory.make_requirement_from_spec(str(r), self._ireq) def get_install_requirement(self) -> Optional[InstallRequirement]: return None class ExtrasCandidate(Candidate): """A candidate that has 'extras', indicating additional dependencies. Requirements can be for a project with dependencies, something like foo[extra]. The extras don't affect the project/version being installed directly, but indicate that we need additional dependencies. We model that by having an artificial ExtrasCandidate that wraps the "base" candidate. The ExtrasCandidate differs from the base in the following ways: 1. It has a unique name, of the form foo[extra]. This causes the resolver to treat it as a separate node in the dependency graph. 2. When we're getting the candidate's dependencies, a) We specify that we want the extra dependencies as well. b) We add a dependency on the base candidate. See below for why this is needed. 3. We return None for the underlying InstallRequirement, as the base candidate will provide it, and we don't want to end up with duplicates. The dependency on the base candidate is needed so that the resolver can't decide that it should recommend foo[extra1] version 1.0 and foo[extra2] version 2.0. Having those candidates depend on foo=1.0 and foo=2.0 respectively forces the resolver to recognise that this is a conflict. """ def __init__( self, base: BaseCandidate, extras: FrozenSet[str], ) -> None: self.base = base self.extras = extras def __str__(self) -> str: name, rest = str(self.base).split(" ", 1) return "{}[{}] {}".format(name, ",".join(self.extras), rest) def __repr__(self) -> str: return "{class_name}(base={base!r}, extras={extras!r})".format( class_name=self.__class__.__name__, base=self.base, extras=self.extras, ) def __hash__(self) -> int: return hash((self.base, self.extras)) def __eq__(self, other: Any) -> bool: if isinstance(other, self.__class__): return self.base == other.base and self.extras == other.extras return False @property def project_name(self) -> NormalizedName: return self.base.project_name @property def name(self) -> str: """The normalised name of the project the candidate refers to""" return format_name(self.base.project_name, self.extras) @property def version(self) -> CandidateVersion: return self.base.version def format_for_error(self) -> str: return "{} [{}]".format( self.base.format_for_error(), ", ".join(sorted(self.extras)) ) @property def is_installed(self) -> bool: return self.base.is_installed @property def is_editable(self) -> bool: return self.base.is_editable @property def source_link(self) -> Optional[Link]: return self.base.source_link def iter_dependencies(self, with_requires: bool) -> Iterable[Optional[Requirement]]: factory = self.base._factory # Add a dependency on the exact base # (See note 2b in the class docstring) yield factory.make_requirement_from_candidate(self.base) if not with_requires: return # The user may have specified extras that the candidate doesn't # support. We ignore any unsupported extras here. valid_extras = self.extras.intersection(self.base.dist.iter_provided_extras()) invalid_extras = self.extras.difference(self.base.dist.iter_provided_extras()) for extra in sorted(invalid_extras): logger.warning( "%s %s does not provide the extra '%s'", self.base.name, self.version, extra, ) for r in self.base.dist.iter_dependencies(valid_extras): requirement = factory.make_requirement_from_spec( str(r), self.base._ireq, valid_extras ) if requirement: yield requirement def get_install_requirement(self) -> Optional[InstallRequirement]: # We don't return anything here, because we always # depend on the base candidate, and we'll get the # install requirement from that. return None class RequiresPythonCandidate(Candidate): is_installed = False source_link = None def __init__(self, py_version_info: Optional[Tuple[int, ...]]) -> None: if py_version_info is not None: version_info = normalize_version_info(py_version_info) else: version_info = sys.version_info[:3] self._version = Version(".".join(str(c) for c in version_info)) # We don't need to implement __eq__() and __ne__() since there is always # only one RequiresPythonCandidate in a resolution, i.e. the host Python. # The built-in object.__eq__() and object.__ne__() do exactly what we want. def __str__(self) -> str: return f"Python {self._version}" @property def project_name(self) -> NormalizedName: return REQUIRES_PYTHON_IDENTIFIER @property def name(self) -> str: return REQUIRES_PYTHON_IDENTIFIER @property def version(self) -> CandidateVersion: return self._version def format_for_error(self) -> str: return f"Python {self.version}" def iter_dependencies(self, with_requires: bool) -> Iterable[Optional[Requirement]]: return () def get_install_requirement(self) -> Optional[InstallRequirement]: return None