diff options
Diffstat (limited to 'third_party/python/pip/pip/_internal/resolution/resolvelib/factory.py')
| -rw-r--r-- | third_party/python/pip/pip/_internal/resolution/resolvelib/factory.py | 731 |
1 files changed, 731 insertions, 0 deletions
diff --git a/third_party/python/pip/pip/_internal/resolution/resolvelib/factory.py b/third_party/python/pip/pip/_internal/resolution/resolvelib/factory.py new file mode 100644 index 0000000000..a4c24b52a1 --- /dev/null +++ b/third_party/python/pip/pip/_internal/resolution/resolvelib/factory.py @@ -0,0 +1,731 @@ +import contextlib +import functools +import logging +from typing import ( + TYPE_CHECKING, + Dict, + FrozenSet, + Iterable, + Iterator, + List, + Mapping, + NamedTuple, + Optional, + Sequence, + Set, + Tuple, + TypeVar, + cast, +) + +from pip._vendor.packaging.requirements import InvalidRequirement +from pip._vendor.packaging.specifiers import SpecifierSet +from pip._vendor.packaging.utils import NormalizedName, canonicalize_name +from pip._vendor.resolvelib import ResolutionImpossible + +from pip._internal.cache import CacheEntry, WheelCache +from pip._internal.exceptions import ( + DistributionNotFound, + InstallationError, + MetadataInconsistent, + UnsupportedPythonVersion, + UnsupportedWheel, +) +from pip._internal.index.package_finder import PackageFinder +from pip._internal.metadata import BaseDistribution, get_default_environment +from pip._internal.models.link import Link +from pip._internal.models.wheel import Wheel +from pip._internal.operations.prepare import RequirementPreparer +from pip._internal.req.constructors import install_req_from_link_and_ireq +from pip._internal.req.req_install import ( + InstallRequirement, + check_invalid_constraint_type, +) +from pip._internal.resolution.base import InstallRequirementProvider +from pip._internal.utils.compatibility_tags import get_supported +from pip._internal.utils.hashes import Hashes +from pip._internal.utils.packaging import get_requirement +from pip._internal.utils.virtualenv import running_under_virtualenv + +from .base import Candidate, CandidateVersion, Constraint, Requirement +from .candidates import ( + AlreadyInstalledCandidate, + BaseCandidate, + EditableCandidate, + ExtrasCandidate, + LinkCandidate, + RequiresPythonCandidate, + as_base_candidate, +) +from .found_candidates import FoundCandidates, IndexCandidateInfo +from .requirements import ( + ExplicitRequirement, + RequiresPythonRequirement, + SpecifierRequirement, + UnsatisfiableRequirement, +) + +if TYPE_CHECKING: + from typing import Protocol + + class ConflictCause(Protocol): + requirement: RequiresPythonRequirement + parent: Candidate + + +logger = logging.getLogger(__name__) + +C = TypeVar("C") +Cache = Dict[Link, C] + + +class CollectedRootRequirements(NamedTuple): + requirements: List[Requirement] + constraints: Dict[str, Constraint] + user_requested: Dict[str, int] + + +class Factory: + def __init__( + self, + finder: PackageFinder, + preparer: RequirementPreparer, + make_install_req: InstallRequirementProvider, + wheel_cache: Optional[WheelCache], + use_user_site: bool, + force_reinstall: bool, + ignore_installed: bool, + ignore_requires_python: bool, + py_version_info: Optional[Tuple[int, ...]] = None, + ) -> None: + self._finder = finder + self.preparer = preparer + self._wheel_cache = wheel_cache + self._python_candidate = RequiresPythonCandidate(py_version_info) + self._make_install_req_from_spec = make_install_req + self._use_user_site = use_user_site + self._force_reinstall = force_reinstall + self._ignore_requires_python = ignore_requires_python + + self._build_failures: Cache[InstallationError] = {} + self._link_candidate_cache: Cache[LinkCandidate] = {} + self._editable_candidate_cache: Cache[EditableCandidate] = {} + self._installed_candidate_cache: Dict[str, AlreadyInstalledCandidate] = {} + self._extras_candidate_cache: Dict[ + Tuple[int, FrozenSet[str]], ExtrasCandidate + ] = {} + + if not ignore_installed: + env = get_default_environment() + self._installed_dists = { + dist.canonical_name: dist + for dist in env.iter_installed_distributions(local_only=False) + } + else: + self._installed_dists = {} + + @property + def force_reinstall(self) -> bool: + return self._force_reinstall + + def _fail_if_link_is_unsupported_wheel(self, link: Link) -> None: + if not link.is_wheel: + return + wheel = Wheel(link.filename) + if wheel.supported(self._finder.target_python.get_tags()): + return + msg = f"{link.filename} is not a supported wheel on this platform." + raise UnsupportedWheel(msg) + + def _make_extras_candidate( + self, base: BaseCandidate, extras: FrozenSet[str] + ) -> ExtrasCandidate: + cache_key = (id(base), extras) + try: + candidate = self._extras_candidate_cache[cache_key] + except KeyError: + candidate = ExtrasCandidate(base, extras) + self._extras_candidate_cache[cache_key] = candidate + return candidate + + def _make_candidate_from_dist( + self, + dist: BaseDistribution, + extras: FrozenSet[str], + template: InstallRequirement, + ) -> Candidate: + try: + base = self._installed_candidate_cache[dist.canonical_name] + except KeyError: + base = AlreadyInstalledCandidate(dist, template, factory=self) + self._installed_candidate_cache[dist.canonical_name] = base + if not extras: + return base + return self._make_extras_candidate(base, extras) + + def _make_candidate_from_link( + self, + link: Link, + extras: FrozenSet[str], + template: InstallRequirement, + name: Optional[NormalizedName], + version: Optional[CandidateVersion], + ) -> Optional[Candidate]: + # TODO: Check already installed candidate, and use it if the link and + # editable flag match. + + if link in self._build_failures: + # We already tried this candidate before, and it does not build. + # Don't bother trying again. + return None + + if template.editable: + if link not in self._editable_candidate_cache: + try: + self._editable_candidate_cache[link] = EditableCandidate( + link, + template, + factory=self, + name=name, + version=version, + ) + except MetadataInconsistent as e: + logger.info( + "Discarding [blue underline]%s[/]: [yellow]%s[reset]", + link, + e, + extra={"markup": True}, + ) + self._build_failures[link] = e + return None + + base: BaseCandidate = self._editable_candidate_cache[link] + else: + if link not in self._link_candidate_cache: + try: + self._link_candidate_cache[link] = LinkCandidate( + link, + template, + factory=self, + name=name, + version=version, + ) + except MetadataInconsistent as e: + logger.info( + "Discarding [blue underline]%s[/]: [yellow]%s[reset]", + link, + e, + extra={"markup": True}, + ) + self._build_failures[link] = e + return None + base = self._link_candidate_cache[link] + + if not extras: + return base + return self._make_extras_candidate(base, extras) + + def _iter_found_candidates( + self, + ireqs: Sequence[InstallRequirement], + specifier: SpecifierSet, + hashes: Hashes, + prefers_installed: bool, + incompatible_ids: Set[int], + ) -> Iterable[Candidate]: + if not ireqs: + return () + + # The InstallRequirement implementation requires us to give it a + # "template". Here we just choose the first requirement to represent + # all of them. + # Hopefully the Project model can correct this mismatch in the future. + template = ireqs[0] + assert template.req, "Candidates found on index must be PEP 508" + name = canonicalize_name(template.req.name) + + extras: FrozenSet[str] = frozenset() + for ireq in ireqs: + assert ireq.req, "Candidates found on index must be PEP 508" + specifier &= ireq.req.specifier + hashes &= ireq.hashes(trust_internet=False) + extras |= frozenset(ireq.extras) + + def _get_installed_candidate() -> Optional[Candidate]: + """Get the candidate for the currently-installed version.""" + # If --force-reinstall is set, we want the version from the index + # instead, so we "pretend" there is nothing installed. + if self._force_reinstall: + return None + try: + installed_dist = self._installed_dists[name] + except KeyError: + return None + # Don't use the installed distribution if its version does not fit + # the current dependency graph. + if not specifier.contains(installed_dist.version, prereleases=True): + return None + candidate = self._make_candidate_from_dist( + dist=installed_dist, + extras=extras, + template=template, + ) + # The candidate is a known incompatibility. Don't use it. + if id(candidate) in incompatible_ids: + return None + return candidate + + def iter_index_candidate_infos() -> Iterator[IndexCandidateInfo]: + result = self._finder.find_best_candidate( + project_name=name, + specifier=specifier, + hashes=hashes, + ) + icans = list(result.iter_applicable()) + + # PEP 592: Yanked releases are ignored unless the specifier + # explicitly pins a version (via '==' or '===') that can be + # solely satisfied by a yanked release. + all_yanked = all(ican.link.is_yanked for ican in icans) + + def is_pinned(specifier: SpecifierSet) -> bool: + for sp in specifier: + if sp.operator == "===": + return True + if sp.operator != "==": + continue + if sp.version.endswith(".*"): + continue + return True + return False + + pinned = is_pinned(specifier) + + # PackageFinder returns earlier versions first, so we reverse. + for ican in reversed(icans): + if not (all_yanked and pinned) and ican.link.is_yanked: + continue + func = functools.partial( + self._make_candidate_from_link, + link=ican.link, + extras=extras, + template=template, + name=name, + version=ican.version, + ) + yield ican.version, func + + return FoundCandidates( + iter_index_candidate_infos, + _get_installed_candidate(), + prefers_installed, + incompatible_ids, + ) + + def _iter_explicit_candidates_from_base( + self, + base_requirements: Iterable[Requirement], + extras: FrozenSet[str], + ) -> Iterator[Candidate]: + """Produce explicit candidates from the base given an extra-ed package. + + :param base_requirements: Requirements known to the resolver. The + requirements are guaranteed to not have extras. + :param extras: The extras to inject into the explicit requirements' + candidates. + """ + for req in base_requirements: + lookup_cand, _ = req.get_candidate_lookup() + if lookup_cand is None: # Not explicit. + continue + # We've stripped extras from the identifier, and should always + # get a BaseCandidate here, unless there's a bug elsewhere. + base_cand = as_base_candidate(lookup_cand) + assert base_cand is not None, "no extras here" + yield self._make_extras_candidate(base_cand, extras) + + def _iter_candidates_from_constraints( + self, + identifier: str, + constraint: Constraint, + template: InstallRequirement, + ) -> Iterator[Candidate]: + """Produce explicit candidates from constraints. + + This creates "fake" InstallRequirement objects that are basically clones + of what "should" be the template, but with original_link set to link. + """ + for link in constraint.links: + self._fail_if_link_is_unsupported_wheel(link) + candidate = self._make_candidate_from_link( + link, + extras=frozenset(), + template=install_req_from_link_and_ireq(link, template), + name=canonicalize_name(identifier), + version=None, + ) + if candidate: + yield candidate + + def find_candidates( + self, + identifier: str, + requirements: Mapping[str, Iterable[Requirement]], + incompatibilities: Mapping[str, Iterator[Candidate]], + constraint: Constraint, + prefers_installed: bool, + ) -> Iterable[Candidate]: + # Collect basic lookup information from the requirements. + explicit_candidates: Set[Candidate] = set() + ireqs: List[InstallRequirement] = [] + for req in requirements[identifier]: + cand, ireq = req.get_candidate_lookup() + if cand is not None: + explicit_candidates.add(cand) + if ireq is not None: + ireqs.append(ireq) + + # If the current identifier contains extras, add explicit candidates + # from entries from extra-less identifier. + with contextlib.suppress(InvalidRequirement): + parsed_requirement = get_requirement(identifier) + explicit_candidates.update( + self._iter_explicit_candidates_from_base( + requirements.get(parsed_requirement.name, ()), + frozenset(parsed_requirement.extras), + ), + ) + + # Add explicit candidates from constraints. We only do this if there are + # known ireqs, which represent requirements not already explicit. If + # there are no ireqs, we're constraining already-explicit requirements, + # which is handled later when we return the explicit candidates. + if ireqs: + try: + explicit_candidates.update( + self._iter_candidates_from_constraints( + identifier, + constraint, + template=ireqs[0], + ), + ) + except UnsupportedWheel: + # If we're constrained to install a wheel incompatible with the + # target architecture, no candidates will ever be valid. + return () + + # Since we cache all the candidates, incompatibility identification + # can be made quicker by comparing only the id() values. + incompat_ids = {id(c) for c in incompatibilities.get(identifier, ())} + + # If none of the requirements want an explicit candidate, we can ask + # the finder for candidates. + if not explicit_candidates: + return self._iter_found_candidates( + ireqs, + constraint.specifier, + constraint.hashes, + prefers_installed, + incompat_ids, + ) + + return ( + c + for c in explicit_candidates + if id(c) not in incompat_ids + and constraint.is_satisfied_by(c) + and all(req.is_satisfied_by(c) for req in requirements[identifier]) + ) + + def _make_requirement_from_install_req( + self, ireq: InstallRequirement, requested_extras: Iterable[str] + ) -> Optional[Requirement]: + if not ireq.match_markers(requested_extras): + logger.info( + "Ignoring %s: markers '%s' don't match your environment", + ireq.name, + ireq.markers, + ) + return None + if not ireq.link: + return SpecifierRequirement(ireq) + self._fail_if_link_is_unsupported_wheel(ireq.link) + cand = self._make_candidate_from_link( + ireq.link, + extras=frozenset(ireq.extras), + template=ireq, + name=canonicalize_name(ireq.name) if ireq.name else None, + version=None, + ) + if cand is None: + # There's no way we can satisfy a URL requirement if the underlying + # candidate fails to build. An unnamed URL must be user-supplied, so + # we fail eagerly. If the URL is named, an unsatisfiable requirement + # can make the resolver do the right thing, either backtrack (and + # maybe find some other requirement that's buildable) or raise a + # ResolutionImpossible eventually. + if not ireq.name: + raise self._build_failures[ireq.link] + return UnsatisfiableRequirement(canonicalize_name(ireq.name)) + return self.make_requirement_from_candidate(cand) + + def collect_root_requirements( + self, root_ireqs: List[InstallRequirement] + ) -> CollectedRootRequirements: + collected = CollectedRootRequirements([], {}, {}) + for i, ireq in enumerate(root_ireqs): + if ireq.constraint: + # Ensure we only accept valid constraints + problem = check_invalid_constraint_type(ireq) + if problem: + raise InstallationError(problem) + if not ireq.match_markers(): + continue + assert ireq.name, "Constraint must be named" + name = canonicalize_name(ireq.name) + if name in collected.constraints: + collected.constraints[name] &= ireq + else: + collected.constraints[name] = Constraint.from_ireq(ireq) + else: + req = self._make_requirement_from_install_req( + ireq, + requested_extras=(), + ) + if req is None: + continue + if ireq.user_supplied and req.name not in collected.user_requested: + collected.user_requested[req.name] = i + collected.requirements.append(req) + return collected + + def make_requirement_from_candidate( + self, candidate: Candidate + ) -> ExplicitRequirement: + return ExplicitRequirement(candidate) + + def make_requirement_from_spec( + self, + specifier: str, + comes_from: Optional[InstallRequirement], + requested_extras: Iterable[str] = (), + ) -> Optional[Requirement]: + ireq = self._make_install_req_from_spec(specifier, comes_from) + return self._make_requirement_from_install_req(ireq, requested_extras) + + def make_requires_python_requirement( + self, + specifier: SpecifierSet, + ) -> Optional[Requirement]: + if self._ignore_requires_python: + return None + # Don't bother creating a dependency for an empty Requires-Python. + if not str(specifier): + return None + return RequiresPythonRequirement(specifier, self._python_candidate) + + def get_wheel_cache_entry( + self, link: Link, name: Optional[str] + ) -> Optional[CacheEntry]: + """Look up the link in the wheel cache. + + If ``preparer.require_hashes`` is True, don't use the wheel cache, + because cached wheels, always built locally, have different hashes + than the files downloaded from the index server and thus throw false + hash mismatches. Furthermore, cached wheels at present have + nondeterministic contents due to file modification times. + """ + if self._wheel_cache is None or self.preparer.require_hashes: + return None + return self._wheel_cache.get_cache_entry( + link=link, + package_name=name, + supported_tags=get_supported(), + ) + + def get_dist_to_uninstall(self, candidate: Candidate) -> Optional[BaseDistribution]: + # TODO: Are there more cases this needs to return True? Editable? + dist = self._installed_dists.get(candidate.project_name) + if dist is None: # Not installed, no uninstallation required. + return None + + # We're installing into global site. The current installation must + # be uninstalled, no matter it's in global or user site, because the + # user site installation has precedence over global. + if not self._use_user_site: + return dist + + # We're installing into user site. Remove the user site installation. + if dist.in_usersite: + return dist + + # We're installing into user site, but the installed incompatible + # package is in global site. We can't uninstall that, and would let + # the new user installation to "shadow" it. But shadowing won't work + # in virtual environments, so we error out. + if running_under_virtualenv() and dist.in_site_packages: + message = ( + f"Will not install to the user site because it will lack " + f"sys.path precedence to {dist.raw_name} in {dist.location}" + ) + raise InstallationError(message) + return None + + def _report_requires_python_error( + self, causes: Sequence["ConflictCause"] + ) -> UnsupportedPythonVersion: + assert causes, "Requires-Python error reported with no cause" + + version = self._python_candidate.version + + if len(causes) == 1: + specifier = str(causes[0].requirement.specifier) + message = ( + f"Package {causes[0].parent.name!r} requires a different " + f"Python: {version} not in {specifier!r}" + ) + return UnsupportedPythonVersion(message) + + message = f"Packages require a different Python. {version} not in:" + for cause in causes: + package = cause.parent.format_for_error() + specifier = str(cause.requirement.specifier) + message += f"\n{specifier!r} (required by {package})" + return UnsupportedPythonVersion(message) + + def _report_single_requirement_conflict( + self, req: Requirement, parent: Optional[Candidate] + ) -> DistributionNotFound: + if parent is None: + req_disp = str(req) + else: + req_disp = f"{req} (from {parent.name})" + + cands = self._finder.find_all_candidates(req.project_name) + skipped_by_requires_python = self._finder.requires_python_skipped_reasons() + versions = [str(v) for v in sorted({c.version for c in cands})] + + if skipped_by_requires_python: + logger.critical( + "Ignored the following versions that require a different python " + "version: %s", + "; ".join(skipped_by_requires_python) or "none", + ) + logger.critical( + "Could not find a version that satisfies the requirement %s " + "(from versions: %s)", + req_disp, + ", ".join(versions) or "none", + ) + if str(req) == "requirements.txt": + logger.info( + "HINT: You are attempting to install a package literally " + 'named "requirements.txt" (which cannot exist). Consider ' + "using the '-r' flag to install the packages listed in " + "requirements.txt" + ) + + return DistributionNotFound(f"No matching distribution found for {req}") + + def get_installation_error( + self, + e: "ResolutionImpossible[Requirement, Candidate]", + constraints: Dict[str, Constraint], + ) -> InstallationError: + + assert e.causes, "Installation error reported with no cause" + + # If one of the things we can't solve is "we need Python X.Y", + # that is what we report. + requires_python_causes = [ + cause + for cause in e.causes + if isinstance(cause.requirement, RequiresPythonRequirement) + and not cause.requirement.is_satisfied_by(self._python_candidate) + ] + if requires_python_causes: + # The comprehension above makes sure all Requirement instances are + # RequiresPythonRequirement, so let's cast for convenience. + return self._report_requires_python_error( + cast("Sequence[ConflictCause]", requires_python_causes), + ) + + # Otherwise, we have a set of causes which can't all be satisfied + # at once. + + # The simplest case is when we have *one* cause that can't be + # satisfied. We just report that case. + if len(e.causes) == 1: + req, parent = e.causes[0] + if req.name not in constraints: + return self._report_single_requirement_conflict(req, parent) + + # OK, we now have a list of requirements that can't all be + # satisfied at once. + + # A couple of formatting helpers + def text_join(parts: List[str]) -> str: + if len(parts) == 1: + return parts[0] + + return ", ".join(parts[:-1]) + " and " + parts[-1] + + def describe_trigger(parent: Candidate) -> str: + ireq = parent.get_install_requirement() + if not ireq or not ireq.comes_from: + return f"{parent.name}=={parent.version}" + if isinstance(ireq.comes_from, InstallRequirement): + return str(ireq.comes_from.name) + return str(ireq.comes_from) + + triggers = set() + for req, parent in e.causes: + if parent is None: + # This is a root requirement, so we can report it directly + trigger = req.format_for_error() + else: + trigger = describe_trigger(parent) + triggers.add(trigger) + + if triggers: + info = text_join(sorted(triggers)) + else: + info = "the requested packages" + + msg = ( + "Cannot install {} because these package versions " + "have conflicting dependencies.".format(info) + ) + logger.critical(msg) + msg = "\nThe conflict is caused by:" + + relevant_constraints = set() + for req, parent in e.causes: + if req.name in constraints: + relevant_constraints.add(req.name) + msg = msg + "\n " + if parent: + msg = msg + f"{parent.name} {parent.version} depends on " + else: + msg = msg + "The user requested " + msg = msg + req.format_for_error() + for key in relevant_constraints: + spec = constraints[key].specifier + msg += f"\n The user requested (constraint) {key}{spec}" + + msg = ( + msg + + "\n\n" + + "To fix this you could try to:\n" + + "1. loosen the range of package versions you've specified\n" + + "2. remove package versions to allow pip attempt to solve " + + "the dependency conflict\n" + ) + + logger.info(msg) + + return DistributionNotFound( + "ResolutionImpossible: for help visit " + "https://pip.pypa.io/en/latest/topics/dependency-resolution/" + "#dealing-with-dependency-conflicts" + ) |