Created starter files for the project.
This commit is contained in:
commit
73f0c0db42
1992 changed files with 769897 additions and 0 deletions
26
venv/Lib/site-packages/pip/_vendor/resolvelib/__init__.py
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26
venv/Lib/site-packages/pip/_vendor/resolvelib/__init__.py
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__all__ = [
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"__version__",
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"AbstractProvider",
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"AbstractResolver",
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"BaseReporter",
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"InconsistentCandidate",
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"Resolver",
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"RequirementsConflicted",
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"ResolutionError",
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"ResolutionImpossible",
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"ResolutionTooDeep",
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]
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__version__ = "0.4.0"
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from .providers import AbstractProvider, AbstractResolver
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from .reporters import BaseReporter
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from .resolvers import (
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InconsistentCandidate,
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RequirementsConflicted,
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Resolver,
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ResolutionError,
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ResolutionImpossible,
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ResolutionTooDeep,
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)
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__all__ = ["Sequence"]
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try:
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from collections.abc import Sequence
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except ImportError:
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from collections import Sequence
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109
venv/Lib/site-packages/pip/_vendor/resolvelib/providers.py
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109
venv/Lib/site-packages/pip/_vendor/resolvelib/providers.py
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class AbstractProvider(object):
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"""Delegate class to provide requirement interface for the resolver.
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"""
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def identify(self, dependency):
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"""Given a dependency, return an identifier for it.
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This is used in many places to identify the dependency, e.g. whether
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two requirements should have their specifier parts merged, whether
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two specifications would conflict with each other (because they the
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same name but different versions).
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"""
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raise NotImplementedError
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def get_preference(self, resolution, candidates, information):
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"""Produce a sort key for given specification based on preference.
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The preference is defined as "I think this requirement should be
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resolved first". The lower the return value is, the more preferred
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this group of arguments is.
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:param resolution: Currently pinned candidate, or `None`.
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:param candidates: A list of possible candidates.
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:param information: A list of requirement information.
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Each information instance is a named tuple with two entries:
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* `requirement` specifies a requirement contributing to the current
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candidate list
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* `parent` specifies the candidate that provides (dependend on) the
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requirement, or `None` to indicate a root requirement.
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The preference could depend on a various of issues, including (not
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necessarily in this order):
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* Is this package pinned in the current resolution result?
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* How relaxed is the requirement? Stricter ones should probably be
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worked on first? (I don't know, actually.)
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* How many possibilities are there to satisfy this requirement? Those
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with few left should likely be worked on first, I guess?
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* Are there any known conflicts for this requirement? We should
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probably work on those with the most known conflicts.
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A sortable value should be returned (this will be used as the `key`
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parameter of the built-in sorting function). The smaller the value is,
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the more preferred this specification is (i.e. the sorting function
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is called with `reverse=False`).
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"""
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raise NotImplementedError
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def find_matches(self, requirements):
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"""Find all possible candidates that satisfy the given requirements.
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This should try to get candidates based on the requirements' types.
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For VCS, local, and archive requirements, the one-and-only match is
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returned, and for a "named" requirement, the index(es) should be
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consulted to find concrete candidates for this requirement.
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:param requirements: A collection of requirements which all of the the
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returned candidates must match. All requirements are guaranteed to
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have the same identifier. The collection is never empty.
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:returns: An iterable that orders candidates by preference, e.g. the
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most preferred candidate should come first.
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"""
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raise NotImplementedError
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def is_satisfied_by(self, requirement, candidate):
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"""Whether the given requirement can be satisfied by a candidate.
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The candidate is guarenteed to have been generated from the
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requirement.
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A boolean should be returned to indicate whether `candidate` is a
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viable solution to the requirement.
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"""
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raise NotImplementedError
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def get_dependencies(self, candidate):
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"""Get dependencies of a candidate.
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This should return a collection of requirements that `candidate`
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specifies as its dependencies.
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"""
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raise NotImplementedError
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class AbstractResolver(object):
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"""The thing that performs the actual resolution work.
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"""
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base_exception = Exception
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def __init__(self, provider, reporter):
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self.provider = provider
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self.reporter = reporter
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def resolve(self, requirements, **kwargs):
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"""Take a collection of constraints, spit out the resolution result.
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This returns a representation of the final resolution state, with one
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guarenteed attribute ``mapping`` that contains resolved candidates as
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values. The keys are their respective identifiers.
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:param requirements: A collection of constraints.
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:param kwargs: Additional keyword arguments that subclasses may accept.
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:raises: ``self.base_exception`` or its subclass.
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"""
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raise NotImplementedError
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42
venv/Lib/site-packages/pip/_vendor/resolvelib/reporters.py
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42
venv/Lib/site-packages/pip/_vendor/resolvelib/reporters.py
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class BaseReporter(object):
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"""Delegate class to provider progress reporting for the resolver.
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"""
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def starting(self):
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"""Called before the resolution actually starts.
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"""
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def starting_round(self, index):
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"""Called before each round of resolution starts.
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The index is zero-based.
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"""
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def ending_round(self, index, state):
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"""Called before each round of resolution ends.
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This is NOT called if the resolution ends at this round. Use `ending`
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if you want to report finalization. The index is zero-based.
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"""
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def ending(self, state):
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"""Called before the resolution ends successfully.
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"""
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def adding_requirement(self, requirement, parent):
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"""Called when adding a new requirement into the resolve criteria.
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:param requirement: The additional requirement to be applied to filter
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the available candidaites.
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:param parent: The candidate that requires ``requirement`` as a
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dependency, or None if ``requirement`` is one of the root
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requirements passed in from ``Resolver.resolve()``.
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"""
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def backtracking(self, candidate):
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"""Called when rejecting a candidate during backtracking.
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"""
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def pinning(self, candidate):
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"""Called when adding a candidate to the potential solution.
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"""
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428
venv/Lib/site-packages/pip/_vendor/resolvelib/resolvers.py
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428
venv/Lib/site-packages/pip/_vendor/resolvelib/resolvers.py
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import collections
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from .compat import collections_abc
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from .providers import AbstractResolver
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from .structs import DirectedGraph
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RequirementInformation = collections.namedtuple(
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"RequirementInformation", ["requirement", "parent"]
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)
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class ResolverException(Exception):
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"""A base class for all exceptions raised by this module.
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Exceptions derived by this class should all be handled in this module. Any
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bubbling pass the resolver should be treated as a bug.
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"""
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class RequirementsConflicted(ResolverException):
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def __init__(self, criterion):
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super(RequirementsConflicted, self).__init__(criterion)
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self.criterion = criterion
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def __str__(self):
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return "Requirements conflict: {}".format(
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", ".join(repr(r) for r in self.criterion.iter_requirement()),
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)
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class InconsistentCandidate(ResolverException):
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def __init__(self, candidate, criterion):
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super(InconsistentCandidate, self).__init__(candidate, criterion)
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self.candidate = candidate
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self.criterion = criterion
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def __str__(self):
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return "Provided candidate {!r} does not satisfy {}".format(
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self.candidate,
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", ".join(repr(r) for r in self.criterion.iter_requirement()),
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)
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class Criterion(object):
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"""Representation of possible resolution results of a package.
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This holds three attributes:
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* `information` is a collection of `RequirementInformation` pairs.
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Each pair is a requirement contributing to this criterion, and the
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candidate that provides the requirement.
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* `incompatibilities` is a collection of all known not-to-work candidates
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to exclude from consideration.
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* `candidates` is a collection containing all possible candidates deducted
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from the union of contributing requirements and known incompatibilities.
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It should never be empty, except when the criterion is an attribute of a
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raised `RequirementsConflicted` (in which case it is always empty).
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.. note::
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This class is intended to be externally immutable. **Do not** mutate
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any of its attribute containers.
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"""
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def __init__(self, candidates, information, incompatibilities):
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self.candidates = candidates
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self.information = information
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self.incompatibilities = incompatibilities
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def __repr__(self):
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requirements = ", ".join(
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"({!r}, via={!r})".format(req, parent)
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for req, parent in self.information
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)
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return "Criterion({})".format(requirements)
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@classmethod
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def from_requirement(cls, provider, requirement, parent):
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"""Build an instance from a requirement.
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"""
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candidates = provider.find_matches([requirement])
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if not isinstance(candidates, collections_abc.Sequence):
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candidates = list(candidates)
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criterion = cls(
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candidates=candidates,
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information=[RequirementInformation(requirement, parent)],
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incompatibilities=[],
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)
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if not candidates:
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raise RequirementsConflicted(criterion)
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return criterion
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def iter_requirement(self):
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return (i.requirement for i in self.information)
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def iter_parent(self):
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return (i.parent for i in self.information)
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def merged_with(self, provider, requirement, parent):
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"""Build a new instance from this and a new requirement.
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"""
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infos = list(self.information)
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infos.append(RequirementInformation(requirement, parent))
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candidates = provider.find_matches([r for r, _ in infos])
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if not isinstance(candidates, collections_abc.Sequence):
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candidates = list(candidates)
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criterion = type(self)(candidates, infos, list(self.incompatibilities))
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if not candidates:
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raise RequirementsConflicted(criterion)
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return criterion
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def excluded_of(self, candidate):
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"""Build a new instance from this, but excluding specified candidate.
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Returns the new instance, or None if we still have no valid candidates.
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"""
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incompats = list(self.incompatibilities)
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incompats.append(candidate)
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candidates = [c for c in self.candidates if c != candidate]
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if not candidates:
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return None
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criterion = type(self)(candidates, list(self.information), incompats)
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return criterion
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||||
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class ResolutionError(ResolverException):
|
||||
pass
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||||
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||||
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class ResolutionImpossible(ResolutionError):
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def __init__(self, causes):
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super(ResolutionImpossible, self).__init__(causes)
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# causes is a list of RequirementInformation objects
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self.causes = causes
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||||
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class ResolutionTooDeep(ResolutionError):
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def __init__(self, round_count):
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super(ResolutionTooDeep, self).__init__(round_count)
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self.round_count = round_count
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# Resolution state in a round.
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State = collections.namedtuple("State", "mapping criteria")
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class Resolution(object):
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"""Stateful resolution object.
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This is designed as a one-off object that holds information to kick start
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the resolution process, and holds the results afterwards.
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"""
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def __init__(self, provider, reporter):
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self._p = provider
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self._r = reporter
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||||
self._states = []
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@property
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def state(self):
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||||
try:
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||||
return self._states[-1]
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||||
except IndexError:
|
||||
raise AttributeError("state")
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||||
|
||||
def _push_new_state(self):
|
||||
"""Push a new state into history.
|
||||
|
||||
This new state will be used to hold resolution results of the next
|
||||
coming round.
|
||||
"""
|
||||
try:
|
||||
base = self._states[-1]
|
||||
except IndexError:
|
||||
state = State(mapping=collections.OrderedDict(), criteria={})
|
||||
else:
|
||||
state = State(
|
||||
mapping=base.mapping.copy(), criteria=base.criteria.copy(),
|
||||
)
|
||||
self._states.append(state)
|
||||
|
||||
def _merge_into_criterion(self, requirement, parent):
|
||||
self._r.adding_requirement(requirement, parent)
|
||||
name = self._p.identify(requirement)
|
||||
try:
|
||||
crit = self.state.criteria[name]
|
||||
except KeyError:
|
||||
crit = Criterion.from_requirement(self._p, requirement, parent)
|
||||
else:
|
||||
crit = crit.merged_with(self._p, requirement, parent)
|
||||
return name, crit
|
||||
|
||||
def _get_criterion_item_preference(self, item):
|
||||
name, criterion = item
|
||||
try:
|
||||
pinned = self.state.mapping[name]
|
||||
except KeyError:
|
||||
pinned = None
|
||||
return self._p.get_preference(
|
||||
pinned, criterion.candidates, criterion.information,
|
||||
)
|
||||
|
||||
def _is_current_pin_satisfying(self, name, criterion):
|
||||
try:
|
||||
current_pin = self.state.mapping[name]
|
||||
except KeyError:
|
||||
return False
|
||||
return all(
|
||||
self._p.is_satisfied_by(r, current_pin)
|
||||
for r in criterion.iter_requirement()
|
||||
)
|
||||
|
||||
def _get_criteria_to_update(self, candidate):
|
||||
criteria = {}
|
||||
for r in self._p.get_dependencies(candidate):
|
||||
name, crit = self._merge_into_criterion(r, parent=candidate)
|
||||
criteria[name] = crit
|
||||
return criteria
|
||||
|
||||
def _attempt_to_pin_criterion(self, name, criterion):
|
||||
causes = []
|
||||
for candidate in criterion.candidates:
|
||||
try:
|
||||
criteria = self._get_criteria_to_update(candidate)
|
||||
except RequirementsConflicted as e:
|
||||
causes.append(e.criterion)
|
||||
continue
|
||||
|
||||
# Check the newly-pinned candidate actually works. This should
|
||||
# always pass under normal circumstances, but in the case of a
|
||||
# faulty provider, we will raise an error to notify the implementer
|
||||
# to fix find_matches() and/or is_satisfied_by().
|
||||
satisfied = all(
|
||||
self._p.is_satisfied_by(r, candidate)
|
||||
for r in criterion.iter_requirement()
|
||||
)
|
||||
if not satisfied:
|
||||
raise InconsistentCandidate(candidate, criterion)
|
||||
|
||||
# Put newly-pinned candidate at the end. This is essential because
|
||||
# backtracking looks at this mapping to get the last pin.
|
||||
self._r.pinning(candidate)
|
||||
self.state.mapping.pop(name, None)
|
||||
self.state.mapping[name] = candidate
|
||||
self.state.criteria.update(criteria)
|
||||
|
||||
return []
|
||||
|
||||
# All candidates tried, nothing works. This criterion is a dead
|
||||
# end, signal for backtracking.
|
||||
return causes
|
||||
|
||||
def _backtrack(self):
|
||||
# Drop the current state, it's known not to work.
|
||||
del self._states[-1]
|
||||
|
||||
# We need at least 2 states here:
|
||||
# (a) One to backtrack to.
|
||||
# (b) One to restore state (a) to its state prior to candidate-pinning,
|
||||
# so we can pin another one instead.
|
||||
|
||||
while len(self._states) >= 2:
|
||||
# Retract the last candidate pin.
|
||||
prev_state = self._states.pop()
|
||||
try:
|
||||
name, candidate = prev_state.mapping.popitem()
|
||||
except KeyError:
|
||||
continue
|
||||
self._r.backtracking(candidate)
|
||||
|
||||
# Create a new state to work on, with the newly known not-working
|
||||
# candidate excluded.
|
||||
self._push_new_state()
|
||||
|
||||
# Mark the retracted candidate as incompatible.
|
||||
criterion = self.state.criteria[name].excluded_of(candidate)
|
||||
if criterion is None:
|
||||
# This state still does not work. Try the still previous state.
|
||||
del self._states[-1]
|
||||
continue
|
||||
self.state.criteria[name] = criterion
|
||||
|
||||
return True
|
||||
|
||||
return False
|
||||
|
||||
def resolve(self, requirements, max_rounds):
|
||||
if self._states:
|
||||
raise RuntimeError("already resolved")
|
||||
|
||||
self._push_new_state()
|
||||
for r in requirements:
|
||||
try:
|
||||
name, crit = self._merge_into_criterion(r, parent=None)
|
||||
except RequirementsConflicted as e:
|
||||
raise ResolutionImpossible(e.criterion.information)
|
||||
self.state.criteria[name] = crit
|
||||
|
||||
self._r.starting()
|
||||
|
||||
for round_index in range(max_rounds):
|
||||
self._r.starting_round(round_index)
|
||||
|
||||
self._push_new_state()
|
||||
curr = self.state
|
||||
|
||||
unsatisfied_criterion_items = [
|
||||
item
|
||||
for item in self.state.criteria.items()
|
||||
if not self._is_current_pin_satisfying(*item)
|
||||
]
|
||||
|
||||
# All criteria are accounted for. Nothing more to pin, we are done!
|
||||
if not unsatisfied_criterion_items:
|
||||
del self._states[-1]
|
||||
self._r.ending(curr)
|
||||
return self.state
|
||||
|
||||
# Choose the most preferred unpinned criterion to try.
|
||||
name, criterion = min(
|
||||
unsatisfied_criterion_items,
|
||||
key=self._get_criterion_item_preference,
|
||||
)
|
||||
failure_causes = self._attempt_to_pin_criterion(name, criterion)
|
||||
|
||||
# Backtrack if pinning fails.
|
||||
if failure_causes:
|
||||
result = self._backtrack()
|
||||
if not result:
|
||||
causes = [
|
||||
i for crit in failure_causes for i in crit.information
|
||||
]
|
||||
raise ResolutionImpossible(causes)
|
||||
|
||||
self._r.ending_round(round_index, curr)
|
||||
|
||||
raise ResolutionTooDeep(max_rounds)
|
||||
|
||||
|
||||
def _has_route_to_root(criteria, key, all_keys, connected):
|
||||
if key in connected:
|
||||
return True
|
||||
if key not in criteria:
|
||||
return False
|
||||
for p in criteria[key].iter_parent():
|
||||
try:
|
||||
pkey = all_keys[id(p)]
|
||||
except KeyError:
|
||||
continue
|
||||
if pkey in connected:
|
||||
connected.add(key)
|
||||
return True
|
||||
if _has_route_to_root(criteria, pkey, all_keys, connected):
|
||||
connected.add(key)
|
||||
return True
|
||||
return False
|
||||
|
||||
|
||||
Result = collections.namedtuple("Result", "mapping graph criteria")
|
||||
|
||||
|
||||
def _build_result(state):
|
||||
mapping = state.mapping
|
||||
all_keys = {id(v): k for k, v in mapping.items()}
|
||||
all_keys[id(None)] = None
|
||||
|
||||
graph = DirectedGraph()
|
||||
graph.add(None) # Sentinel as root dependencies' parent.
|
||||
|
||||
connected = {None}
|
||||
for key, criterion in state.criteria.items():
|
||||
if not _has_route_to_root(state.criteria, key, all_keys, connected):
|
||||
continue
|
||||
if key not in graph:
|
||||
graph.add(key)
|
||||
for p in criterion.iter_parent():
|
||||
try:
|
||||
pkey = all_keys[id(p)]
|
||||
except KeyError:
|
||||
continue
|
||||
if pkey not in graph:
|
||||
graph.add(pkey)
|
||||
graph.connect(pkey, key)
|
||||
|
||||
return Result(
|
||||
mapping={k: v for k, v in mapping.items() if k in connected},
|
||||
graph=graph,
|
||||
criteria=state.criteria,
|
||||
)
|
||||
|
||||
|
||||
class Resolver(AbstractResolver):
|
||||
"""The thing that performs the actual resolution work.
|
||||
"""
|
||||
|
||||
base_exception = ResolverException
|
||||
|
||||
def resolve(self, requirements, max_rounds=100):
|
||||
"""Take a collection of constraints, spit out the resolution result.
|
||||
|
||||
The return value is a representation to the final resolution result. It
|
||||
is a tuple subclass with three public members:
|
||||
|
||||
* `mapping`: A dict of resolved candidates. Each key is an identifier
|
||||
of a requirement (as returned by the provider's `identify` method),
|
||||
and the value is the resolved candidate.
|
||||
* `graph`: A `DirectedGraph` instance representing the dependency tree.
|
||||
The vertices are keys of `mapping`, and each edge represents *why*
|
||||
a particular package is included. A special vertex `None` is
|
||||
included to represent parents of user-supplied requirements.
|
||||
* `criteria`: A dict of "criteria" that hold detailed information on
|
||||
how edges in the graph are derived. Each key is an identifier of a
|
||||
requirement, and the value is a `Criterion` instance.
|
||||
|
||||
The following exceptions may be raised if a resolution cannot be found:
|
||||
|
||||
* `ResolutionImpossible`: A resolution cannot be found for the given
|
||||
combination of requirements. The `causes` attribute of the
|
||||
exception is a list of (requirement, parent), giving the
|
||||
requirements that could not be satisfied.
|
||||
* `ResolutionTooDeep`: The dependency tree is too deeply nested and
|
||||
the resolver gave up. This is usually caused by a circular
|
||||
dependency, but you can try to resolve this by increasing the
|
||||
`max_rounds` argument.
|
||||
"""
|
||||
resolution = Resolution(self.provider, self.reporter)
|
||||
state = resolution.resolve(requirements, max_rounds=max_rounds)
|
||||
return _build_result(state)
|
||||
68
venv/Lib/site-packages/pip/_vendor/resolvelib/structs.py
Normal file
68
venv/Lib/site-packages/pip/_vendor/resolvelib/structs.py
Normal file
|
|
@ -0,0 +1,68 @@
|
|||
class DirectedGraph(object):
|
||||
"""A graph structure with directed edges.
|
||||
"""
|
||||
|
||||
def __init__(self):
|
||||
self._vertices = set()
|
||||
self._forwards = {} # <key> -> Set[<key>]
|
||||
self._backwards = {} # <key> -> Set[<key>]
|
||||
|
||||
def __iter__(self):
|
||||
return iter(self._vertices)
|
||||
|
||||
def __len__(self):
|
||||
return len(self._vertices)
|
||||
|
||||
def __contains__(self, key):
|
||||
return key in self._vertices
|
||||
|
||||
def copy(self):
|
||||
"""Return a shallow copy of this graph.
|
||||
"""
|
||||
other = DirectedGraph()
|
||||
other._vertices = set(self._vertices)
|
||||
other._forwards = {k: set(v) for k, v in self._forwards.items()}
|
||||
other._backwards = {k: set(v) for k, v in self._backwards.items()}
|
||||
return other
|
||||
|
||||
def add(self, key):
|
||||
"""Add a new vertex to the graph.
|
||||
"""
|
||||
if key in self._vertices:
|
||||
raise ValueError("vertex exists")
|
||||
self._vertices.add(key)
|
||||
self._forwards[key] = set()
|
||||
self._backwards[key] = set()
|
||||
|
||||
def remove(self, key):
|
||||
"""Remove a vertex from the graph, disconnecting all edges from/to it.
|
||||
"""
|
||||
self._vertices.remove(key)
|
||||
for f in self._forwards.pop(key):
|
||||
self._backwards[f].remove(key)
|
||||
for t in self._backwards.pop(key):
|
||||
self._forwards[t].remove(key)
|
||||
|
||||
def connected(self, f, t):
|
||||
return f in self._backwards[t] and t in self._forwards[f]
|
||||
|
||||
def connect(self, f, t):
|
||||
"""Connect two existing vertices.
|
||||
|
||||
Nothing happens if the vertices are already connected.
|
||||
"""
|
||||
if t not in self._vertices:
|
||||
raise KeyError(t)
|
||||
self._forwards[f].add(t)
|
||||
self._backwards[t].add(f)
|
||||
|
||||
def iter_edges(self):
|
||||
for f, children in self._forwards.items():
|
||||
for t in children:
|
||||
yield f, t
|
||||
|
||||
def iter_children(self, key):
|
||||
return iter(self._forwards[key])
|
||||
|
||||
def iter_parents(self, key):
|
||||
return iter(self._backwards[key])
|
||||
Loading…
Add table
Add a link
Reference in a new issue