Edit File: providers.cpython-37.pyc
B �j�c� � @ s$ G d d� de �ZG dd� de �ZdS )c @ s8 e Zd ZdZdd� Zdd� Zdd� Zdd � Zd d � Zd S ) �AbstractProviderzFDelegate class to provide requirement interface for the resolver. c C s t �dS )aI Given a dependency, return an identifier for it. This is used in many places to identify the dependency, e.g. whether two requirements should have their specifier parts merged, whether two specifications would conflict with each other (because they the same name but different versions). N)�NotImplementedError)�self� dependency� r ��/builddir/build/BUILDROOT/alt-python37-pip-20.2.4-5.el8.x86_64/opt/alt/python37/lib/python3.7/site-packages/pip/_vendor/resolvelib/providers.py�identify s zAbstractProvider.identifyc C s t �dS )aT Produce a sort key for given specification based on preference. The preference is defined as "I think this requirement should be resolved first". The lower the return value is, the more preferred this group of arguments is. :param resolution: Currently pinned candidate, or `None`. :param candidates: A list of possible candidates. :param information: A list of requirement information. Each information instance is a named tuple with two entries: * `requirement` specifies a requirement contributing to the current candidate list * `parent` specifies the candidate that provides (dependend on) the requirement, or `None` to indicate a root requirement. The preference could depend on a various of issues, including (not necessarily in this order): * Is this package pinned in the current resolution result? * How relaxed is the requirement? Stricter ones should probably be worked on first? (I don't know, actually.) * How many possibilities are there to satisfy this requirement? Those with few left should likely be worked on first, I guess? * Are there any known conflicts for this requirement? We should probably work on those with the most known conflicts. A sortable value should be returned (this will be used as the `key` parameter of the built-in sorting function). The smaller the value is, the more preferred this specification is (i.e. the sorting function is called with `reverse=False`). N)r )r � resolution� candidatesZ informationr r r �get_preference s "z AbstractProvider.get_preferencec C s t �dS )a� Find all possible candidates that satisfy the given requirements. This should try to get candidates based on the requirements' types. For VCS, local, and archive requirements, the one-and-only match is returned, and for a "named" requirement, the index(es) should be consulted to find concrete candidates for this requirement. :param requirements: A collection of requirements which all of the the returned candidates must match. All requirements are guaranteed to have the same identifier. The collection is never empty. :returns: An iterable that orders candidates by preference, e.g. the most preferred candidate should come first. N)r )r � requirementsr r r � find_matches3 s z AbstractProvider.find_matchesc C s t �dS )a Whether the given requirement can be satisfied by a candidate. The candidate is guarenteed to have been generated from the requirement. A boolean should be returned to indicate whether `candidate` is a viable solution to the requirement. N)r )r � requirement� candidater r r �is_satisfied_byC s z AbstractProvider.is_satisfied_byc C s t �dS )z�Get dependencies of a candidate. This should return a collection of requirements that `candidate` specifies as its dependencies. N)r )r r r r r �get_dependenciesN s z!AbstractProvider.get_dependenciesN) �__name__� __module__� __qualname__�__doc__r r r r r r r r r r s $ r c @ s$ e Zd ZdZeZdd� Zdd� ZdS )�AbstractResolverz8The thing that performs the actual resolution work. c C s || _ || _d S )N)�provider�reporter)r r r r r r �__init__] s zAbstractResolver.__init__c K s t �dS )a� Take a collection of constraints, spit out the resolution result. This returns a representation of the final resolution state, with one guarenteed attribute ``mapping`` that contains resolved candidates as values. The keys are their respective identifiers. :param requirements: A collection of constraints. :param kwargs: Additional keyword arguments that subclasses may accept. :raises: ``self.base_exception`` or its subclass. N)r )r r �kwargsr r r �resolvea s zAbstractResolver.resolveN)r r r r � ExceptionZbase_exceptionr r r r r r r W s r N)�objectr r r r r r �<module> s V