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# Copyright 2014 Pants project contributors (see CONTRIBUTORS.md).
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# Licensed under the Apache License, Version 2.0 (see LICENSE).
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from __future__ import absolute_import
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from collections import Iterable
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from pkg_resources import Requirement
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from .compatibility import string as compatibility_string
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REQUIRED_ATTRIBUTES = (
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def quacks_like_req(req):
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return all(hasattr(req, attr) for attr in REQUIRED_ATTRIBUTES)
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def maybe_requirement(req):
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if isinstance(req, Requirement) or quacks_like_req(req):
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elif isinstance(req, compatibility_string):
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return Requirement.parse(req)
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raise ValueError('Unknown requirement %r' % (req,))
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def maybe_requirement_list(reqs):
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if isinstance(reqs, (compatibility_string, Requirement)) or quacks_like_req(reqs):
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return [maybe_requirement(reqs)]
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elif isinstance(reqs, Iterable):
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return [maybe_requirement(req) for req in reqs]
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raise ValueError('Unknown requirement list %r' % (reqs,))
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def requirement_is_exact(req):
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return req.specs and len(req.specs) == 1 and req.specs[0][0] == '=='
added
removed
pex/base.py
