# This file is dual licensed under the terms of the Apache License, Version
# 2.0, and the BSD License. See the LICENSE file in the root of this repository
# for complete details.
from __future__ import absolute_import, division, print_function
import abc
import functools
import itertools
import re
from ._compat import string_types, with_metaclass
from .version import Version, LegacyVersion, parse
class InvalidSpecifier(ValueError):
"""
An invalid specifier was found, users should refer to PEP 440.
"""
class BaseSpecifier(with_metaclass(abc.ABCMeta, object)):
@abc.abstractmethod
def __str__(self):
"""
Returns the str representation of this Specifier like object. This
should be representative of the Specifier itself.
"""
@abc.abstractmethod
def __hash__(self):
"""
Returns a hash value for this Specifier like object.
"""
@abc.abstractmethod
def __eq__(self, other):
"""
Returns a boolean representing whether or not the two Specifier like
objects are equal.
"""
@abc.abstractmethod
def __ne__(self, other):
"""
Returns a boolean representing whether or not the two Specifier like
objects are not equal.
"""
@abc.abstractproperty
def prereleases(self):
"""
Returns whether or not pre-releases as a whole are allowed by this
specifier.
"""
@prereleases.setter
def prereleases(self, value):
"""
Sets whether or not pre-releases as a whole are allowed by this
specifier.
"""
@abc.abstractmethod
def contains(self, item, prereleases=None):
"""
Determines if the given item is contained within this specifier.
"""
@abc.abstractmethod
def filter(self, iterable, prereleases=None):
"""
Takes an iterable of items and filters them so that only items which
are contained within this specifier are allowed in it.
"""
class _IndividualSpecifier(BaseSpecifier):
_operators = {}
def __init__(self, spec="", prereleases=None):
match = self._regex.search(spec)
if not match:
raise InvalidSpecifier("Invalid specifier: '{0}'".format(spec))
self._spec = (
match.group("operator").strip(),
match.group("version").strip(),
)
# Store whether or not this Specifier should accept prereleases
self._prereleases = prereleases
def __repr__(self):
pre = (
", prereleases={0!r}".format(self.prereleases)
if self._prereleases is not None
else ""
)
return "<{0}({1!r}{2})>".format(
self.__class__.__name__,
str(self),
pre,
)
def __str__(self):
return "{0}{1}".format(*self._spec)
def __hash__(self):
return hash(self._spec)
def __eq__(self, other):
if isinstance(other, string_types):
try:
other = self.__class__(other)
except InvalidSpecifier:
return NotImplemented
elif not isinstance(other, self.__class__):
return NotImplemented
return self._spec == other._spec
def __ne__(self, other):
if isinstance(other, string_types):
try:
other = self.__class__(other)
except InvalidSpecifier:
return NotImplemented
elif not isinstance(other, self.__class__):
return NotImplemented
return self._spec != other._spec
def _get_operator(self, op):
return getattr(self, "_compare_{0}".format(self._operators[op]))
def _coerce_version(self, version):
if not isinstance(version, (LegacyVersion, Version)):
version = parse(version)
return version
@property
def operator(self):
return self._spec[0]
@property
def version(self):
return self._spec[1]
@property
def prereleases(self):
return self._prereleases
@prereleases.setter
def prereleases(self, value):
self._prereleases = value
def __contains__(self, item):
return self.contains(item)
def contains(self, item, prereleases=None):
# Determine if prereleases are to be allowed or not.
if prereleases is None:
prereleases = self.prereleases
# Normalize item to a Version or LegacyVersion, this allows us to have
# a shortcut for ``"2.0" in Specifier(">=2")
item = self._coerce_version(item)
# Determine if we should be supporting prereleases in this specifier
# or not, if we do not support prereleases than we can short circuit
# logic if this version is a prereleases.
if item.is_prerelease and not prereleases:
return False
# Actually do the comparison to determine if this item is contained
# within this Specifier or not.
return self._get_operator(self.operator)(item, self.version)
def filter(self, iterable, prereleases=None):
yielded = False
found_prereleases = []
kw = {"prereleases": prereleases if prereleases is not None else True}
# Attempt to iterate over all the values in the iterable and if any of
# them match, yield them.
for version in iterable:
parsed_version = self._coerce_version(version)
if self.contains(parsed_version, **kw):
# If our version is a prerelease, and we were not set to allow
# prereleases, then we'll store it for later incase nothing
# else matches this specifier.
if (parsed_version.is_prerelease and not
(prereleases or self.prereleases)):
found_prereleases.append(version)
# Either this is not a prerelease, or we should have been
# accepting prereleases from the begining.
else:
yielded = True
yield version
# Now that we've iterated over everything, determine if we've yielded
# any values, and if we have not and we have any prereleases stored up
# then we will go ahead and yield the prereleases.
if not yielded and found_prereleases:
for version in found_prereleases:
yield version
class LegacySpecifier(_IndividualSpecifier):
_regex_str = (
r"""
(?P<operator>(==|!=|<=|>=|<|>))
\s*
(?P<version>
[^,;\s)]* # Since this is a "legacy" specifier, and the version
# string can be just about anything, we match everything
# except for whitespace, a semi-colon for marker support,
# a closing paren since versions can be enclosed in
# them, and a comma since it's a version separator.
)
"""
)
_regex = re.compile(
r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
_operators = {
"==": "equal",
"!=": "not_equal",
"<=": "less_than_equal",
">=": "greater_than_equal",
"<": "less_than",
">": "greater_than",
}
def _coerce_version(self, version):
if not isinstance(version, LegacyVersion):
version = LegacyVersion(str(version))
return version
def _compare_equal(self, prospective, spec):
return prospective == self._coerce_version(spec)
def _compare_not_equal(self, prospective, spec):
return prospective != self._coerce_version(spec)
def _compare_less_than_equal(self, prospective, spec):
return prospective <= self._coerce_version(spec)
def _compare_greater_than_equal(self, prospective, spec):
return prospective >= self._coerce_version(spec)
def _compare_less_than(self, prospective, spec):
return prospective < self._coerce_version(spec)
def _compare_greater_than(self, prospective, spec):
return prospective > self._coerce_version(spec)
def _require_version_compare(fn):
@functools.wraps(fn)
def wrapped(self, prospective, spec):
if not isinstance(prospective, Version):
return False
return fn(self, prospective, spec)
return wrapped
class Specifier(_IndividualSpecifier):
_regex_str = (
r"""
(?P<operator>(~=|==|!=|<=|>=|<|>|===))
(?P<version>
(?:
# The identity operators allow for an escape hatch that will
# do an exact string match of the version you wish to install.
# This will not be parsed by PEP 440 and we cannot determine
# any semantic meaning from it. This operator is discouraged
# but included entirely as an escape hatch.
(?<====) # Only match for the identity operator
\s*
[^\s]* # We just match everything, except for whitespace
# since we are only testing for strict identity.
)
|
(?:
# The (non)equality operators allow for wild card and local
# versions to be specified so we have to define these two
# operators separately to enable that.
(?<===|!=) # Only match for equals and not equals
\s*
v?
(?:[0-9]+!)? # epoch
[0-9]+(?:\.[0-9]+)* # release
(?: # pre release
[-_\.]?
(a|b|c|rc|alpha|beta|pre|preview)
[-_\.]?
[0-9]*
)?
(?: # post release
(?:-[0-9]+)|(?:[-_\.]?(post|rev|r)[-_\.]?[0-9]*)
)?
# You cannot use a wild card and a dev or local version
# together so group them with a | and make them optional.
(?:
(?:[-_\.]?dev[-_\.]?[0-9]*)? # dev release
(?:\+[a-z0-9]+(?:[-_\.][a-z0-9]+)*)? # local
|
\.\* # Wild card syntax of .*
)?
)
|
(?:
# The compatible operator requires at least two digits in the
# release segment.
(?<=~=) # Only match for the compatible operator
\s*
v?
(?:[0-9]+!)? # epoch
[0-9]+(?:\.[0-9]+)+ # release (We have a + instead of a *)
(?: # pre release
[-_\.]?
(a|b|c|rc|alpha|beta|pre|preview)
[-_\.]?
[0-9]*
)?
(?: # post release
(?:-[0-9]+)|(?:[-_\.]?(post|rev|r)[-_\.]?[0-9]*)
)?
(?:[-_\.]?dev[-_\.]?[0-9]*)? # dev release
)
|
(?:
# All other operators only allow a sub set of what the
# (non)equality operators do. Specifically they do not allow
# local versions to be specified nor do they allow the prefix
# matching wild cards.
(?<!==|!=|~=) # We have special cases for these
# operators so we want to make sure they
# don't match here.
\s*
v?
(?:[0-9]+!)? # epoch
[0-9]+(?:\.[0-9]+)* # release
(?: # pre release
[-_\.]?
(a|b|c|rc|alpha|beta|pre|preview)
[-_\.]?
[0-9]*
)?
(?: # post release
(?:-[0-9]+)|(?:[-_\.]?(post|rev|r)[-_\.]?[0-9]*)
)?
(?:[-_\.]?dev[-_\.]?[0-9]*)? # dev release
)
)
"""
)
_regex = re.compile(
r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
_operators = {
"~=": "compatible",
"==": "equal",
"!=": "not_equal",
"<=": "less_than_equal",
">=": "greater_than_equal",
"<": "less_than",
">": "greater_than",
"===": "arbitrary",
}
@_require_version_compare
def _compare_compatible(self, prospective, spec):
# Compatible releases have an equivalent combination of >= and ==. That
# is that ~=2.2 is equivalent to >=2.2,==2.*. This allows us to
# implement this in terms of the other specifiers instead of
# implementing it ourselves. The only thing we need to do is construct
# the other specifiers.
# We want everything but the last item in the version, but we want to
# ignore post and dev releases and we want to treat the pre-release as
# it's own separate segment.
prefix = ".".join(
list(
itertools.takewhile(
lambda x: (not x.startswith("post") and not
x.startswith("dev")),
_version_split(spec),
)
)[:-1]
)
# Add the prefix notation to the end of our string
prefix += ".*"
return (self._get_operator(">=")(prospective, spec) and
self._get_operator("==")(prospective, prefix))
@_require_version_compare
def _compare_equal(self, prospective, spec):
# We need special logic to handle prefix matching
if spec.endswith(".*"):
# In the case of prefix matching we want to ignore local segment.
prospective = Version(prospective.public)
# Split the spec out by dots, and pretend that there is an implicit
# dot in between a release segment and a pre-release segment.
spec = _version_split(spec[:-2]) # Remove the trailing .*
# Split the prospective version out by dots, and pretend that there
# is an implicit dot in between a release segment and a pre-release
# segment.
prospective = _version_split(str(prospective))
# Shorten the prospective version to be the same length as the spec
# so that we can determine if the specifier is a prefix of the
# prospective version or not.
prospective = prospective[:len(spec)]
# Pad out our two sides with zeros so that they both equal the same
# length.
spec, prospective = _pad_version(spec, prospective)
else:
# Convert our spec string into a Version
spec = Version(spec)
# If the specifier does not have a local segment, then we want to
# act as if the prospective version also does not have a local
# segment.
if not spec.local:
prospective = Version(prospective.public)
return prospective == spec
@_require_version_compare
def _compare_not_equal(self, prospective, spec):
return not self._compare_equal(prospective, spec)
@_require_version_compare
def _compare_less_than_equal(self, prospective, spec):
return prospective <= Version(spec)
@_require_version_compare
def _compare_greater_than_equal(self, prospective, spec):
return prospective >= Version(spec)
@_require_version_compare
def _compare_less_than(self, prospective, spec):
# Convert our spec to a Version instance, since we'll want to work with
# it as a version.
spec = Version(spec)
# Check to see if the prospective version is less than the spec
# version. If it's not we can short circuit and just return False now
# instead of doing extra unneeded work.
if not prospective < spec:
return False
# This special case is here so that, unless the specifier itself
# includes is a pre-release version, that we do not accept pre-release
# versions for the version mentioned in the specifier (e.g. <3.1 should
# not match 3.1.dev0, but should match 3.0.dev0).
if not spec.is_prerelease and prospective.is_prerelease:
if Version(prospective.base_version) == Version(spec.base_version):
return False
# If we've gotten to here, it means that prospective version is both
# less than the spec version *and* it's not a pre-release of the same
# version in the spec.
return True
@_require_version_compare
def _compare_greater_than(self, prospective, spec):
# Convert our spec to a Version instance, since we'll want to work with
# it as a version.
spec = Version(spec)
# Check to see if the prospective version is greater than the spec
# version. If it's not we can short circuit and just return False now
# instead of doing extra unneeded work.
if not prospective > spec:
return False
# This special case is here so that, unless the specifier itself
# includes is a post-release version, that we do not accept
# post-release versions for the version mentioned in the specifier
# (e.g. >3.1 should not match 3.0.post0, but should match 3.2.post0).
if not spec.is_postrelease and prospective.is_postrelease:
if Version(prospective.base_version) == Version(spec.base_version):
return False
# Ensure that we do not allow a local version of the version mentioned
# in the specifier, which is techincally greater than, to match.
if prospective.local is not None:
if Version(prospective.base_version) == Version(spec.base_version):
return False
# If we've gotten to here, it means that prospective version is both
# greater than the spec version *and* it's not a pre-release of the
# same version in the spec.
return True
def _compare_arbitrary(self, prospective, spec):
return str(prospective).lower() == str(spec).lower()
@property
def prereleases(self):
# If there is an explicit prereleases set for this, then we'll just
# blindly use that.
if self._prereleases is not None:
return self._prereleases
# Look at all of our specifiers and determine if they are inclusive
# operators, and if they are if they are including an explicit
# prerelease.
operator, version = self._spec
if operator in ["==", ">=", "<=", "~=", "==="]:
# The == specifier can include a trailing .*, if it does we
# want to remove before parsing.
if operator == "==" and version.endswith(".*"):
version = version[:-2]
# Parse the version, and if it is a pre-release than this
# specifier allows pre-releases.
if parse(version).is_prerelease:
return True
return False
@prereleases.setter
def prereleases(self, value):
self._prereleases = value
_prefix_regex = re.compile(r"^([0-9]+)((?:a|b|c|rc)[0-9]+)$")
def _version_split(version):
result = []
for item in version.split("."):
match = _prefix_regex.search(item)
if match:
result.extend(match.groups())
else:
result.append(item)
return result
def _pad_version(left, right):
left_split, right_split = [], []
# Get the release segment of our versions
left_split.append(list(itertools.takewhile(lambda x: x.isdigit(), left)))
right_split.append(list(itertools.takewhile(lambda x: x.isdigit(), right)))
# Get the rest of our versions
left_split.append(left[len(left_split[0]):])
right_split.append(right[len(right_split[0]):])
# Insert our padding
left_split.insert(
1,
["0"] * max(0, len(right_split[0]) - len(left_split[0])),
)
right_split.insert(
1,
["0"] * max(0, len(left_split[0]) - len(right_split[0])),
)
return (
list(itertools.chain(*left_split)),
list(itertools.chain(*right_split)),
)
class SpecifierSet(BaseSpecifier):
def __init__(self, specifiers="", prereleases=None):
# Split on , to break each indidivual specifier into it's own item, and
# strip each item to remove leading/trailing whitespace.
specifiers = [s.strip() for s in specifiers.split(",") if s.strip()]
# Parsed each individual specifier, attempting first to make it a
# Specifier and falling back to a LegacySpecifier.
parsed = set()
for specifier in specifiers:
try:
parsed.add(Specifier(specifier))
except InvalidSpecifier:
parsed.add(LegacySpecifier(specifier))
# Turn our parsed specifiers into a frozen set and save them for later.
self._specs = frozenset(parsed)
# Store our prereleases value so we can use it later to determine if
# we accept prereleases or not.
self._prereleases = prereleases
def __repr__(self):
pre = (
", prereleases={0!r}".format(self.prereleases)
if self._prereleases is not None
else ""
)
return "<SpecifierSet({0!r}{1})>".format(str(self), pre)
def __str__(self):
return ",".join(sorted(str(s) for s in self._specs))
def __hash__(self):
return hash(self._specs)
def __and__(self, other):
if isinstance(other, string_types):
other = SpecifierSet(other)
elif not isinstance(other, SpecifierSet):
return NotImplemented
specifier = SpecifierSet()
specifier._specs = frozenset(self._specs | other._specs)
if self._prereleases is None and other._prereleases is not None:
specifier._prereleases = other._prereleases
elif self._prereleases is not None and other._prereleases is None:
specifier._prereleases = self._prereleases
elif self._prereleases == other._prereleases:
specifier._prereleases = self._prereleases
else:
raise ValueError(
"Cannot combine SpecifierSets with True and False prerelease "
"overrides."
)
return specifier
def __eq__(self, other):
if isinstance(other, string_types):
other = SpecifierSet(other)
elif isinstance(other, _IndividualSpecifier):
other = SpecifierSet(str(other))
elif not isinstance(other, SpecifierSet):
return NotImplemented
return self._specs == other._specs
def __ne__(self, other):
if isinstance(other, string_types):
other = SpecifierSet(other)
elif isinstance(other, _IndividualSpecifier):
other = SpecifierSet(str(other))
elif not isinstance(other, SpecifierSet):
return NotImplemented
return self._specs != other._specs
def __len__(self):
return len(self._specs)
def __iter__(self):
return iter(self._specs)
@property
def prereleases(self):
# If we have been given an explicit prerelease modifier, then we'll
# pass that through here.
if self._prereleases is not None:
return self._prereleases
# If we don't have any specifiers, and we don't have a forced value,
# then we'll just return None since we don't know if this should have
# pre-releases or not.
if not self._specs:
return None
# Otherwise we'll see if any of the given specifiers accept
# prereleases, if any of them do we'll return True, otherwise False.
return any(s.prereleases for s in self._specs)
@prereleases.setter
def prereleases(self, value):
self._prereleases = value
def __contains__(self, item):
return self.contains(item)
def contains(self, item, prereleases=None):
# Ensure that our item is a Version or LegacyVersion instance.
if not isinstance(item, (LegacyVersion, Version)):
item = parse(item)
# Determine if we're forcing a prerelease or not, if we're not forcing
# one for this particular filter call, then we'll use whatever the
# SpecifierSet thinks for whether or not we should support prereleases.
if prereleases is None:
prereleases = self.prereleases
# We can determine if we're going to allow pre-releases by looking to
# see if any of the underlying items supports them. If none of them do
# and this item is a pre-release then we do not allow it and we can
# short circuit that here.
# Note: This means that 1.0.dev1 would not be contained in something
# like >=1.0.devabc however it would be in >=1.0.debabc,>0.0.dev0
if not prereleases and item.is_prerelease:
return False
# We simply dispatch to the underlying specs here to make sure that the
# given version is contained within all of them.
# Note: This use of all() here means that an empty set of specifiers
# will always return True, this is an explicit design decision.
return all(
s.contains(item, prereleases=prereleases)
for s in self._specs
)
def filter(self, iterable, prereleases=None):
# Determine if we're forcing a prerelease or not, if we're not forcing
# one for this particular filter call, then we'll use whatever the
# SpecifierSet thinks for whether or not we should support prereleases.
if prereleases is None:
prereleases = self.prereleases
# If we have any specifiers, then we want to wrap our iterable in the
# filter method for each one, this will act as a logical AND amongst
# each specifier.
if self._specs:
for spec in self._specs:
iterable = spec.filter(iterable, prereleases=bool(prereleases))
return iterable
# If we do not have any specifiers, then we need to have a rough filter
# which will filter out any pre-releases, unless there are no final
# releases, and which will filter out LegacyVersion in general.
else:
filtered = []
found_prereleases = []
for item in iterable:
# Ensure that we some kind of Version class for this item.
if not isinstance(item, (LegacyVersion, Version)):
parsed_version = parse(item)
else:
parsed_version = item
# Filter out any item which is parsed as a LegacyVersion
if isinstance(parsed_version, LegacyVersion):
continue
# Store any item which is a pre-release for later unless we've
# already found a final version or we are accepting prereleases
if parsed_version.is_prerelease and not prereleases:
if not filtered:
found_prereleases.append(item)
else:
filtered.append(item)
# If we've found no items except for pre-releases, then we'll go
# ahead and use the pre-releases
if not filtered and found_prereleases and prereleases is None:
return found_prereleases
return filtered