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1# This file is dual licensed under the terms of the Apache License, Version
2# 2.0, and the BSD License. See the LICENSE file in the root of this repository
3# for complete details.
4from __future__ import absolute_import, division, print_function
5
6import abc
7import functools
8import itertools
9import re
10
11from ._compat import string_types, with_metaclass
12from .version import Version, LegacyVersion, parse
13
14
15class InvalidSpecifier(ValueError):
16 """
17 An invalid specifier was found, users should refer to PEP 440.
18 """
19
20
21class BaseSpecifier(with_metaclass(abc.ABCMeta, object)):
22
23 @abc.abstractmethod
24 def __str__(self):
25 """
26 Returns the str representation of this Specifier like object. This
27 should be representative of the Specifier itself.
28 """
29
30 @abc.abstractmethod
31 def __hash__(self):
32 """
33 Returns a hash value for this Specifier like object.
34 """
35
36 @abc.abstractmethod
37 def __eq__(self, other):
38 """
39 Returns a boolean representing whether or not the two Specifier like
40 objects are equal.
41 """
42
43 @abc.abstractmethod
44 def __ne__(self, other):
45 """
46 Returns a boolean representing whether or not the two Specifier like
47 objects are not equal.
48 """
49
50 @abc.abstractproperty
51 def prereleases(self):
52 """
53 Returns whether or not pre-releases as a whole are allowed by this
54 specifier.
55 """
56
57 @prereleases.setter
58 def prereleases(self, value):
59 """
60 Sets whether or not pre-releases as a whole are allowed by this
61 specifier.
62 """
63
64 @abc.abstractmethod
65 def contains(self, item, prereleases=None):
66 """
67 Determines if the given item is contained within this specifier.
68 """
69
70 @abc.abstractmethod
71 def filter(self, iterable, prereleases=None):
72 """
73 Takes an iterable of items and filters them so that only items which
74 are contained within this specifier are allowed in it.
75 """
76
77
78class _IndividualSpecifier(BaseSpecifier):
79
80 _operators = {}
81
82 def __init__(self, spec="", prereleases=None):
83 match = self._regex.search(spec)
84 if not match:
85 raise InvalidSpecifier("Invalid specifier: '{0}'".format(spec))
86
87 self._spec = (
88 match.group("operator").strip(),
89 match.group("version").strip(),
90 )
91
92 # Store whether or not this Specifier should accept prereleases
93 self._prereleases = prereleases
94
95 def __repr__(self):
96 pre = (
97 ", prereleases={0!r}".format(self.prereleases)
98 if self._prereleases is not None
99 else ""
100 )
101
102 return "<{0}({1!r}{2})>".format(
103 self.__class__.__name__,
104 str(self),
105 pre,
106 )
107
108 def __str__(self):
109 return "{0}{1}".format(*self._spec)
110
111 def __hash__(self):
112 return hash(self._spec)
113
114 def __eq__(self, other):
115 if isinstance(other, string_types):
116 try:
117 other = self.__class__(other)
118 except InvalidSpecifier:
119 return NotImplemented
120 elif not isinstance(other, self.__class__):
121 return NotImplemented
122
123 return self._spec == other._spec
124
125 def __ne__(self, other):
126 if isinstance(other, string_types):
127 try:
128 other = self.__class__(other)
129 except InvalidSpecifier:
130 return NotImplemented
131 elif not isinstance(other, self.__class__):
132 return NotImplemented
133
134 return self._spec != other._spec
135
136 def _get_operator(self, op):
137 return getattr(self, "_compare_{0}".format(self._operators[op]))
138
139 def _coerce_version(self, version):
140 if not isinstance(version, (LegacyVersion, Version)):
141 version = parse(version)
142 return version
143
144 @property
145 def operator(self):
146 return self._spec[0]
147
148 @property
149 def version(self):
150 return self._spec[1]
151
152 @property
153 def prereleases(self):
154 return self._prereleases
155
156 @prereleases.setter
157 def prereleases(self, value):
158 self._prereleases = value
159
160 def __contains__(self, item):
161 return self.contains(item)
162
163 def contains(self, item, prereleases=None):
164 # Determine if prereleases are to be allowed or not.
165 if prereleases is None:
166 prereleases = self.prereleases
167
168 # Normalize item to a Version or LegacyVersion, this allows us to have
169 # a shortcut for ``"2.0" in Specifier(">=2")
170 item = self._coerce_version(item)
171
172 # Determine if we should be supporting prereleases in this specifier
173 # or not, if we do not support prereleases than we can short circuit
174 # logic if this version is a prereleases.
175 if item.is_prerelease and not prereleases:
176 return False
177
178 # Actually do the comparison to determine if this item is contained
179 # within this Specifier or not.
180 return self._get_operator(self.operator)(item, self.version)
181
182 def filter(self, iterable, prereleases=None):
183 yielded = False
184 found_prereleases = []
185
186 kw = {"prereleases": prereleases if prereleases is not None else True}
187
188 # Attempt to iterate over all the values in the iterable and if any of
189 # them match, yield them.
190 for version in iterable:
191 parsed_version = self._coerce_version(version)
192
193 if self.contains(parsed_version, **kw):
194 # If our version is a prerelease, and we were not set to allow
195 # prereleases, then we'll store it for later incase nothing
196 # else matches this specifier.
197 if (parsed_version.is_prerelease and not
198 (prereleases or self.prereleases)):
199 found_prereleases.append(version)
200 # Either this is not a prerelease, or we should have been
201 # accepting prereleases from the beginning.
202 else:
203 yielded = True
204 yield version
205
206 # Now that we've iterated over everything, determine if we've yielded
207 # any values, and if we have not and we have any prereleases stored up
208 # then we will go ahead and yield the prereleases.
209 if not yielded and found_prereleases:
210 for version in found_prereleases:
211 yield version
212
213
214class LegacySpecifier(_IndividualSpecifier):
215
216 _regex_str = (
217 r"""
218 (?P<operator>(==|!=|<=|>=|<|>))
219 \s*
220 (?P<version>
221 [^,;\s)]* # Since this is a "legacy" specifier, and the version
222 # string can be just about anything, we match everything
223 # except for whitespace, a semi-colon for marker support,
224 # a closing paren since versions can be enclosed in
225 # them, and a comma since it's a version separator.
226 )
227 """
228 )
229
230 _regex = re.compile(
231 r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
232
233 _operators = {
234 "==": "equal",
235 "!=": "not_equal",
236 "<=": "less_than_equal",
237 ">=": "greater_than_equal",
238 "<": "less_than",
239 ">": "greater_than",
240 }
241
242 def _coerce_version(self, version):
243 if not isinstance(version, LegacyVersion):
244 version = LegacyVersion(str(version))
245 return version
246
247 def _compare_equal(self, prospective, spec):
248 return prospective == self._coerce_version(spec)
249
250 def _compare_not_equal(self, prospective, spec):
251 return prospective != self._coerce_version(spec)
252
253 def _compare_less_than_equal(self, prospective, spec):
254 return prospective <= self._coerce_version(spec)
255
256 def _compare_greater_than_equal(self, prospective, spec):
257 return prospective >= self._coerce_version(spec)
258
259 def _compare_less_than(self, prospective, spec):
260 return prospective < self._coerce_version(spec)
261
262 def _compare_greater_than(self, prospective, spec):
263 return prospective > self._coerce_version(spec)
264
265
266def _require_version_compare(fn):
267 @functools.wraps(fn)
268 def wrapped(self, prospective, spec):
269 if not isinstance(prospective, Version):
270 return False
271 return fn(self, prospective, spec)
272 return wrapped
273
274
275class Specifier(_IndividualSpecifier):
276
277 _regex_str = (
278 r"""
279 (?P<operator>(~=|==|!=|<=|>=|<|>|===))
280 (?P<version>
281 (?:
282 # The identity operators allow for an escape hatch that will
283 # do an exact string match of the version you wish to install.
284 # This will not be parsed by PEP 440 and we cannot determine
285 # any semantic meaning from it. This operator is discouraged
286 # but included entirely as an escape hatch.
287 (?<====) # Only match for the identity operator
288 \s*
289 [^\s]* # We just match everything, except for whitespace
290 # since we are only testing for strict identity.
291 )
292 |
293 (?:
294 # The (non)equality operators allow for wild card and local
295 # versions to be specified so we have to define these two
296 # operators separately to enable that.
297 (?<===|!=) # Only match for equals and not equals
298
299 \s*
300 v?
301 (?:[0-9]+!)? # epoch
302 [0-9]+(?:\.[0-9]+)* # release
303 (?: # pre release
304 [-_\.]?
305 (a|b|c|rc|alpha|beta|pre|preview)
306 [-_\.]?
307 [0-9]*
308 )?
309 (?: # post release
310 (?:-[0-9]+)|(?:[-_\.]?(post|rev|r)[-_\.]?[0-9]*)
311 )?
312
313 # You cannot use a wild card and a dev or local version
314 # together so group them with a | and make them optional.
315 (?:
316 (?:[-_\.]?dev[-_\.]?[0-9]*)? # dev release
317 (?:\+[a-z0-9]+(?:[-_\.][a-z0-9]+)*)? # local
318 |
319 \.\* # Wild card syntax of .*
320 )?
321 )
322 |
323 (?:
324 # The compatible operator requires at least two digits in the
325 # release segment.
326 (?<=~=) # Only match for the compatible operator
327
328 \s*
329 v?
330 (?:[0-9]+!)? # epoch
331 [0-9]+(?:\.[0-9]+)+ # release (We have a + instead of a *)
332 (?: # pre release
333 [-_\.]?
334 (a|b|c|rc|alpha|beta|pre|preview)
335 [-_\.]?
336 [0-9]*
337 )?
338 (?: # post release
339 (?:-[0-9]+)|(?:[-_\.]?(post|rev|r)[-_\.]?[0-9]*)
340 )?
341 (?:[-_\.]?dev[-_\.]?[0-9]*)? # dev release
342 )
343 |
344 (?:
345 # All other operators only allow a sub set of what the
346 # (non)equality operators do. Specifically they do not allow
347 # local versions to be specified nor do they allow the prefix
348 # matching wild cards.
349 (?<!==|!=|~=) # We have special cases for these
350 # operators so we want to make sure they
351 # don't match here.
352
353 \s*
354 v?
355 (?:[0-9]+!)? # epoch
356 [0-9]+(?:\.[0-9]+)* # release
357 (?: # pre release
358 [-_\.]?
359 (a|b|c|rc|alpha|beta|pre|preview)
360 [-_\.]?
361 [0-9]*
362 )?
363 (?: # post release
364 (?:-[0-9]+)|(?:[-_\.]?(post|rev|r)[-_\.]?[0-9]*)
365 )?
366 (?:[-_\.]?dev[-_\.]?[0-9]*)? # dev release
367 )
368 )
369 """
370 )
371
372 _regex = re.compile(
373 r"^\s*" + _regex_str + r"\s*$", re.VERBOSE | re.IGNORECASE)
374
375 _operators = {
376 "~=": "compatible",
377 "==": "equal",
378 "!=": "not_equal",
379 "<=": "less_than_equal",
380 ">=": "greater_than_equal",
381 "<": "less_than",
382 ">": "greater_than",
383 "===": "arbitrary",
384 }
385
386 @_require_version_compare
387 def _compare_compatible(self, prospective, spec):
388 # Compatible releases have an equivalent combination of >= and ==. That
389 # is that ~=2.2 is equivalent to >=2.2,==2.*. This allows us to
390 # implement this in terms of the other specifiers instead of
391 # implementing it ourselves. The only thing we need to do is construct
392 # the other specifiers.
393
394 # We want everything but the last item in the version, but we want to
395 # ignore post and dev releases and we want to treat the pre-release as
396 # it's own separate segment.
397 prefix = ".".join(
398 list(
399 itertools.takewhile(
400 lambda x: (not x.startswith("post") and not
401 x.startswith("dev")),
402 _version_split(spec),
403 )
404 )[:-1]
405 )
406
407 # Add the prefix notation to the end of our string
408 prefix += ".*"
409
410 return (self._get_operator(">=")(prospective, spec) and
411 self._get_operator("==")(prospective, prefix))
412
413 @_require_version_compare
414 def _compare_equal(self, prospective, spec):
415 # We need special logic to handle prefix matching
416 if spec.endswith(".*"):
417 # In the case of prefix matching we want to ignore local segment.
418 prospective = Version(prospective.public)
419 # Split the spec out by dots, and pretend that there is an implicit
420 # dot in between a release segment and a pre-release segment.
421 spec = _version_split(spec[:-2]) # Remove the trailing .*
422
423 # Split the prospective version out by dots, and pretend that there
424 # is an implicit dot in between a release segment and a pre-release
425 # segment.
426 prospective = _version_split(str(prospective))
427
428 # Shorten the prospective version to be the same length as the spec
429 # so that we can determine if the specifier is a prefix of the
430 # prospective version or not.
431 prospective = prospective[:len(spec)]
432
433 # Pad out our two sides with zeros so that they both equal the same
434 # length.
435 spec, prospective = _pad_version(spec, prospective)
436 else:
437 # Convert our spec string into a Version
438 spec = Version(spec)
439
440 # If the specifier does not have a local segment, then we want to
441 # act as if the prospective version also does not have a local
442 # segment.
443 if not spec.local:
444 prospective = Version(prospective.public)
445
446 return prospective == spec
447
448 @_require_version_compare
449 def _compare_not_equal(self, prospective, spec):
450 return not self._compare_equal(prospective, spec)
451
452 @_require_version_compare
453 def _compare_less_than_equal(self, prospective, spec):
454 return prospective <= Version(spec)
455
456 @_require_version_compare
457 def _compare_greater_than_equal(self, prospective, spec):
458 return prospective >= Version(spec)
459
460 @_require_version_compare
461 def _compare_less_than(self, prospective, spec):
462 # Convert our spec to a Version instance, since we'll want to work with
463 # it as a version.
464 spec = Version(spec)
465
466 # Check to see if the prospective version is less than the spec
467 # version. If it's not we can short circuit and just return False now
468 # instead of doing extra unneeded work.
469 if not prospective < spec:
470 return False
471
472 # This special case is here so that, unless the specifier itself
473 # includes is a pre-release version, that we do not accept pre-release
474 # versions for the version mentioned in the specifier (e.g. <3.1 should
475 # not match 3.1.dev0, but should match 3.0.dev0).
476 if not spec.is_prerelease and prospective.is_prerelease:
477 if Version(prospective.base_version) == Version(spec.base_version):
478 return False
479
480 # If we've gotten to here, it means that prospective version is both
481 # less than the spec version *and* it's not a pre-release of the same
482 # version in the spec.
483 return True
484
485 @_require_version_compare
486 def _compare_greater_than(self, prospective, spec):
487 # Convert our spec to a Version instance, since we'll want to work with
488 # it as a version.
489 spec = Version(spec)
490
491 # Check to see if the prospective version is greater than the spec
492 # version. If it's not we can short circuit and just return False now
493 # instead of doing extra unneeded work.
494 if not prospective > spec:
495 return False
496
497 # This special case is here so that, unless the specifier itself
498 # includes is a post-release version, that we do not accept
499 # post-release versions for the version mentioned in the specifier
500 # (e.g. >3.1 should not match 3.0.post0, but should match 3.2.post0).
501 if not spec.is_postrelease and prospective.is_postrelease:
502 if Version(prospective.base_version) == Version(spec.base_version):
503 return False
504
505 # Ensure that we do not allow a local version of the version mentioned
506 # in the specifier, which is techincally greater than, to match.
507 if prospective.local is not None:
508 if Version(prospective.base_version) == Version(spec.base_version):
509 return False
510
511 # If we've gotten to here, it means that prospective version is both
512 # greater than the spec version *and* it's not a pre-release of the
513 # same version in the spec.
514 return True
515
516 def _compare_arbitrary(self, prospective, spec):
517 return str(prospective).lower() == str(spec).lower()
518
519 @property
520 def prereleases(self):
521 # If there is an explicit prereleases set for this, then we'll just
522 # blindly use that.
523 if self._prereleases is not None:
524 return self._prereleases
525
526 # Look at all of our specifiers and determine if they are inclusive
527 # operators, and if they are if they are including an explicit
528 # prerelease.
529 operator, version = self._spec
530 if operator in ["==", ">=", "<=", "~=", "==="]:
531 # The == specifier can include a trailing .*, if it does we
532 # want to remove before parsing.
533 if operator == "==" and version.endswith(".*"):
534 version = version[:-2]
535
536 # Parse the version, and if it is a pre-release than this
537 # specifier allows pre-releases.
538 if parse(version).is_prerelease:
539 return True
540
541 return False
542
543 @prereleases.setter
544 def prereleases(self, value):
545 self._prereleases = value
546
547
548_prefix_regex = re.compile(r"^([0-9]+)((?:a|b|c|rc)[0-9]+)$")
549
550
551def _version_split(version):
552 result = []
553 for item in version.split("."):
554 match = _prefix_regex.search(item)
555 if match:
556 result.extend(match.groups())
557 else:
558 result.append(item)
559 return result
560
561
562def _pad_version(left, right):
563 left_split, right_split = [], []
564
565 # Get the release segment of our versions
566 left_split.append(list(itertools.takewhile(lambda x: x.isdigit(), left)))
567 right_split.append(list(itertools.takewhile(lambda x: x.isdigit(), right)))
568
569 # Get the rest of our versions
570 left_split.append(left[len(left_split[0]):])
571 right_split.append(right[len(right_split[0]):])
572
573 # Insert our padding
574 left_split.insert(
575 1,
576 ["0"] * max(0, len(right_split[0]) - len(left_split[0])),
577 )
578 right_split.insert(
579 1,
580 ["0"] * max(0, len(left_split[0]) - len(right_split[0])),
581 )
582
583 return (
584 list(itertools.chain(*left_split)),
585 list(itertools.chain(*right_split)),
586 )
587
588
589class SpecifierSet(BaseSpecifier):
590
591 def __init__(self, specifiers="", prereleases=None):
592 # Split on , to break each indidivual specifier into it's own item, and
593 # strip each item to remove leading/trailing whitespace.
594 specifiers = [s.strip() for s in specifiers.split(",") if s.strip()]
595
596 # Parsed each individual specifier, attempting first to make it a
597 # Specifier and falling back to a LegacySpecifier.
598 parsed = set()
599 for specifier in specifiers:
600 try:
601 parsed.add(Specifier(specifier))
602 except InvalidSpecifier:
603 parsed.add(LegacySpecifier(specifier))
604
605 # Turn our parsed specifiers into a frozen set and save them for later.
606 self._specs = frozenset(parsed)
607
608 # Store our prereleases value so we can use it later to determine if
609 # we accept prereleases or not.
610 self._prereleases = prereleases
611
612 def __repr__(self):
613 pre = (
614 ", prereleases={0!r}".format(self.prereleases)
615 if self._prereleases is not None
616 else ""
617 )
618
619 return "<SpecifierSet({0!r}{1})>".format(str(self), pre)
620
621 def __str__(self):
622 return ",".join(sorted(str(s) for s in self._specs))
623
624 def __hash__(self):
625 return hash(self._specs)
626
627 def __and__(self, other):
628 if isinstance(other, string_types):
629 other = SpecifierSet(other)
630 elif not isinstance(other, SpecifierSet):
631 return NotImplemented
632
633 specifier = SpecifierSet()
634 specifier._specs = frozenset(self._specs | other._specs)
635
636 if self._prereleases is None and other._prereleases is not None:
637 specifier._prereleases = other._prereleases
638 elif self._prereleases is not None and other._prereleases is None:
639 specifier._prereleases = self._prereleases
640 elif self._prereleases == other._prereleases:
641 specifier._prereleases = self._prereleases
642 else:
643 raise ValueError(
644 "Cannot combine SpecifierSets with True and False prerelease "
645 "overrides."
646 )
647
648 return specifier
649
650 def __eq__(self, other):
651 if isinstance(other, string_types):
652 other = SpecifierSet(other)
653 elif isinstance(other, _IndividualSpecifier):
654 other = SpecifierSet(str(other))
655 elif not isinstance(other, SpecifierSet):
656 return NotImplemented
657
658 return self._specs == other._specs
659
660 def __ne__(self, other):
661 if isinstance(other, string_types):
662 other = SpecifierSet(other)
663 elif isinstance(other, _IndividualSpecifier):
664 other = SpecifierSet(str(other))
665 elif not isinstance(other, SpecifierSet):
666 return NotImplemented
667
668 return self._specs != other._specs
669
670 def __len__(self):
671 return len(self._specs)
672
673 def __iter__(self):
674 return iter(self._specs)
675
676 @property
677 def prereleases(self):
678 # If we have been given an explicit prerelease modifier, then we'll
679 # pass that through here.
680 if self._prereleases is not None:
681 return self._prereleases
682
683 # If we don't have any specifiers, and we don't have a forced value,
684 # then we'll just return None since we don't know if this should have
685 # pre-releases or not.
686 if not self._specs:
687 return None
688
689 # Otherwise we'll see if any of the given specifiers accept
690 # prereleases, if any of them do we'll return True, otherwise False.
691 return any(s.prereleases for s in self._specs)
692
693 @prereleases.setter
694 def prereleases(self, value):
695 self._prereleases = value
696
697 def __contains__(self, item):
698 return self.contains(item)
699
700 def contains(self, item, prereleases=None):
701 # Ensure that our item is a Version or LegacyVersion instance.
702 if not isinstance(item, (LegacyVersion, Version)):
703 item = parse(item)
704
705 # Determine if we're forcing a prerelease or not, if we're not forcing
706 # one for this particular filter call, then we'll use whatever the
707 # SpecifierSet thinks for whether or not we should support prereleases.
708 if prereleases is None:
709 prereleases = self.prereleases
710
711 # We can determine if we're going to allow pre-releases by looking to
712 # see if any of the underlying items supports them. If none of them do
713 # and this item is a pre-release then we do not allow it and we can
714 # short circuit that here.
715 # Note: This means that 1.0.dev1 would not be contained in something
716 # like >=1.0.devabc however it would be in >=1.0.debabc,>0.0.dev0
717 if not prereleases and item.is_prerelease:
718 return False
719
720 # We simply dispatch to the underlying specs here to make sure that the
721 # given version is contained within all of them.
722 # Note: This use of all() here means that an empty set of specifiers
723 # will always return True, this is an explicit design decision.
724 return all(
725 s.contains(item, prereleases=prereleases)
726 for s in self._specs
727 )
728
729 def filter(self, iterable, prereleases=None):
730 # Determine if we're forcing a prerelease or not, if we're not forcing
731 # one for this particular filter call, then we'll use whatever the
732 # SpecifierSet thinks for whether or not we should support prereleases.
733 if prereleases is None:
734 prereleases = self.prereleases
735
736 # If we have any specifiers, then we want to wrap our iterable in the
737 # filter method for each one, this will act as a logical AND amongst
738 # each specifier.
739 if self._specs:
740 for spec in self._specs:
741 iterable = spec.filter(iterable, prereleases=bool(prereleases))
742 return iterable
743 # If we do not have any specifiers, then we need to have a rough filter
744 # which will filter out any pre-releases, unless there are no final
745 # releases, and which will filter out LegacyVersion in general.
746 else:
747 filtered = []
748 found_prereleases = []
749
750 for item in iterable:
751 # Ensure that we some kind of Version class for this item.
752 if not isinstance(item, (LegacyVersion, Version)):
753 parsed_version = parse(item)
754 else:
755 parsed_version = item
756
757 # Filter out any item which is parsed as a LegacyVersion
758 if isinstance(parsed_version, LegacyVersion):
759 continue
760
761 # Store any item which is a pre-release for later unless we've
762 # already found a final version or we are accepting prereleases
763 if parsed_version.is_prerelease and not prereleases:
764 if not filtered:
765 found_prereleases.append(item)
766 else:
767 filtered.append(item)
768
769 # If we've found no items except for pre-releases, then we'll go
770 # ahead and use the pre-releases
771 if not filtered and found_prereleases and prereleases is None:
772 return found_prereleases
773
774 return filtered