Source code for packaging.requirements

# 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 string
import re

from pyparsing import stringStart, stringEnd, originalTextFor, ParseException
from pyparsing import ZeroOrMore, Word, Optional, Regex, Combine
from pyparsing import Literal as L  # noqa
from six.moves.urllib import parse as urlparse

from .markers import MARKER_EXPR, Marker
from .specifiers import LegacySpecifier, Specifier, SpecifierSet

[docs]class InvalidRequirement(ValueError): """ An invalid requirement was found, users should refer to PEP 508. """
ALPHANUM = Word(string.ascii_letters + string.digits) LBRACKET = L("[").suppress() RBRACKET = L("]").suppress() LPAREN = L("(").suppress() RPAREN = L(")").suppress() COMMA = L(",").suppress() SEMICOLON = L(";").suppress() AT = L("@").suppress() PUNCTUATION = Word("-_.") IDENTIFIER_END = ALPHANUM | (ZeroOrMore(PUNCTUATION) + ALPHANUM) IDENTIFIER = Combine(ALPHANUM + ZeroOrMore(IDENTIFIER_END)) NAME = IDENTIFIER("name") EXTRA = IDENTIFIER URI = Regex(r'[^ ]+')("url") URL = (AT + URI) EXTRAS_LIST = EXTRA + ZeroOrMore(COMMA + EXTRA) EXTRAS = (LBRACKET + Optional(EXTRAS_LIST) + RBRACKET)("extras") VERSION_PEP440 = Regex(Specifier._regex_str, re.VERBOSE | re.IGNORECASE) VERSION_LEGACY = Regex(LegacySpecifier._regex_str, re.VERBOSE | re.IGNORECASE) VERSION_ONE = VERSION_PEP440 ^ VERSION_LEGACY VERSION_MANY = Combine(VERSION_ONE + ZeroOrMore(COMMA + VERSION_ONE), joinString=",", adjacent=False)("_raw_spec") _VERSION_SPEC = Optional(((LPAREN + VERSION_MANY + RPAREN) | VERSION_MANY)) _VERSION_SPEC.setParseAction(lambda s, l, t: t._raw_spec or '') VERSION_SPEC = originalTextFor(_VERSION_SPEC)("specifier") VERSION_SPEC.setParseAction(lambda s, l, t: t[1]) MARKER_EXPR = originalTextFor(MARKER_EXPR())("marker") MARKER_EXPR.setParseAction( lambda s, l, t: Marker(s[t._original_start:t._original_end]) ) MARKER_SEPARATOR = SEMICOLON MARKER = MARKER_SEPARATOR + MARKER_EXPR VERSION_AND_MARKER = VERSION_SPEC + Optional(MARKER) URL_AND_MARKER = URL + Optional(MARKER) NAMED_REQUIREMENT = \ NAME + Optional(EXTRAS) + (URL_AND_MARKER | VERSION_AND_MARKER) REQUIREMENT = stringStart + NAMED_REQUIREMENT + stringEnd # pyparsing isn't thread safe during initialization, so we do it eagerly, see # issue #104 REQUIREMENT.parseString("x[]")
[docs]class Requirement(object): """Parse a requirement. Parse a given requirement string into its parts, such as name, specifier, URL, and extras. Raises InvalidRequirement on a badly-formed requirement string. """ # TODO: Can we test whether something is contained within a requirement? # If so how do we do that? Do we need to test against the _name_ of # the thing as well as the version? What about the markers? # TODO: Can we normalize the name and extra name? def __init__(self, requirement_string): try: req = REQUIREMENT.parseString(requirement_string) except ParseException as e: raise InvalidRequirement( "Invalid requirement, parse error at \"{0!r}\"".format( requirement_string[e.loc:e.loc + 8])) = if req.url: parsed_url = urlparse.urlparse(req.url) if not (parsed_url.scheme and parsed_url.netloc) or ( not parsed_url.scheme and not parsed_url.netloc): raise InvalidRequirement("Invalid URL given") self.url = req.url else: self.url = None self.extras = set(req.extras.asList() if req.extras else []) self.specifier = SpecifierSet(req.specifier) self.marker = req.marker if req.marker else None def __str__(self): parts = [] if self.extras: parts.append("[{0}]".format(",".join(sorted(self.extras)))) if self.specifier: parts.append(str(self.specifier)) if self.url: parts.append("@ {0}".format(self.url)) if self.marker: parts.append("; {0}".format(self.marker)) return "".join(parts) def __repr__(self): return "<Requirement({0!r})>".format(str(self))