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.

import re
import string
import urllib.parse
from typing import List, Optional as TOptional, Set

from pyparsing import (  # noqa
    Combine,
    Literal as L,
    Optional,
    ParseException,
    Regex,
    Word,
    ZeroOrMore,
    originalTextFor,
    stringEnd,
    stringStart,
)

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: """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: str) -> None: try: req = REQUIREMENT.parseString(requirement_string) except ParseException as e: raise InvalidRequirement( f'Parse error at "{ requirement_string[e.loc : e.loc + 8]!r}": {e.msg}' ) self.name: str = req.name if req.url: parsed_url = urllib.parse.urlparse(req.url) if parsed_url.scheme == "file": if urllib.parse.urlunparse(parsed_url) != req.url: raise InvalidRequirement("Invalid URL given") elif not (parsed_url.scheme and parsed_url.netloc) or ( not parsed_url.scheme and not parsed_url.netloc ): raise InvalidRequirement(f"Invalid URL: {req.url}") self.url: TOptional[str] = req.url else: self.url = None self.extras: Set[str] = set(req.extras.asList() if req.extras else []) self.specifier: SpecifierSet = SpecifierSet(req.specifier) self.marker: TOptional[Marker] = req.marker if req.marker else None def __str__(self) -> str: parts: List[str] = [self.name] if self.extras: formatted_extras = ",".join(sorted(self.extras)) parts.append(f"[{formatted_extras}]") if self.specifier: parts.append(str(self.specifier)) if self.url: parts.append(f"@ {self.url}") if self.marker: parts.append(" ") if self.marker: parts.append(f"; {self.marker}") return "".join(parts) def __repr__(self) -> str: return f"<Requirement('{self}')>"