blob: 6af14ec4ce49e633d030611c26f0bd9beaf13e6a [file] [log] [blame]
# 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 pkg_resources.extern.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
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
# pkg_resources.extern.pyparsing isn't thread safe during initialization, so we do it eagerly, see
# issue #104
REQUIREMENT.parseString("x[]")
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}')>"