from functools import lru_cache from typing import Callable, Iterable, Iterator, TypeVar, Union, overload import setuptools.extern.jaraco.text as text from setuptools.extern.packaging.requirements import Requirement _T = TypeVar("_T") _StrOrIter = Union[str, Iterable[str]] parse_req: Callable[[str], Requirement] = lru_cache()(Requirement) # Setuptools parses the same requirement many times # (e.g. first for validation than for normalisation), # so it might be worth to cache. def parse_strings(strs: _StrOrIter) -> Iterator[str]: """ Yield requirement strings for each specification in `strs`. `strs` must be a string, or a (possibly-nested) iterable thereof. """ return text.join_continuation(map(text.drop_comment, text.yield_lines(strs))) @overload def parse(strs: _StrOrIter) -> Iterator[Requirement]: ... @overload def parse(strs: _StrOrIter, parser: Callable[[str], _T]) -> Iterator[_T]: ... def parse(strs, parser=parse_req): """ Replacement for ``pkg_resources.parse_requirements`` that uses ``packaging``. """ return map(parser, parse_strings(strs))