Source code for pyscaffold.dependencies

"""Internal library for manipulating package dependencies and requirements."""

import re
from itertools import chain
from typing import Iterable, List

from packaging.requirements import InvalidRequirement, Requirement

# setuptools version is now enforced via `install_requires`

BUILD = ("setuptools_scm>=5",)
"""Dependencies that will be required to build the created project"""
RUNTIME = ('importlib-metadata; python_version<"3.8"',)
# TODO: Remove `importlib-metadata` when `python_requires = >= 3.8`
"""Dependencies that will be required at runtime by the created project"""
ISOLATED = ("setuptools>=46.1.0", "setuptools_scm[toml]>=5", *BUILD[1:])
"""Dependencies for isolated builds (:pep:`517`/:pep:`518`).
- setuptools min version might be slightly higher then the version required at runtime.
- setuptools_scm requires an optional dependency to work with pyproject.toml
# Although version 36.6.0 introduces PEP517 implementation,
# version 46.1.0 fix a bug with setuptools.finalize_distribution_options,
# which is a hook used by setuptools_scm (better safe then sorry).

REQ_SPLITTER = re.compile(r";(?!\s*(python|platform|implementation|os|sys)_)", re.M)
"""Regex to split requirements that considers both `setup.cfg specs`_ and :pep:`508`
(in a *good enough* simplified fashion).

.. _setup.cfg specs:
"""  # noqa

[docs]def split(requirements: str) -> List[str]: """Split a combined requirement string (such as the values for ``setup_requires`` and ``install_requires`` in ``setup.cfg``) into a list of individual requirement strings, that can be used in :obj:`is_included`, :obj:`get_requirements_str`, :obj:`remove`, etc... """ lines = requirements.splitlines() deps = (dep.strip() for line in lines for dep in REQ_SPLITTER.split(line) if dep) return [dep for dep in deps if dep] # Remove empty deps
[docs]def deduplicate(requirements: Iterable[str]) -> List[str]: """Given a sequence of individual requirement strings, e.g. ``["platformdirs>=1.4.4", "packaging>20.0"]``, remove the duplicated packages. If a package is duplicated, the last occurrence stays. """ return list({attempt_pkg_name(r): r for r in requirements}.values())
[docs]def remove(requirements: Iterable[str], to_remove: Iterable[str]) -> List[str]: """Given a list of individual requirement strings, e.g. ``["platformdirs>=1.4.4", "packaging>20.0"]``, remove the requirements in ``to_remove``. """ removable = {attempt_pkg_name(r) for r in to_remove} return [r for r in requirements if attempt_pkg_name(r) not in removable]
[docs]def add(requirements: Iterable[str], to_add: Iterable[str] = BUILD) -> List[str]: """Given a sequence of individual requirement strings, add ``to_add`` to it. By default adds :obj:`BUILD` if ``to_add`` is not given.""" return deduplicate(chain(requirements, to_add))
[docs]def attempt_pkg_name(requirement: str) -> str: """In the case the given string is a dependency specification (:pep:`508`/ :pep`440`), it returns the "package name" part of dependency (without versions). Otherwise, it returns the same string (removed the comment marks). """ req = requirement.strip("#").strip() try: return Requirement(req).name except InvalidRequirement: return req