from __future__ import annotations from abc import ABC, abstractmethod class Discover(ABC): """Discover and provide the requested Python interpreter.""" @classmethod def add_parser_arguments(cls, parser): """ Add CLI arguments for this discovery mechanisms. :param parser: the CLI parser """ raise NotImplementedError def __init__(self, options) -> None: """ Create a new discovery mechanism. :param options: the parsed options as defined within :meth:`add_parser_arguments` """ self._has_run = False self._interpreter = None self._env = options.env @abstractmethod def run(self): """ Discovers an interpreter. :return: the interpreter ready to use for virtual environment creation """ raise NotImplementedError @property def interpreter(self): """:return: the interpreter as returned by :meth:`run`, cached""" if self._has_run is False: self._interpreter = self.run() self._has_run = True return self._interpreter __all__ = [ "Discover", ]