req_install.py 文件源码

def __init__(self, req, comes_from, source_dir=None, editable=False,
                 link=None, as_egg=False, update=True, editable_options=None,
                 pycompile=True, markers=None, isolated=False, options=None,
                 wheel_cache=None):
        self.extras = ()
        if isinstance(req, six.string_types):
            req = pkg_resources.Requirement.parse(req)
            self.extras = req.extras

        self.req = req
        self.comes_from = comes_from
        self.source_dir = source_dir
        self.editable = editable

        if editable_options is None:
            editable_options = {}

        self.editable_options = editable_options
        self._wheel_cache = wheel_cache
        self.link = link
        self.as_egg = as_egg
        self.markers = markers
        self._egg_info_path = None
        # This holds the pkg_resources.Distribution object if this requirement
        # is already available:
        self.satisfied_by = None
        # This hold the pkg_resources.Distribution object if this requirement
        # conflicts with another installed distribution:
        self.conflicts_with = None
        # Temporary build location
        self._temp_build_dir = None
        # Used to store the global directory where the _temp_build_dir should
        # have been created. Cf _correct_build_location method.
        self._ideal_global_dir = None
        # True if the editable should be updated:
        self.update = update
        # Set to True after successful installation
        self.install_succeeded = None
        # UninstallPathSet of uninstalled distribution (for possible rollback)
        self.uninstalled = None
        self.use_user_site = False
        self.target_dir = None
        self.options = options if options else {}
        self.pycompile = pycompile

        self.isolated = isolated