Source code for class_resolver.utils

# -*- coding: utf-8 -*-

"""Utilities for the resolver."""

import logging
from typing import (

    import click  # pragma: no cover

__all__ = [
    # Type Hints
    # Functions

logger = logging.getLogger(__name__)

X = TypeVar("X")
Y = TypeVar("Y")

#: A type annotation for either an instance of X or a class of X
InstOrType = Union[X, Type[X]]
#: A type annotation for either an instance of X or name a class X
Lookup = Union[str, X]

LookupType = Lookup[Type[X]]
LookupOrType = Lookup[InstOrType[X]]
Hint = Optional[Lookup[X]]
HintType = Hint[Type[X]]
HintOrType = Hint[InstOrType[X]]
OptionalKwargs = Optional[Mapping[str, Any]]
OneOrSequence = Union[X, Sequence[X]]
OneOrManyHintOrType = Optional[OneOrSequence[HintOrType[X]]]
OneOrManyOptionalKwargs = Optional[OneOrSequence[OptionalKwargs]]

def get_subclasses(
    cls: Type[X],
    exclude_private: bool = True,
    exclude_external: bool = True,
) -> Iterable[Type[X]]:
    """Get all subclasses.

    :param cls: The ancestor class
    :param exclude_private: If true, will skip any class that comes from a module
        starting with an underscore (i.e., a private module). This is typically
        done when having shadow duplicate classes implemented in C
    :param exclude_external: If true, will exclude any class that does not originate
        from the same package as the base class.
    :yields: Descendant classes of the ancestor class
    for subclass in cls.__subclasses__():
        yield from get_subclasses(subclass)
        if exclude_private:
            if any(part.startswith("_") for part in subclass.__module__.split(".")):
            if subclass.__name__.startswith("_"):
        if exclude_external and not same_module(cls, subclass):
        yield subclass

def same_module(cls1: type, cls2: type) -> bool:
    """Return if two classes come from the same module via the ``__module__`` attribute."""
    return cls1.__module__.split(".")[0] == cls2.__module__.split(".")[0]

[docs]def normalize_string(s: str, *, suffix: Optional[str] = None) -> str: """Normalize a string for lookup.""" s = s.lower().replace("-", "").replace("_", "").replace(" ", "") if suffix is not None and s.endswith(suffix.lower()): return s[: -len(suffix)] return s.strip()
def upgrade_to_sequence(x: Union[X, Sequence[X]]) -> Sequence[X]: """Ensure that the input is a sequence. :param x: A literal or sequence of literals (don't consider a string x as a sequence) :return: If a literal was given, a one element tuple with it in it. Otherwise, return the given value. >>> upgrade_to_sequence(1) (1,) >>> upgrade_to_sequence((1, 2, 3)) (1, 2, 3) >>> upgrade_to_sequence("test") ('test',) >>> upgrade_to_sequence(tuple("test")) ('t', 'e', 's', 't') """ if isinstance(x, str): return (x,) # type: ignore elif isinstance(x, return x else: return (x,) def make_callback(f: Callable[[X], Y]) -> Callable[["click.Context", "click.Parameter", X], Y]: """Make a click-appropriate callback.""" def _callback(_ctx: "click.Context", _param: "click.Parameter", value: X) -> Y: return f(value) return _callback def normalize_with_default( choice: HintOrType[X], kwargs: OptionalKwargs = None, default: HintOrType[X] = None, default_kwargs: OptionalKwargs = None, ) -> Tuple[HintOrType[X], OptionalKwargs]: """ Normalize a choice for class resolver, with default options. :param choice: the choice. If None, use the default instead. :param kwargs: the keyword-based parameters for instantiation. Will only be used if choice is *not* None. :param default: the default choice. Used of choice=None. :param default_kwargs: the default keyword-based parameters :raises ValueError: if choice and default both are None :return: a pair (hint, optional kwargs). """ if choice is None: if default is None: raise ValueError("If choice is None, a default has to be provided.") choice = default if kwargs is not None: logger.warning( f"No choice was provided, but kwargs={kwargs} is not None. Will use the default choice={default} " f"with its default_kwargs={default_kwargs}. If you want the explicitly provided kwargs to be used," f" explicitly provide choice={default} instead of None." ) kwargs = default_kwargs return choice, kwargs