32 lines
791 B
Python
32 lines
791 B
Python
from __future__ import annotations
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from typing import NoReturn, TypeVar
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from attrs import define as _define, frozen as _frozen
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_T = TypeVar("_T")
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def define(cls: type[_T]) -> type[_T]: # pragma: no cover
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cls.__init_subclass__ = _do_not_subclass
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return _define(cls)
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def frozen(cls: type[_T]) -> type[_T]:
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cls.__init_subclass__ = _do_not_subclass
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return _frozen(cls)
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class UnsupportedSubclassing(Exception):
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def __str__(self):
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return (
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"Subclassing is not part of referencing's public API. "
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"If no other suitable API exists for what you're trying to do, "
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"feel free to file an issue asking for one."
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)
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@staticmethod
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def _do_not_subclass() -> NoReturn: # pragma: no cover
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raise UnsupportedSubclassing()
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