25 lines
798 B
Python
25 lines
798 B
Python
import inspect
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from typing import Any
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from types import CoroutineType, GeneratorType
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__all__ = ["is_awaitable"]
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CO_ITERABLE_COROUTINE = inspect.CO_ITERABLE_COROUTINE
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def is_awaitable(value: Any) -> bool:
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"""Return true if object can be passed to an ``await`` expression.
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Instead of testing if the object is an instance of abc.Awaitable, it checks
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the existence of an `__await__` attribute. This is much faster.
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"""
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return (
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# check for coroutine objects
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isinstance(value, CoroutineType)
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# check for old-style generator based coroutine objects
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or isinstance(value, GeneratorType)
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and bool(value.gi_code.co_flags & CO_ITERABLE_COROUTINE)
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# check for other awaitables (e.g. futures)
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or hasattr(value, "__await__")
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)
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