1 # typelib.py - type hint aliases and support

     2 #

     3 # Copyright 2022 Matt Harbison <matt_harbison@yahoo.com>

     4 #

     5 # This software may be used and distributed according to the terms of the

     6 # GNU General Public License version 2 or any later version.

     7 

     8 import typing

     9 

    10 # Note: this is slightly different from pycompat.TYPE_CHECKING, as using

    11 # pycompat causes the BinaryIO_Proxy type to be resolved to ``object`` when

    12 # used as the base class during a pytype run.

    13 TYPE_CHECKING = typing.TYPE_CHECKING

    14 

    15 

    16 # The BinaryIO class provides empty methods, which at runtime means that

    17 # ``__getattr__`` on the proxy classes won't get called for the methods that

    18 # should delegate to the internal object.  So to avoid runtime changes because

    19 # of the required typing inheritance, just use BinaryIO when typechecking, and

    20 # ``object`` otherwise.

    21 if TYPE_CHECKING:

    22     from typing import (

    23         BinaryIO,

    24     )

    25 

    26     BinaryIO_Proxy = BinaryIO

    27 else:

    28     BinaryIO_Proxy = object