mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-07-31 23:23:11 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

bpo-44806: Fix __init__ in subclasses of protocols (GH-27545)

Browse source 
Non-protocol subclasses of protocol ignore now the __init__ method
inherited from protocol base classes.
(cherry picked from commit 043cd60abe)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
This commit is contained in:
Miss Islington (bot) 2021-08-02 10:08:59 -07:00 • committed by GitHub
parent 9de590151d
commit 2cc19a5463
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
3 changed files with 48 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

12
Lib/typing.py
View file

@ -1379,8 +1379,7 @@ def _is_callable_members_only(cls):
def _no_init(self, *args, **kwargs):
if type(self)._is_protocol:
raise TypeError('Protocols cannot be instantiated')
raise TypeError('Protocols cannot be instantiated')
def _caller(depth=1, default='__main__'):
try:
@ -1523,6 +1522,15 @@ class Protocol(Generic, metaclass=_ProtocolMeta):
# We have nothing more to do for non-protocols...
if not cls._is_protocol:
if cls.__init__ == _no_init:
for base in cls.__mro__:
init = base.__dict__.get('__init__', _no_init)
if init != _no_init:
cls.__init__ = init
break
else:
# should not happen
cls.__init__ = object.__init__
return
# ... otherwise check consistency of bases, and prohibit instantiation.