From a5e96703d96d78e93df67c748edcf05904bc23bc Mon Sep 17 00:00:00 2001 From: Chris Markiewicz Date: Sat, 23 Mar 2024 11:30:28 -0400 Subject: [PATCH] gh-117182: Allow modules to modify their own __class__ when lazily loaded --- Lib/importlib/util.py | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/Lib/importlib/util.py b/Lib/importlib/util.py index f1bb4b1fb41576..c94a148e4c50e0 100644 --- a/Lib/importlib/util.py +++ b/Lib/importlib/util.py @@ -178,15 +178,17 @@ def __getattribute__(self, attr): # Only the first thread to get the lock should trigger the load # and reset the module's class. The rest can now getattr(). if object.__getattribute__(self, '__class__') is _LazyModule: + __class__ = loader_state['__class__'] + # Reentrant calls from the same thread must be allowed to proceed without # triggering the load again. # exec_module() and self-referential imports are the primary ways this can # happen, but in any case we must return something to avoid deadlock. if loader_state['is_loading']: - return object.__getattribute__(self, attr) + return __class__.__getattribute__(self, attr) loader_state['is_loading'] = True - __dict__ = object.__getattribute__(self, '__dict__') + __dict__ = __class__.__getattribute__(self, '__dict__') # All module metadata must be gathered from __spec__ in order to avoid # using mutated values. @@ -216,8 +218,10 @@ def __getattribute__(self, attr): # Update after loading since that's what would happen in an eager # loading situation. __dict__.update(attrs_updated) - # Finally, stop triggering this method. - self.__class__ = types.ModuleType + # Finally, stop triggering this method, if the module did not + # already update its own __class__. + if isinstance(self, _LazyModule): + object.__setattr__(self, '__class__', __class__) return getattr(self, attr)