Added decorator signature transfer to AdaptedDecorator meta-decorator…

… class

polymerist/genutils/decorators/meta.py

@@ -1,7 +1,7 @@
 '''Decorators for modifying other decorators'''
 
 from typing import Concatenate, Callable, ParamSpec, TypeAlias, TypeVar
-from functools import update_wrapper
+from functools import update_wrapper, wraps
 
 from ..typetools.parametric import C, O, P, R, Args, KWArgs
 Decorator : TypeAlias = Callable[[Callable[P, R]], Callable[P, R]]
@@ -11,16 +11,16 @@
 def extend_to_methods(dec : Decorator) -> Decorator:
     '''Meta-decorator; modifies an existing decorator definition to be transferrable to methods with no additional code
     The modified decorator can be used interchangably to decorate both ordinary functions AND methods of classes'''
-    class AdaptedDecorator:
-        __doc__ = dec.__doc__ # copy docstring for annotation
+    ReturnSignature = dec.__annotations__.get('return')
 
+    @wraps(dec, updated=()) # transfer decorator signature to decorator adapter class, without updating the __dict__ field
+    class AdaptedDecorator:
         def __init__(self, funct : Callable[P, R]) -> None:
             '''Record function'''
             self.funct = funct
             update_wrapper(self, funct) # equivalent to functools.wraps, transfers docstring, module, etc. for documentation
-            # TODO : figure out how to transfer decorator signature updates to this level
 
-        def __call__(self, *args : Args, **kwargs : KWArgs) -> dec.__annotations__.get('return'): # TODO : fix this to reflect the decorator's return signature
+        def __call__(self, *args : Args, **kwargs : KWArgs) -> ReturnSignature: # TODO : fix this to reflect the decorator's return signature
             '''Apply decorator to function, then call decorated function'''
             return dec(self.funct)(*args, **kwargs)