Dill can't pickle abstractproperty, abstractclassmethod, or abstractstaticmethod objects

[alimuldal]

The following:

import abc
import dill

print(dill.__version__)  # 0.3.1.1

class FooBar(abc.ABC):

    @abc.abstractproperty
    def thingy(self):
        return 42


dill.dumps(FooBar)

fails with:

---------------------------------------------------------------------------                                                                                                                                         
TypeError                                 Traceback (most recent call last)                                                                                                                                         
<ipython-input-4-ad16237f3136> in <module>                                                                                                                                                                          
----> 1 dill.dumps(FooBar)                                                                                                                                                                                          
                                                                                                                                                                                                                    
~/.venvs/dill/lib/python3.7/site-packages/dill/_dill.py in dumps(obj, protocol, byref, fmode, recurse, **kwds)                                                                                                      
    263     """pickle an object to a string"""                                                                                                                                                                      
    264     file = StringIO()                                                                                                                                                                                       
--> 265     dump(obj, file, protocol, byref, fmode, recurse, **kwds)#, strictio)                                                                                                                                    
    266     return file.getvalue()                                                                                                                                                                                  
    267                                                                                                                                                                                                             
                                                                                                                                                                                                                    
~/.venvs/dill/lib/python3.7/site-packages/dill/_dill.py in dump(obj, file, protocol, byref, fmode, recurse, **kwds)                                                                                                 
    257     _kwds = kwds.copy()                                                                                                                                                                                     
    258     _kwds.update(dict(byref=byref, fmode=fmode, recurse=recurse))                                                                                                                                           
--> 259     Pickler(file, protocol, **_kwds).dump(obj)                                                                                                                                                              
    260     return                                                                                                                                                                                                  
    261                                                                                                                                                                                                             
                                                                                                                                                                                                                    
~/.venvs/dill/lib/python3.7/site-packages/dill/_dill.py in dump(self, obj)                                                                                                                                          
    443             raise PicklingError(msg)                                                                                                                                                                        
    444         else:                                                                                                                                                                                               
--> 445             StockPickler.dump(self, obj)                                                                                                                                                                    
    446         stack.clear()  # clear record of 'recursion-sensitive' pickled objects                                                                                                                              
    447         return                                                                                                                                                                                              
                                                                                                                                                                                                                    
/usr/lib/python3.7/pickle.py in dump(self, obj)                                                                                                                                                                     
    435         if self.proto >= 4:                                                                                                                                                                                 
    436             self.framer.start_framing()                                                                                                                                                                     
--> 437         self.save(obj)                                                                                                                                                                                      
    438         self.write(STOP)                                                                                                                                                                                    
    439         self.framer.end_framing()                                                                                                                                                                           
                                                                                                                                                                                                                    
/usr/lib/python3.7/pickle.py in save(self, obj, save_persistent_id)                                                                                                                                                 
    502         f = self.dispatch.get(t)                                                                                                                                                                            
    503         if f is not None:                                                                                                                                                                                   
--> 504             f(self, obj) # Call unbound method with explicit self                                                                                                                                           
    505             return                                                                                                                                                                                          
    506                                                                                                                                                                                                             
                                                                                                                                                                                                                    
~/.venvs/dill/lib/python3.7/site-packages/dill/_dill.py in save_type(pickler, obj)                                                                                                                                  
   1339             del _dict[name]                                                                                                                                                                                 
   1340         pickler.save_reduce(_create_type, (type(obj), obj.__name__,
-> 1341                                            obj.__bases__, _dict), obj=obj)
   1342         log.info("# %s" % _t)
   1343     # special cases: NoneType

/usr/lib/python3.7/pickle.py in save_reduce(self, func, args, state, listitems, dictitems, obj)
    636         else:
    637             save(func)
--> 638             save(args)
    639             write(REDUCE)
    640 

/usr/lib/python3.7/pickle.py in save(self, obj, save_persistent_id)
    502         f = self.dispatch.get(t)
    503         if f is not None:
--> 504             f(self, obj) # Call unbound method with explicit self
    505             return
    506 

/usr/lib/python3.7/pickle.py in save_tuple(self, obj)
    787         write(MARK)
    788         for element in obj:
--> 789             save(element)
    790 
    791         if id(obj) in memo:

/usr/lib/python3.7/pickle.py in save(self, obj, save_persistent_id)
    502         f = self.dispatch.get(t)
    503         if f is not None:
--> 504             f(self, obj) # Call unbound method with explicit self
    505             return
    506 

~/.venvs/dill/lib/python3.7/site-packages/dill/_dill.py in save_module_dict(pickler, obj)
    910             # we only care about session the first pass thru
    911             pickler._session = False
--> 912         StockPickler.save_dict(pickler, obj)
    913         log.info("# D2")
    914     return

/usr/lib/python3.7/pickle.py in save_dict(self, obj)
    857 
    858         self.memoize(obj)
--> 859         self._batch_setitems(obj.items())
    860 
    861     dispatch[dict] = save_dict

/usr/lib/python3.7/pickle.py in _batch_setitems(self, items)
    883                 for k, v in tmp:
    884                     save(k)
--> 885                     save(v)
    886                 write(SETITEMS)
    887             elif n:

/usr/lib/python3.7/pickle.py in save(self, obj, save_persistent_id)
    522             reduce = getattr(obj, "__reduce_ex__", None)
    523             if reduce is not None:
--> 524                 rv = reduce(self.proto)
    525             else:
    526                 reduce = getattr(obj, "__reduce__", None)

TypeError: can't pickle abstractproperty objects

abstractclassmethod and abstractstaticmethod also fail in the same way.

[LarsHill]

Is probably related to #332

[mmckerns]

Python 3.8.17 (default, Jun 11 2023, 01:54:00) 
[Clang 13.1.6 (clang-1316.0.21.2.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import abc
>>> import dill
>>> class FooBar(abc.ABC):
...     @abc.abstractproperty
...     def thingy(self):
...         return 42
... 
>>> dill.dumps(FooBar)
b'\x80\x04\x95\x97\x01\x00\x00\x00\x00\x00\x00\x8c\ndill._dill\x94\x8c\x0c_create_type\x94\x93\x94(\x8c\x03abc\x94\x8c\x07ABCMeta\x94\x93\x94\x8c\x06FooBar\x94h\x03\x8c\x03ABC\x94\x93\x94\x85\x94}\x94(\x8c\n__module__\x94\x8c\x08__main__\x94\x8c\x06thingy\x94h\x03\x8c\x10abstractproperty\x94\x93\x94(h\x00\x8c\x10_create_function\x94\x93\x94(h\x00\x8c\x0c_create_code\x94\x93\x94(K\x01K\x00K\x00K\x01K\x01KCC\x04d\x01S\x00\x94NK*\x86\x94)\x8c\x04self\x94\x85\x94\x8c\x07<stdin>\x94h\rK\x02C\x02\x00\x02\x94))t\x94R\x94c__builtin__\n__main__\nh\rNNt\x94R\x94}\x94}\x94(\x8c\x0f__annotations__\x94}\x94\x8c\x0c__qualname__\x94\x8c\rFooBar.thingy\x94u\x86\x94bNNNt\x94R\x94\x8c\x07__doc__\x94N\x8c\x13__abstractmethods__\x94(h\r\x91\x94ut\x94R\x94\x8c\x08builtins\x94\x8c\x07setattr\x94\x93\x94h+h"h\x06\x87\x94R0.'
>>> dill.__version__
'0.3.8.dev0'

This now works. Closing.