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bpo-35917: Test multiprocessing manager classes and shareable types by giampaolo · Pull Request #11772 · python/cpython

@giampaolo I think you misunderstood the test failures. A RLock can only be released by the thread/process which acquired it. Example:

>>> import threading                                                                      
>>> lock = threading.RLock()                                                              
>>> lock.acquire()                                                                        
True
>>> t = threading.Thread(target=lock.release)                                             
>>> t.start()                                                                             
Exception in thread Thread-1990:
Traceback (most recent call last):
  File "/home/antoine/miniconda3/envs/pyarrow/lib/python3.7/threading.py", line 917, in _bootstrap_inner
    self.run()
  File "/home/antoine/miniconda3/envs/pyarrow/lib/python3.7/threading.py", line 865, in run
    self._target(*self._args, **self._kwargs)
RuntimeError: cannot release un-acquired lock

Same with multiprocessing:

>>> lock = mp.RLock()                                                                     
>>> lock.acquire()                                                                        
True
>>> proc = mp.Process(target=lock.release)                                                
>>> proc.start()                                                                          
Process Process-1:
>>> Traceback (most recent call last):                                                    
  File "/home/antoine/miniconda3/envs/pyarrow/lib/python3.7/multiprocessing/process.py", line 297, in _bootstrap
    self.run()
  File "/home/antoine/miniconda3/envs/pyarrow/lib/python3.7/multiprocessing/process.py", line 99, in run
    self._target(*self._args, **self._kwargs)
AssertionError: attempt to release recursive lock not owned by thread

So you should write the RLock and Condition tests differently.