[BUG] Error raising while running the tests right after installation

[IgSMS]

Describe the bug After installing pygmo via conda installer I executed the command pygmo.test.run_test_suite(), however, the installation seems to have failed due to some errors arising as outputs. I installed pygmo in a new environment with Python 3.9.12 only. Afterwards, I installed Spyder to use as the IDE.

Three tests are failing due to the exact same error: NotImplementedError: pool objects cannot be passed between processes or pickled, found on .. \lib\multiprocessing\pool.py.

I have uninstalled and installed again, as well as updating, but the same errors keep appearing.

On the other hand, another error is found on test ´pygmo.test.decorator_problem_test_case´, being the error: AttributeError: 'NoneType' object has no attribute 'dv_log'.

To Reproduce Steps to reproduce the behavior:

1. Create a new Anaconda environment with Python 3.9.12.
2. Write on CMD prompt: conda install pygmo.
3. Install Spyder IDE.
4. Write on command window: import pygmo, pygmo.test.run_test_suite()
5. See errors

Expected behavior I expected to see no errors since I followed installation steps and checked whether the dependencies where also installed.

Environment (please complete the following information):

• OS: Windows-64
• Installation method: conda
• Conda version: 4.12.0
• Conda-build version: 3.21.8
• Python version: 3.9.12.final.0

[darioizzo]

Is this related to #116? Maybe you can try to run with that dill version and see if it fixes the problem. I think this will anyway be solved in the next (upcoming) release.

[IgSMS]

Okay, I will try running it with a different dill version. Also, do you think the AttributeError is related to the previous errors, or its nature is different?

[IgSMS]

Using Dill's version 0.3.5.1 actually worked! Thank you very much for your help.