LACE-626 | Try to run tests using Python 3.9

[macbre]

See https://github.com/bethinkpl/chronos/pull/119

[macbre]

nox > poetry run pylint src tests noxfile.py cli.py
************* Module src.pythink_toolbox.validating
src/pythink_toolbox/validating.py:59:30: E1136: Value 'Optional' is unsubscriptable (unsubscriptable-object)
src/pythink_toolbox/validating.py:110:10: E1136: Value 'Optional' is unsubscriptable (unsubscriptable-object)
************* Module src.pythink_toolbox.testing.parametrization
src/pythink_toolbox/testing/parametrization.py:7:0: E0239: Inheriting 'TypedDict', which is not a class. (inherit-non-class)
src/pythink_toolbox/testing/parametrization.py:7:0: R0903: Too few public methods (0/2) (too-few-public-methods)
src/pythink_toolbox/testing/parametrization.py:19:25: E1136: Value 'Union' is unsubscriptable (unsubscriptable-object)
src/pythink_toolbox/testing/parametrization.py:24:20: E1136: Value 'Union' is unsubscriptable (unsubscriptable-object)
************* Module tests.test_validating
tests/test_validating.py:14:12: E1136: Value 'Optional' is unsubscriptable (unsubscriptable-object)
tests/test_validating.py:17:15: E1136: Value 'Optional' is unsubscriptable (unsubscriptable-object)
tests/test_validating.py:12:0: R0903: Too few public methods (0/2) (too-few-public-methods)
tests/test_validating.py:75:12: E1136: Value 'Optional' is unsubscriptable (unsubscriptable-object)
tests/test_validating.py:78:15: E1136: Value 'Optional' is unsubscriptable (unsubscriptable-object)
tests/test_validating.py:91:0: R0903: Too few public methods (0/2) (too-few-public-methods)
tests/test_validating.py:132:0: R0903: Too few public methods (0/2) (too-few-public-methods)
************* Module tests.test_testing.test_paramatrization
tests/test_testing/test_paramatrization.py:9:0: R0903: Too few public methods (0/2) (too-few-public-methods)

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Your code has been rated at 7.06/10

http://pylint-messages.wikidot.com/messages:e1136 + pylint-dev/pylint#3882 (seems to be blocked on pylint-dev/pylint#3890 which has not yet been released)

[miloszbednarzak]

@macbre by default we check python 3.9, but we don't require it to pass yet. We just check it to be sure if we are ready to switch to 3.9. But if we want to use 3.9 in Chronos we need pythink-toolbox to pass 3.9 checks also.

[macbre]

The latest Pylint 2.6.0 still does not support Python 3.9 -> pylint-dev/pylint@2a86092 is still in master.

The question is - do we want to wait for Pylint with Python 3.9 to be released or do we simply ignore pylint warnings in Python 3.9 build for now and tag a new version of pythink-toolbox? @miloszbednarzak ?

[miloszbednarzak]

@macbre I'd rather wait than ignore pylint. Pylint is our guardian angel, so I want to bet on it.
Also maintainers "promised" that release will be soon: pylint-dev/pylint#3882 (comment)

[macbre]

https://github.com/PyCQA/pylint/milestone/24 - pylint's 2.6.1 milestone is only 41% complete now. We have to wait...

[macbre]

nox > poetry run pylint src tests noxfile.py cli.py
************* Module src.pythink_toolbox.testing.parametrization
src/pythink_toolbox/testing/parametrization.py:7:0: R0903: Too few public methods (0/2) (too-few-public-methods)
************* Module tests.test_validating
tests/test_validating.py:12:0: R0903: Too few public methods (0/2) (too-few-public-methods)
tests/test_validating.py:91:0: R0903: Too few public methods (0/2) (too-few-public-methods)
tests/test_validating.py:132:0: R0903: Too few public methods (0/2) (too-few-public-methods)
************* Module tests.test_testing.test_paramatrization
tests/test_testing/test_paramatrization.py:9:0: R0903: Too few public methods (0/2) (too-few-public-methods)