Pants test using a different module version than it's assigned resolve

[enriquemaffezzini]

I have a test that depends on the packaging module. The resolve python_rasa has packaging<=21.3 in its requirements 3rdparty/requirements/python_rasa.txt and its lock-file "version": "20.9" for packaging.

The BUILD file in project's root folder overrides the resolve to python_rasa:

projects/chatbot/BUILD

__defaults__(
    {
        (python_sources, python_source, python_tests, pex_binaries, pex_binary): dict(
            resolve="python_rasa"
        )
    }
)
resource(name="pyproject", source="pyproject.toml")

As a redundancy, I also pointed out the resolve for the test despite the BUILD in the project's root folder should be enough:

projects/chatbot/tests/BUILD

python_tests(
    name="tests",
    resolve="python_rasa"
)

Finally, the current test file is currently just printing the packagingversion as pants run runs just fine and pants test fails due to a packaging version problem on the real test.

projects/chatbot/tests/test_packaging.py

import packaging
print("Packaging version:", packaging.__version__)
from rasa.shared.nlu.training_data.message import Message
def test_placebo():
    assert 1 == 1

pants test projects/chatbot/tests/:: prints Packaging version: 23.0 failing with ImportError: cannot import name 'LegacyVersion' from 'packaging.version'; class that is deprecated after packaging 21.3. The logs show that pants test builds 3rdparty/lockfiles/python_rasa.lock, which are the correct ones with packaging version 20.9.

Curiously enough, pants run projects/chatbot/tests/test_packaging.py prints Packaging version: 20.9 passing the test.

pants dependencies --transitive projects/chatbot/tests/test_packaging.pywould return:

3rdparty/lockfiles/python_rasa.lock:_python_rasa_lockfile
3rdparty/requirements/python_rasa.txt:../requirements_rasa
3rdparty:requirements_rasa#es-dep-news-trf
3rdparty:requirements_rasa#packaging
3rdparty:requirements_rasa#rasa
3rdparty:requirements_rasa#spacy

Any idea why is pants test is building packaging 23.0 instead of 20.9?

[benjyw]

pytest itself depends on packaging, so I suspect that is the issue. Are you installing pytest from a custom resolve?

If so, you can set the packaging version in that resolve's lockfile inputs.

One convenient way to do this is to add pytest to your python_rasa resolve (it may already be there because your tests probably import from it?) and then set:

[pytest]
install_from_resolve = "python_rasa"  
# Enumerate the requirements that pytest actually needs to run itself.
# If you don't it will use the entire lockfile, which means every lockfile change will invalidate all tests.
requirements =[...]  

[enriquemaffezzini]

You nailed it! Using install_from_resolve = "python_rasa" in the toml file does the trick.

Can you think of any way in which I can force this project tests to use the project's resolve pytest or to override the pytest resolve for such tests? I need to keep the rest of the projects with the same pytest setting. Specifying the resolve in the test folder build file like this is not having the expected effect:

projects/chatbot/tests/BUILD

python_tests(
    name="tests",
    resolve="python_rasa"
)

[benjyw]

Unfortunately that is not currently possible - the resolve that pytest runs from is set globally. However this is a much-requested feature in the New Python Backend discussions. Feel free to chime in there.

For now, probably best is to generate a custom pytest lockfile that pins packaging.

This is an unfortunate problem with pytest - it loads the code under test into the same namespace as its own code. Really, it should "shade" itself and its dependencies.

[enriquemaffezzini]

Thanks a lot for your guidance was very valuable. We got everything working following your advice

[benjyw]

Glad to hear it! Hopefully in the future this will be handled more smoothly.