Is Pants able to infer dependancies between python test files? I have the structure like this:

src

|_ python

|_ package

tests

|_python

|_package

- test_1.py

- test_2.py

- BUILD

With a import in test_2.py like

from test_1 import function

However the test fails this import unless I explicitly provide python_tests the source for

tests/python/package

.

python_tests(name=“tests”, sources=[“tests/python/package”])

Strangely while the above works, it gives a Unmatched glob warning ([WARN] Unmatched glob from tests/python/package:tests’s

sources

field: “tests/python/package/tests/python/package”

I think you need to define a

python_test_utils

and then make that as dependency

Thanks @refined-addition-53644 An explicit dependancy on

python_tests

back to itself (

tests/python/package:tests

) did the trick. Imports now work, and no more warnings. python_test_utils looks more like it would be more appropriate for test utility files such as stub files (*.pyi) and conftest.py than actual test files.

👋 Howdy! OK a few things here 😅 The

sources

field defines which files the generator target should use for generating targets (It's also relative to the build dir). So

sources=["tests/python/package"]

is saying there is one Python file named

tests/python/package

. Then it warns because there is no file at that path. Usually you don't need to change it, as the default https://www.pantsbuild.org/docs/reference-python_tests#codesourcescode is usually correct

Yeah I think Pants should be able to infer this dep, so I am curious why it isn't, but importing from another test is not a common pattern. Is

function

an actual test function or a helper function?

It’s a helper function. I’ve got another problem that might be related. The code being tested is in a regular package structure (has a init.py). The test code is just a bunch of modules. If I make it a regular package by dropping in a init.py into the directory it breaks the imports of actual code.

src

|_ python

|_ package

|_file_3.py

- init.py

tests

|_python

|_package

- test_1.py

- test_2.py

- BUILD

test_1.py contains a wrapper around a function imported

from package.file_3

in test_2.py I’m trying to import that wrapper

So generally we'd recommend breaking a reusable helper function out into its own file, which is owned by a

python_test_utils

target, rather than have it be owned by a

python_tests

, since you're not using it as a test itself

I thought that might be the case, thanks for confirming!