Hey all, I am having a problem testing one of my python modules because it can't seem to find one of my internal dependencies that is in the test folder. Here is my project structure:

└── src
    ├── python
    │   ├── platform_hardware
    │   │   ├── folder1
    │   │   ├── folder2
    │   │   ├── tests
    │   │   |   ├── BUILD
    │   │   |   ├── test_file1.py
    │   │   |   ├── test_file2.py
    │   │   |   └── mock_interface.py
    │   │   ├── __main__.py
    │   │   └── BUILD

Here is the BUILD file in my tests directory:

python_test_utils(
    name="test_utils",
    sources=["mock_interface.py"]
)

python_tests(
    name="tests",
    dependencies=[":test_utils"]
)

Both of my test files import from the mock_interfact.py file, and that import looks like this:

from tests.mock_interface import MockInterface

When I try to run my tests using

pants test src/python/platform_hardware/tests:

I get the following error:

from tests.mock_interface import MockInterface
E   ModuleNotFoundError: No module named 'tests'

I feel like there is a really simple solution here that I'm missing, but I've been pulling my hair out for hours trying to get these tests to run. I've tried using fully qualified names in the BUILD file, I've tried creating the target for this file as both a file or python source, and I've tried importing this file in all the ways that make sense to me. What am I missing/doing wrong here?

tests

isn’t a package so I don’t think you can import from it like that. Try adding a

___init___.py

file inside the

tests

directory and see if that works?

Sorry, I didn't include that for brevity, but there is an init.py in the tests folder

Is there one in

platform_hardware

?

Yes

Got it. You should be able to inspect the contents of the test sandbox by running:

pants --keep_sandboxes=on_failure test src/python/platform_hardware/tests::

Since it fails, the sandbox should be retained on local disk, and you can go to that folder and see what files are inside. I’m guessing something is not being added to the sandbox where it should be.

I'm not sure exactly what I'm looking for here, but yeah the mock_interface file isn't in here

Are the test files there / other source files?

The test file is there. As for the source files, there is only one source file. The source file that I'm seeing is imported by the test, but the source file also has imports of its own, and none of those are present.

I think it might be that the import path is incorrect, and you need to change:

from tests.mock_interface import MockInterface

to:

from platform_hardware.tests.mock_interface import MockInterface

That gives me the same error, ModuleNotFoundError: No module named 'platform_hardware.tests'

how are your source roots set up? Not sure exactly what the problem is, but my suspicion is that you need to set up your source roots so that the imports can be read correctly

pants source roots returns 'src/python'