Using pytest where test in subfolder

Question

I'm using python pytest to run my unit tests. My project folders are:

Main - contains data file: A.txt

Main\Tests - the folder from which I run pytest

Main\Tests\A_test - folder that contains a test file

The test in A_test folder uses the file A.txt (that is in Main folder).

My problem is that when I run py.test the test fails because it can't find A.txt.

I found out that it is because pytest uses the path Main\Test when running the test instead of changing the path to Main\Tests\A_test (I'm using relative path when opening A.txt inside the test file)

My question: is there a way to make pytest change directory to the folder of the test it executes for each test? so that relative paths inside the tests will still work?

Is there some other generic way to solve it? (I don't want to change everything to absolute paths or something like this, also this is an example, in real life I have several hundreds tests).

Thank you,

Noam

Answer 1

Assuming you need your root Main in the sys.path.

Giving your current dir is Main/:

$python -m pytest Tests/A_test

This will append Main to the sys.path and run tests in the A_test subdirectory. More about pythonpath and pytest relationship here: http://doc.pytest.org/en/latest/pythonpath.html#pythonpath

Answer 2

I think the "truest" answer (perhaps subject to opinion) comes from the pytest docs themselves: the testpaths configuration option can be set in a setup.cfg, pytest.ini, tox.ini, or pyroject.toml file.