While working on refreshing my cookiecutter-pyproject repository, I ran into a ModuleNotFoundError when running my tests with uv run pytest. My project directory looks like this:
my-project/
├─ docs/
├─ src/
│ └── my_project/
│ ├─ __init__.py
│ └─ main.py
├─ tests/
│ ├─ __init__.py
│ └─ test_my_project.py
├─ pyproject.toml
└─ README.md
and the contents of test_my_project.py look like this:
"""Tests for my_project package."""
import my_project
def test_version():
"""Verify the package version."""
assert my_project.__version__ == "0.1.0"
My suspicion was that the src directory wasn’t being searched and imported by pytest, even though both my module and my test directory had __init__.py files.
After looking at the pytest docs explanation as to how pytest imports files, the fix I went with was to set the pythonpath value in my pyproject.toml file like so:
[tool.pytest.ini_options]
pythonpath = [
"src"
]
After that, re-running uv run pytest from my project’s root directory was successful!