How pytest resolves import

[michaelx1999]

Here is my folder structure

/root
  /app
    __init__.py
    /main.py
  /tests
    test_something.py (from app.main import ...)

When I run pytest inside /root or /root/tests, I get the error message "cannot import module app".

I change the folder structure to this and everything works fine.

/root
  /app
    __init__.py
    /main.py
  /tests
    __init__.py
    test_something.py (from app.main import ...)

1. How does adding this init file under tests resolves import error
2. How come pytest are able to resolves import correctly when I'm inside different directories? (/root, /root/tests)

[wimglenn]

I answered the same question already on stackoverflow, here:
https://stackoverflow.com/a/72368703/674039

[markshao]

you should run under root,otherwise add roo
t to pythonpath