I am working in a codebase with the following folder structure:

lambdas
|-lambda1
  |-core
  |-infrastructure
  ...
|-lambda2
  |-core
  |-infrastructure
  ...
...
tests
|-unit
  |-lambda1
    ...tests
  |-lambda2
    ...tests
  ...

Since the lambdas are all deployed independently, imports within each lambda are absolute and from the root, like so:

import core.domain.user

My issue arises when I am running tests with PyTest. When the tests for lambda1 are ran, sys.modules creates an entry for ‘core’ and maps it to the core module in lambda1:

{
...
'core': <module 'core' from '/Users/me/project/lambdas/lambda1/core/__init__.py'>
...
}

Then, when I want to import ‘core’ again when the lambda2 tests run, I get errors since the wrong core module is imported.

I have tried deleting this entry in conftest.py but that didn’t solve the issue, I think since sys.path will also grab the wrong ‘core’ module depending on its order. I have tried altering sys.path in every test file and that seems to help but feels too much like a hack.

I think that moving the tests to be in the same directory as their lambda would help, but I want to explore options that don’t alter the folder structure first.

Any ideas?