[CG-10889] fix: Nested package

[tomcodgen]

Motivation

Content

Testing

Please check the following before marking your PR as ready for review

• I have added tests for my changes
• I have updated the documentation or added new documentation as needed

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

✅ All tests successful. No failed tests found.

Additional details and impacted files

[codegen-team]

Overall, this is a solid improvement to the import resolution system. The changes are focused and the test coverage demonstrates the functionality well. A few suggestions for consideration:

1. Documentation: Consider adding a comment explaining the purpose of the new fallback path (see inline comment)
2. Test Coverage: Adding a negative test case would help ensure the exclusion logic works as intended (see inline comment)
3. Performance: The current implementation creates a new string for each split operation. While likely not a performance bottleneck, consider using module_source.partition(".") if you only need the first component.

The changes look good to merge after addressing the documentation suggestion. The test coverage suggestion would be a nice-to-have but isn't blocking.

[bagel897]

TLDR

Hmm I feel like this entails us supporting reading pyproject.toml the way we do with tsconfig.json?
IMO #601 is a better approach for that than us hacking it together?

Full comment

For context, python supports resolving imports the following way:

1. You get a list of paths that comprise PYTHONPATH/sys.path. This generally includes the project root/cwd (as "")
2. For each path, we do to resolve this import in a given path

We have some implementations for 1:

1. base_path (our current method to override this manually)
2. src/test detection (which I believe is standard for packages?)

For this case, we can

1. Add hacks for individual cases like this PR
2. Support reading sys.path/PYTHONPATH (Allow custom overrites for package resolving and optional sys.path support #601, my preference)
3. Set the base_path as needed (current solution)

Thoughts?

hold on

[tomcodgen]

addressed in #601