Option to set fallback working directory to nearest pyproject.toml dir

[avdstaaij]

Consider the following circumstances:

• The Python file that is being edited is in a "Python project directory" (a directory with a pyproject.toml).
• The Python project directory does not include Ruff configuration; user-wide Ruff configuration is active instead.
• The Python project directory is not the VS Code workspace root.

Visualization:

VS Code workspace root
└── Python project
    ├── src
    │   └── file_being_edited.py
    └── pyproject.toml

In these circumstances, it appears that the extension runs Ruff with the VS Code workspace root as the working directory. This has some negative effects on a few linter rules that may be enabled in the user-wide configuration. The ones I've noticed:

• FA, UP: These rules rely on the inferred Python version. Although a Python version may be specified in the project's pyproject.toml, Ruff won't detect it, and will instead fall back on the user-wide configuration. (If I understand https://docs.astral.sh/ruff/configuration/#inferring-the-python-version correctly, this is the expected behavior when Ruff's working directory is set to the VS Code root.)

• I001: First-party imports may not be detected correctly, leading to different formatting of the import list.

It would be nice if there was an option to make the extension set Ruff's working directory to the "nearest" python project directory instead, so that these linting rules work better when using user-wide Ruff configuration.

For example, the Mypy extension (ms-python.mypy-type-checker) has a setting mypy-type-checker.cwd which can be set to ${nearestConfig} to achieve this behavior.

(If there's already a way to make the rules I mentioned work in this situation, I'd love to hear it!)

[dhruvmanila]

Hi, thank you for the report.

Can I ask why are you opening VS Code in an outer directory instead of in the project root? Are you using multi-root workspaces i.e., opening multiple projects in a single instance of VS Code?

For example, the Mypy extension (ms-python.mypy-type-checker) has a setting mypy-type-checker.cwd which can be set to ${nearestConfig} to achieve this behavior.

That's interesting. No, Ruff doesn't have that option and I don't know if that'll work in our case. This is because Ruff's extension uses the Ruff language server to power these features in an editor while mypy uses the mypy command-line tool to power those features. We'll have to change it at the server level which will could require a different solution.

[avdstaaij]

Thanks for taking a look at this!

Can I ask why are you opening VS Code in an outer directory instead of in the project root? Are you using multi-root workspaces i.e., opening multiple projects in a single instance of VS Code?

No, I'm not using multi-root workspaces, though I imagine this might affect those too.

I'm encountering this when working on projects that are not primarily written in Python, but which contain some custom Python-written tools in a subdirectory. I prefer to open the main project root / git root in VS Code in these cases, since I frequently go back and forth between editing the Python code and the main project code. I do realize that this is probably a pretty niche use case, though.

Another situation where I can imagine this coming up, is when managing multiple Python projects in a monorepo.