Does pants project follow any Python style guide?

Sort of. It’s not very fleshed out. https://www.pantsbuild.org/styleguide.html

The last commit for the pylint was 7 years ago.

Good find! We do have a couple of other ways we enforce style by running

./pants fmt ::

, which for example calls isort. But I think there are opportunities to make the style more consistent, through a mix of more tooling like auto-formatters and expanding our style guide

I feel some of the codes are really hard to read. For instance, this part https://github.com/pantsbuild/pants/blob/272b0a5/src/python/pants/build_graph/build_file_parser.py#L74-L88 is too many level of nesting for such a simple function.

There are parts that I think we could probably incorporate! That’d be great.

+1 to all of that, plus the v2 engine allows flattening out deeply nested logic via dependency injection

“allows flattening out deeply nested logic via dependency injection” tbh, dependency injection sounds a bit scarier to me than deeply nested logic

in the native backend it's used so that the logic of creating a compiler and linker setup that works on every system is contained in

native_toolchain.py

and that is a massive win imho

I'm always weary of pylint, I prefer the softer defaults of flake8