Defining a module foo results in foo.foo being available

[not-my-profile]

Run maturin new -b pyo3 foo, followed by maturin dev in a venv.

>>> import foo
>>> foo.foo
<module 'foo.foo' from '/tmp/venv/lib/python3.9/site-packages/foo/foo.cpython-39-x86_64-linux-gnu.so'>

I would expect foo.foo to be undefined. The same can be observed when using rust-cpython.

Versions:

• maturin 0.14.8
• Python 3.9.2
• pip 20.3.4

[messense]

It is by design, see also #1365

[not-my-profile]

What is the reasoning behind this design decision? (Sidenote: If the .so file is part of the package I think prefixing its name with an _ would be somewhat better since it would clarify that it's not part of the public API.)

For my project I would prefer the .so file to reside directly in site-packages/ to avoid having any modules that you can import but actually should not import.

[messense]

See #558, it allows package type stubs automatically.

Sidenote: If the .so file is part of the package I think prefixing its name with an _ would be somewhat better since it would clarify that it's not part of the public API.

You can use mixed layout to do this, see https://www.maturin.rs/project_layout.html#import-rust-as-a-submodule-of-your-project

[not-my-profile]

See #558, it allows package type stubs automatically.

I don't see anything about putting the .so file directly in site-packages that would prevent type stubs from being packaged. The following works just fine (tested with pyright):

site-packages
├── my_project.cpython-36m-x86_64-linux-gnu.so
├── my_project.pyi
└── my_project-2.1.2.dist-info
    └── ...

(Putting my_project/__init__.pyi in site-packages also works).

[messense]

That would miss the py.typed marker I think? Does it work with every other IDEs? I'm not sure.

[not-my-profile]

Ah yes of course, you're correct that this wouldn't work with py.typed. Thanks!

I just opened python/typing#1333 about introducing some way to mark .so files as typed without having to introduce an intermediary __init__.py file :)