Bug Description

Because of some aspects of how sources work in our dev build, I wanted to do something along the lines of the following:

maturin develop --config 'tool.maturin.python-source="rerun_sdk"' --manifest-path rerun_py/Cargo.toml

There's a config parser that's validating that it's proper dotted key=val notation, but none of the values I put there seem to make a difference.

Your maturin version (maturin --version)

1.5.1

Your Python version (python -V)

3.11.8

Your pip version (pip -V)

23.2.1

What bindings you're using

pyo3

Does cargo build work?

• Yes, it works

If on windows, have you checked that you aren't accidentally using unix path (those with the forward slash /)?

• Yes

Steps to Reproduce

Try building a package and overriding python-source.