Maturin does not show any output when cargo build is blocked

[datapythonista]

Bug Description

When running maturin build or maturin develop, maturin doesn't show any output, but doesn't do anything. After starting to fill this issue, and testing cargo build, I realized something was wrong with my cargo, which was blocked and reporting Blocking waiting for file lock on the registry index.

Not sure how it'd affect other use cases, but seems from this that it'd be a good idea to redirect the output of cargo build to maturin, otherwise it's quite difficult to guess what's going on if cargo build has an issue like in this case.

Your Python version (python -V)

Python 3.11.0

Your pip version (pip -V)

pip 22.3 from /home/mgarcia/.mambaforge/envs/data/lib/python3.11/site-packages/pip (python 3.11)

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

1. Have cargo with a lock (e.g. touch ~/.cargo/.package-cache)
2. Create new project with maturin init
3. Run maturin develop

[messense]

There is not much maturin can do at the moment, it's blocking on https://docs.rs/cargo_metadata/latest/cargo_metadata/struct.MetadataCommand.html#method.exec, that crate does not provide a way to show output.

[datapythonista]

Thanks for letting me know, I opened oli-obk/cargo_metadata#210 for it.

[messense]

I've sent a patch in oli-obk/cargo_metadata#211