Hook uses *wrong* maturin executable

[jeertmans]

Bug Description

Hi!
I recently changed to an older machine and noticed that my code would not compile with the hook:

Uninstalled 1 package in 0.19ms
Installed 1 package in 0.43ms
failed to resolve project "/export/home/eertmans/repositories/DiffeRT/DiffeRT": pyproject.toml is invalid (does not have required fields)
building "differt_core"
maturin_import_hook [ERROR] command "/export/home/eertmans/.local/bin/maturin develop --manifest-path /export/home/eertmans/repositories/DiffeRT/DiffeRT/differt-core/Cargo.toml --color always --uv" returned non-zero exit status: 2
maturin_import_hook [ERROR] maturin output:
error: unexpected argument '--uv' found

  tip: to pass '--uv' as a value, use '-- --uv'

Usage: maturin develop <--quiet|--jobs <N>|--profile <PROFILE-NAME>|--features <FEATURES>|--all-features|--no-default-features|--target <TRIPLE>|--target-dir <DIRECTORY>|--manifest-path <PATH>|--ignore-rust-version|--verbose...|--color <WHEN>|--frozen|--locked|--offline|--config <KEY=VALUE>|-Z <FLAG>|--timings=<FMTS>|--future-incompat-report|ARGS>

For more information, try '--help'.

ImportError while loading conftest '/export/home/eertmans/repositories/DiffeRT/DiffeRT/differt/src/differt/conftest.py'.
differt/src/differt/__init__.py:3: in <module>
    from ._version import VERSION
differt/src/differt/_version.py:1: in <module>
    from differt_core import __version__  # Re-export version from code module
.venv/lib/python3.11/site-packages/maturin_import_hook/project_importer.py:151: in find_spec
    spec, rebuilt = self._rebuild_project(package_name, project_dir)
.venv/lib/python3.11/site-packages/maturin_import_hook/project_importer.py:261: in _rebuild_project
    maturin_output = develop_build_project(self.find_maturin(), resolved.cargo_manifest_path, settings)
.venv/lib/python3.11/site-packages/maturin_import_hook/_building.py:181: in develop_build_project
    raise MaturinError(msg)
E   maturin_import_hook.error.MaturinError: Failed to build package with maturin

I know --uv option was added as of maturin>=1.6, but this constraint is already specified in my pyproject.toml:

[build-system]
build-backend = "maturin"
requires = ["maturin>=1.6,<2"]

So I checked and, indeed, my global maturin executable was too old:

$ maturin --version   
maturin 1.5.1

and upgrading it to >=1.6 now works.

Is there a way for this hook to use the same maturin executable as the one from the build backend? I guess this can be hard, especially as the place where the build dependencies are installed is probably not obvious.

Otherwise, I think it could be nice to include some words about this in the docs.

What do you think?

Steps to Reproduce

1. Create dummy repo that uses uv;
2. Specify the build dependencies as above;
3. Install hook with --detect-uv;
4. Install maturin<1.6 globally;
5. Trigger the hook.

Please provide the output of python -m maturin_import_hook version (or provide manually)

OS: Linux-6.8.0-51-generic-x86_64-with-glibc2.39
Python: CPython 3.11.10
maturin-import-hook: 0.2.0
maturin: maturin 1.8.1
rustc: rustc 1.83.0 (90b35a623 2024-11-26)
pip: ?

Does maturin develop work when run manually for your project?

• Yes/No (leave blank if not applicable)

[mbway]

I think the build backend gets downloaded automatically by the installer so it's not persistent on your system. I suppose the import hook could also do this as an option

[davidhewitt]

Passing thought: an easier first step might be for the hook to warn (or error?) if the maturin version on the path doesn't match the requested one in the pyproject.toml.

[jeertmans]

I think the build backend gets downloaded automatically by the installer so it's not persistent on your system. I suppose the import hook could also do this as an option

Yes, this is what I thought when saying that it might not be obvious.

[jeertmans]

Passing thought: an easier first step might be for the hook to warn (or error?) if the maturin version on the path doesn't match the requested one in the pyproject.toml.

I think this would be a great addition!