changes to Cargo easyblock break installation of polars

[boegel]

The installation of polars-0.20.2-gfbf-2023a.eb is failing with current develop (and when using eb --ignore-checksums) with:

== 2025-01-25 19:43:23,905 build_log.py:171 ERROR EasyBuild crashed with an error (at easybuild/base/exceptions.py:126 in __init__): cmd " /software/Python/3.11.3-GCCcore-12.3.0/bin/python -m pip install --prefix=/software/polars/0.20.2-gfbf-2023a  --verbose  --no-deps  --ignore-installed  --no-index  --no-build-isolation  .[deltalake,matplotlib,numpy,openpyxl,pandas,pyarrow]" exited with exit code 1 and output:
Using pip 23.1.2 from /software/Python/3.11.3-GCCcore-12.3.0/lib/python3.11/site-packages/pip (python 3.11)
Processing /tmp/easybuild/polars/0.20.2/gfbf-2023a/polars-0.20.2
  Preparing metadata (pyproject.toml): started
  Running command Preparing metadata (pyproject.toml)
  error: failed to get `jsonpath_lib` as a dependency of package `polars-ops v0.35.4 (/tmp/easybuild/polars/0.20.2/gfbf-2023a/polars-0.20.2/crates/polars-ops)`

  Caused by:
    failed to load source for dependency `jsonpath_lib`

  Caused by:
    Unable to update https://github.com/ritchie46/jsonpath?branch=improve_compiled#24eaf0b4

  Caused by:
    can't checkout from 'https://github.com/ritchie46/jsonpath': you are in the offline mode (--offline)
   maturin failed
    Caused by: Cargo metadata failed. Does your crate compile with `cargo build`?
    Caused by: `cargo metadata` exited with an error:
  Error running maturin: Command '['maturin', 'pep517', 'write-dist-info', '--metadata-directory', '/tmp/eb-p76aywjz/pip-modern-metadata-5wesklv0', '--interpreter', '/software/Python/3.11.3-GCCcore-12.3.0/bin/python']' returned non-zero exit status 1.
  Checking for Rust toolchain....
  Running `maturin pep517 write-dist-info --metadata-directory /tmp/eb-p76aywjz/pip-modern-metadata-5wesklv0 --interpreter /software/Python/3.11.3-GCCcore-12.3.0/bin/python`  error: subprocess-exited-with-error

To get to this point, I had to first remove the checksums list from the polars easyconfig, otherwise I hit an earlier error:

== FAILED: Installation ended unsuccessfully (build directory: /tmp/vsc40003/easybuild/polars/0.20.2/gfbf-2023a): build failed (first 300 chars): Missing checksum for
jsonpath_lib-0.3.0-24eaf0b4416edff38a4d1b6b17bc4b9f3f047b4b.tar.gz in {'jsonpath_lib-0.3.0.tar.gz': 'dfb5eb7f47b5b5a7b35262f7b41787a785958001a23ff039cdae926396c6af96'}

It seems like this problem was introduced in #3483, which changed how crates entries that use a Git repo, as is the case for jsonpath_lib in the polars easyconfig:

crates = [
    ...
    ('jsonpath_lib', '0.3.0', 'https://github.com/ritchie46/jsonpath', '24eaf0b4416edff38a4d1b6b17bc4b9f3f047b4b'),

One key difference seems to be the name of the source file: in the working installation it's jsonpath_lib-0.3.0.tar.gz, while with current develop I'm seeing jsonpath_lib-0.3.0-24eaf0b4416edff38a4d1b6b17bc4b9f3f047b4b.tar.gz being used.

After unpacking, these tarballs are exactly the same though.
And while jsonpath_lib-0.3.0-24eaf0b4416edff38a4d1b6b17bc4b9f3f047b4b.tar.gz is being unpacked to /tmp/easybuild/polars/0.20.2/gfbf-2023a/easybuild_vendor_git/jsonpath, it gets moved to /tmp/easybuild/polars/0.20.2/gfbf-2023a/easybuild_vendor/jsonpath, which is the same path that jsonpath_lib-0.3.0.tar.gz gets unpacked into in the working installation.
So I'm not entirely sure what actually causes the " failed to load source for dependency" problem...

@Micket Any ideas here?