Updated package.py for singularity-eos to avoid spack.* constructs

[leowerneck]

PR Summary

I ran the following commands to install singularity-eos on macOS and Linux, but encountered an error:

cd
git clone https://github.com/spack/spack.git
source ~/spack/share/spack/setup-env.sh
spack compiler find
spack external find --not-buildable
git clone --recursive [email protected]:lanl/singularity-eos.git
spack repo add singularity-eos/spack-repo
spack install singularity-eos
==> Error: cannot load package 'singularity-eos' from the 'singularity_eos' repository: name 'spack' is not defined

After researching online a bit, the problem seems to boil down to this offending line in spack-repo/packages/singularity-eos/package.py:

if spack.version.Version(spack.spack_version) >= spack.version.Version("0.17"):

Note that the spack module is not imported in the script. This PR fixes this by changing this line to:

if Version(spack_version) >= Version("0.17"):

and adding the appropriate imports:

from spack import spack_version
from spack.error import SpackError
from spack.package import *
from spack.directives import directive
from spack.version import Version

PR Checklist

I tried figuring out how to check if the code is properly formatted, but failed. I'd be happy to do it if you can provide me with instructions.

• Adds a test for any bugs fixed. Adds tests for new features.
• Format your changes by using the make format command after configuring with cmake.
• Document any new features, update documentation for changes made.
• Make sure the copyright notice on any files you modified is up to date.
• After creating a pull request, note it in the CHANGELOG.md file.
• LANL employees: make sure tests pass both on the github CI and on the Darwin CI

If preparing for a new release, in addition please check the following:

• Update the version in cmake.
• Move the changes in the CHANGELOG.md file under a new header for the new release, and reset the categories.
• Ensure that any when='@main' dependencies are updated to the release version in the package.py

[Yurlungur]

Thanks for the fix!