Steps to reproduce

When there is a newer version of an R-package published on cran, fetching the older versions does not work in spack anymore.
e.g. r-ellipsis

• newest version in spack is 0.3.1 (before r-ellipsis: add 0.3.2 #26965 is merged)
• newest version on cran 0.3.2
• running spack checksum r-ellipsis@0.3.1 fails with the error message

» spack checksum r-ellipsis@0.3.1 
==> Found 1 version of r-ellipsis:
  
  0.3.1  https://cloud.r-project.org/src/contrib/ellipsis_0.3.1.tar.gz

==> Something failed on https://cloud.r-project.org/src/contrib/ellipsis_0.3.1.tar.gz, skipping.  (All fetchers failed for spack-stage-z032nuxl)
==> Error: Could not fetch any versions for r-ellipsis

but spack checksum r-ellipsis@0.3.2 works.

Also spack install r-ellipsis0.3.1 works, because it fetches the sources from the spack mirror and not from cran.

Reason:
spack tries to get the sources from https://cloud.r-project.org/src/contrib/ellipsis_0.3.1.tar.gz but https://cloud.r-project.org/src/contrib only provides the newest version (here 0.3.2), older versions are migrated to https://cloud.r-project.org/src/contrib/Archive/ellipsis. Thus spack checksum fails for old versions of the package (I checked all old versions in spack: 0.3.1, 0.3.0, 0.2.0.1).

I tried to migrate to using the cran attribute instead of explicit url and list_url but that does not change anything.

All R-packages I tested had this problem regarding older versions, e.g.

• r-rcpp@1.0.6,
• r-broom@0.3.1
• r-lifecycle@0.2.0
• r-lme4@1.1-27

ping @glennpj as R maintainer

Error message

No response

Information on your system

• Spack: 0.16.3-5036-7884fc8973
• Python: 3.8.10
• Platform: linux-fedora32-haswell
• Concretizer: clingo

General information

• I have run spack debug report and reported the version of Spack/Python/Platform
• I have searched the issues of this repo and believe this is not a duplicate
• I have run the failing commands in debug mode and reported the output