Spack V1 Migration Feature: Reserved Spack Definitions

[CodeGat]

Closes #330
Will be merged into #326

Background

Root specs are very meaningful in our infrastructure. This comes with a few downsides, mostly in the cases where we have multiple specs in the speclist, or regular users want to use prerelease manifests in their own instances but can't due to prerelease-specific modifications of the root spec.

In this PR, we move away from important information being in the .spack.specs[0] field, and instead use reserved, dummy definitions at the top of the file:

spack:
  definitions:
  - _name: [access-om2]
  - _version: [2025.11.000]
  specs:
  - access-om2
  # ...

This means that speclists can be free from infra-specific information, and they are open to future modification.

The PR

• Rename the get-spack-root-spec action to the more apt get-spack-manifest
  • Also update the outputs - simplified to deployment-{name|version} outputs, equivalent to .spack.definitions[]._{name|version}[0] fields.
• Update all usages of the get-spack-root-spec action to get-spack-manifest
• Update the internals of injection to allow multiple of the same spec, using this rule:
  • If there are no projections defined, make them of the form {name}/prX-Y/{hash:7}
  • If there are projections defined, infix the deployment number. This is of the form: {name}/prX-Y/DEMARCATOR, where the DEMARCATOR is the defined projection. For example, {name}/prX-Y/{variants.x}x{variants.y}
  • This is the same for Releases, except using the _version. It is not yet allowed in Releases.

Testing

Testing Details in this collapsed section

Unit Tests

Done via pytest, all pass.

MDR Testing

Done for regular MDRs in ACCESS-NRI/ACCESS-TEST#60

Prerelease (Draft)

Success, see https://github.com/ACCESS-NRI/ACCESS-TEST/actions/runs/19916256065

Prerelease (Ready For Review)

Success, see https://github.com/ACCESS-NRI/ACCESS-TEST/actions/runs/20013811438

Prerelease (!redeploy)

Expected failure, since the schema version updates are not yet on the main branch (since comment triggers are technically in the context of the main branch). But, the only points of difference (The status setting in https://github.com/ACCESS-NRI/ACCESS-TEST/actions/runs/20014778511/job/57390074093 and https://github.com/ACCESS-NRI/ACCESS-TEST/actions/runs/20014778511/job/57390091047) succeeded as expected.

Software Deployment Repository Testing

Done for Software Deployment Repostiories in ACCESS-NRI/system-tools#19

Prerelease (Draft)

Succeeded, see https://github.com/ACCESS-NRI/system-tools/actions/runs/20151461268?pr=19

Prerelease (Ready For Review)

Succeeded. see https://github.com/ACCESS-NRI/system-tools/actions/runs/20217336546?pr=19

Prerelease (!redeploy)

Expected failure, since the schema version updates are not yet on the main branch (since comment triggers are technically in the context of the main branch). But, the only points of difference (The status setting in https://github.com/ACCESS-NRI/system-tools/actions/runs/20217823516/job/58033899157 and https://github.com/ACCESS-NRI/system-tools/actions/runs/20217823516/job/58033912451) succeeded as expected.

[CodeGat]

This looks about ready to go!

[aidanheerdegen]

An initial pass, but might need a peer-review to ask some more questions.

[CodeGat]

After the rebase onto v7, I note that it still works fine 👍 See ACCESS-NRI/ACCESS-TEST#60 (comment)

[CodeGat]

After the rebase, I note it has passed testing: ACCESS-NRI/ACCESS-TEST#60 (comment)

[aidanheerdegen]

LGTM, thanks! Nice work.