Validation for Task Result expressions in Pipeline Result

[vsinghai]

Changes

Prior to this commit, the validation for static strings for Task Result expressions in Pipeline Results was not extensive.

This commit adds the case where a pipeline would be invalid if there is no expression following the valid form
$(tasks.<task-name>.results.<result-name>).

Please reference this doc for more information.

Fixes bug #4922

/kind bug
/cc @jerop

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• Docs included if any changes are user facing
• Tests included if any functionality added or changed
• Follows the commit message standard
• Meets the Tekton contributor standards (including
  functionality, content, code)
• Release notes block below has been filled in
  (if there are no user facing changes, use release note "NONE")

Release Notes

Fixed a bug where static strings where not invalidated in `Pipeline Results`.

[tekton-robot]

Hi @vsinghai. Thanks for your PR.

I'm waiting for a tektoncd member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[jerop]

welcome @vsinghai 🎉
/meow

/ok-to-test

[tekton-robot]

@jerop:

In response to this:

welcome @vsinghai 🎉
/meow

/ok-to-test

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[jerop]

@vsinghai please do the following:

• update the PR title
• reference the issue in the commit and/or PR body - Validation for Task Result expression in Pipeline Results not working #4922
• squash the commits - https://github.com/tektoncd/community/blob/main/standards.md#commits
• add release notes (none)
• check of the submitter checklist

[jerop]

@vsinghai this solution fixes part of bug #4922 - addresses initialized-2 but not initialized-3 - just wanted to confirm that it'd addressed separately (prefer the smaller PR anyway)

  results:
    - name: initialized-1 
      value: $(tasks.check-git-commit.results.init)
    - name: initialized-2 
      value: this is static 
    - name: initialized-3
      value: $(foo.bar)

/approve

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jerop

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• pkg/apis/OWNERS [jerop]

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[dibyom]

one tiny nit, otherwise looks good!

[dibyom]

/lgtm

[pritidesai]

@vsinghai thank you for this 👍 Welcome to the community 🎉

Please update the release notes since this is fixing a bug and will be very beneficial to the users consuming these changes 🙏

[jerop]

/test pull-tekton-pipeline-alpha-integration-tests