[JENKINS-38675] gerrit trigger git summary show refspec instead of branch

When you have multiple git projects in a pipeline build, multiple git summary bits appear in the build information when you highlight the build. These currently show something like

Revision:

• a built branch


• another built branch

When using the gerrit trigger plugin, the "built branches" only show the name of the branch from $GERRIT_BRANCH, instead of showing a refspec. Ideally when using these together, we should see the refspec instead of the branch because this is really what was built by the job.

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Originally reported by jekeller, imported from: gerrit trigger git summary show refspec instead of branch

• assignee: rsandell
  
• status: In Progress
  
• priority: Minor
  
• component(s): gerrit-trigger-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 3
  
• imported: 2025-12-06
  

When you have multiple git projects in a pipeline build, multiple git summary bits appear in the build information when you highlight the build. These currently show something like


<git image> Revision: <sha1id of checked out source>



	
a built branch

	
another built branch



When using the gerrit trigger plugin, the "built branches" only show the name of the branch from $GERRIT_BRANCH, instead of showing a refspec. Ideally when using these together, we should see the refspec instead of the branch because this is really what was built by the job.

Start by tracing how the gerrit-trigger-plugin handles GERRIT_BRANCH and how the Git summary is produced for pipeline builds; the payload names no files or tests. Confirm the current display with multiple Git projects, then make the built-branch summary show the refspec used by the job and verify the result with the repository's existing tests.

Written by the indexing model from the issue text.