[JENKINS-41321] Add option for different refspec for polling and clone during build

To speed up the build I want to use a refspec to only clone the needed branch like this:

refs/heads/$GIT_LOCAL_BRANCH:refs/remotes/$GIT_BRANCH

This seemed to work great at first, but then I found out this refspec is also used during polling.

This means that not all branches are being built anymore, even though our branch specifier is '**', because they are simply not fetched anymore.

This is why I would like to have an option to specify a different refspec for the build than for the polling. So I can have these refspecs:

polling: refs/heads/*:refs/remotes/*

building: refs/heads/$GIT_LOCAL_BRANCH:refs/remotes/$GIT_BRANCH

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Originally reported by jeltef, imported from: Add option for different refspec for polling and clone during build

• status: Open
  
• priority: Minor
  
• component(s): git-plugin, github-plugin
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 1
  
• imported: 2025-12-02
  

To speed up the build I want to use a refspec to only clone the needed branch like this:

refs/heads/$GIT_LOCAL_BRANCH:refs/remotes/$GIT_BRANCH


This seemed to work great at first, but then I found out this refspec is also used during polling.

This means that not all branches are being built anymore, even though our branch specifier is '**', because they are simply not fetched anymore.


This is why I would like to have an option to specify a different refspec for the build than for the polling. So I can have these refspecs:

polling: refs/heads/*:refs/remotes/*

building: refs/heads/$GIT_LOCAL_BRANCH:refs/remotes/$GIT_BRANCH