[JENKINS-31925] GitSCM default values not properly defined

For use with Workflow's Snippet Generator, GitSCM needs to use @​DataBoundSetter on optional fields and ensure that the default value is equal to what an unconfigured config.jelly would set. Otherwise the user is offered unnecessary overrides such as extensions: [].

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Originally reported by jglick, imported from: GitSCM default values not properly defined

• status: Open
  
• priority: Minor
  
• component(s): git-plugin
  
• label(s): pipeline
  
• resolution: Unresolved
  
• votes: 0
  
• watchers: 3
  
• imported: 2025-12-02
  

For use with Workflow's Snippet Generator, GitSCM needs to use @DataBoundSetter on optional fields and ensure that the default value is equal to what an unconfigured config.jelly would set. Otherwise the user is offered unnecessary overrides such as extensions: [].