Jenkins Force Multibranch Pipeline to Honor Jenkinsfile

Question

I have a multibranch pipeline which monitors a repository of hundreds to thousands of branches.

Each job under this multibranch pipeline does NOT require a full checkout, and a single branch checkout is preferred (a full checkout slows down the job by quite a bit).

The Jenkinsfile for this job is stored in Jenkins "Managed Files" section. I have modified this Jenkinsfile such that only a subset of branches should be checked out on job run:

    ...
    checkout([
         $class: 'GitSCM',
         branches: [[name: JOB_NAME.minus('foo/')],
         doGenerateSubmoduleConfigurations: scm.doGenerateSubmoduleConfigurations,
         extensions: scm.extensions,
         userRemoteConfigs: scm.userRemoteConfigs
    ])
    ...

However this setting is not honored. When a new build is triggered for one of the branches a full discover/checkout is performed in the job. This happens with "Build Now" and "Rebuild".

If I make use of a the "Replay" functionality on a given job however I am first presented with the correctly updated Jenkinsfile and running that replay performs the above checkout correctly (i.e. one branch).

How do I get this (a single branch checkout as specified in the Jenkinsfile) to always happen?

I have tried:

• Deleting and recreating the job (as stored as DSL)
• Manually updating the multibranch pipeline configuration
• Deleting all FS XML as it related to previous "Managed Files" version on the Jenkins master
• Jenkins restarts

I would expect that the Jenkinfile setting would be honored, however a full checkout is always performed.