checkout([$class: 'GitSCM', 
      branches: [[name: "origin/test"], [name: "origin/master"]], 
      doGenerateSubmoduleConfigurations: false, 
      submoduleCfg: [], 
      userRemoteConfigs: [[url: 'some url',
                           credentialsId: 'some creds']],
      extensions: [
          [$class: 'PruneStaleBranch'],
          [$class: 'CleanBeforeCheckout'],
          [$class: 'BuildChooserSetting', buildChooser: [$class: 'AlternativeBuildChooser']]
      ]
    ])

java.lang.ClassCastException: org.jenkinsci.plugins.workflow.job.WorkflowRun cannot be cast to hudson.model.AbstractBuild
	at org.jenkinsci.plugins.git.chooser.alternative.AlternativeBuildChooser$1.invoke(AlternativeBuildChooser.java:44)
	at hudson.plugins.git.GitSCM$BuildChooserContextImpl.actOnBuild(GitSCM.java:907)
	at org.jenkinsci.plugins.git.chooser.alternative.AlternativeBuildChooser.getCandidateRevisions(AlternativeBuildChooser.java:44)
	at hudson.plugins.git.GitSCM.determineRevisionToBuild(GitSCM.java:995)
	at hudson.plugins.git.GitSCM.checkout(GitSCM.java:1098)
	at org.jenkinsci.plugins.workflow.steps.scm.SCMStep.checkout(SCMStep.java:109)
	at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:83)
	at org.jenkinsci.plugins.workflow.steps.scm.SCMStep$StepExecutionImpl.run(SCMStep.java:73)
	at org.jenkinsci.plugins.workflow.steps.AbstractSynchronousNonBlockingStepExecution$1$1.call(AbstractSynchronousNonBlockingStepExecution.java:49)
	at hudson.security.ACL.impersonate(ACL.java:213)
	at org.jenkinsci.plugins.workflow.steps.AbstractSynchronousNonBlockingStepExecution$1.run(AbstractSynchronousNonBlockingStepExecution.java:47)
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
	at java.util.concurrent.FutureTask.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)