MRPipeline.plan() does not clear up the temporary hadoop-<username> folder it creates

As a user i just want to run MRPipeline.plan() to retrieve the PlanningParameters.PIPELINE_PLAN_DOTFILE for the current pipeline configuration. However it appears that since we don't actually call run(), the Map that is created to hold outputTargets still has items in it, and the cleanup() method will not execute under the condition of having elements in it, to delete the tmp directory that gets created when creating a new MRPipeline object. Since we don't really want to execute the code if we just want to create a plan then I don't know how we can cleanup this Map. Basically the temporary hadoop folders left behind is our problem.