We may just want to get the latest Subversion repository itself rather than for a workspace for a dynamic Jenkins job parameter. Using svnkit is difficult in this case as explained in Get Subversion Revision For Workspace in Jenkins. The following can get used in a Scriptler script for a dynamic parameter to get the latest or HEAD revision:
def pSvn = ("svn info -r HEAD $SvnUrl").execute() def sout = new StringBuffer() pSvn.consumeProcessOutput(sout, null) pSvn.waitFor() def currentTags = sout.toString().trim() def mt = currentTags =~ /Revision\:\s+(\d+)/ return mt
SvnUrl as the only parameter and set its value to the proper repository URL when defining the dynamic parameter.