raise util.Abort again if specified revision is not an integer. This was changed to NoRepo in 462cc56d898f, because specifying non-integer revisions for e.g. the Mercurial backend caused Abort to be raised in the subversion importer. Now util.Abort is raised again, but the check is done after verifying if it really is a subversion repository.

abort: repository a not found!
255
abort: error: Connection refused
255
abort: repository a not found!
255
abort: destination '../a' already exists
255
abort: repository a not found!
255
destination directory: q
abort: destination 'q' already exists