def resolve_revision
      revision = @repository.tag.to_s.strip
      if revision.empty?
        revision = nil
      elsif (revision =~ SVN_REVISION_REGEX).nil?
        raise RetrieverError, "Revision reference contained illegal characters: #{revision.inspect}"
      end
      # timestamps can contain spaces; surround them with double quotes.
      revision = revision.inspect if revision.index(' ')
      revision
    end
def resolve_revision
      revision = @repository.tag.to_s.strip
      if revision.empty?
        revision = nil
      elsif (revision =~ SVN_REVISION_REGEX).nil?
        raise RetrieverError, "Revision reference contained illegal characters: #{revision.inspect}"
      end
      # timestamps can contain spaces; surround them with double quotes.
      revision = revision.inspect if revision.index(' ')
      revision
    end
ignoring additional info after revision