private FileVisitDetails expectSpecAndDirVisited() {
    final Collector<FileVisitDetails> collector = collector();

    context.checking(
        new Expectations() {
          {
            one(delegate).visitSpec(spec);
            one(delegate).visitDir(with(not(sameInstance(details))));

            will(collectTo(collector));
          }
        });

    visitor.visitSpec(spec);
    visitor.visitDir(details);

    return collector.get();
  }