code: @VisibleForTesting
    protected StreamSet createStreamSet(final Terminal terminal) {
      InputStream in = new FilterInputStream(terminal.input())
      {
        @Override
        public void close() throws IOException {
          // ignore
        }
      };
      PrintStream out = new PrintStream(terminal.output(), true)
      {
        @Override
        public void close() {
          // ignore
        }
      };
      return new StreamSet(in, out);
    }
docs: Create the {@link StreamSet} used to register.