File file = new File(rootDir, "file-that-doesnt-exist");

    assertThat(Files.fileTraverser().breadthFirst(file)).containsExactly(file);
  }

  public void testFileTraverser_file() throws Exception {
    File file = newFile("some-file");

    assertThat(Files.fileTraverser().breadthFirst(file)).containsExactly(file);
  }

  public void testFileTraverser_singleFile() throws Exception {

    Path file = rootDir.resolve("file-that-doesnt-exist");

    assertThat(MoreFiles.fileTraverser().breadthFirst(file)).containsExactly(file);
  }

  public void testFileTraverser_file() throws Exception {
    Path file = newFile("some-file");

    assertThat(MoreFiles.fileTraverser().breadthFirst(file)).containsExactly(file);
  }

  public void testFileTraverser_singleFile() throws Exception {