* directory.
   */
  protected final File getTempDir() throws IOException {
    if (tempDir == null) {
      tempDir = createTempDir();
    }

    return tempDir;
  }

  /**
   * Creates a new temp file in the temp directory returned by {@link #getTempDir()}. The file will
   * be deleted in the tear-down for this test.
   */

  }

  public void testCreateParentDirs_noParentsNeeded() throws IOException {
    File file = file(getTempDir(), "nonexistent.file");
    assertTrue(file.getParentFile().exists());
    Files.createParentDirs(file);
  }

  public void testCreateParentDirs_oneParentNeeded() throws IOException {
    File file = file(getTempDir(), "parent", "nonexistent.file");
    File parent = file.getParentFile();
    assertFalse(parent.exists());

  }

  public void testCreateParentDirs_noParentsNeeded() throws IOException {
    File file = file(getTempDir(), "nonexistent.file");
    assertTrue(file.getParentFile().exists());
    Files.createParentDirs(file);
  }

  public void testCreateParentDirs_oneParentNeeded() throws IOException {
    File file = file(getTempDir(), "parent", "nonexistent.file");
    File parent = file.getParentFile();
    assertFalse(parent.exists());