public void testUseAsDefaultsForComposition() {
    assertEquals(EMPTY.user("c"), test("a", "b", "c"));
    assertEquals(EMPTY.user("c"), test("a", null, "c"));
    assertEquals(EMPTY.user("c"), test(null, "b", "c"));

    assertEquals(EMPTY.user("b"), test("a", "b", null));
    assertEquals(EMPTY.user("a"), test("a", null, null));
    assertEquals(EMPTY.user("b"), test(null, "b", null));
  }
 public FileAttributes test(String defaultDefaultUser, String defaultUser, String user) {
   return EMPTY
       .user(defaultDefaultUser)
       .useAsDefaultsFor(EMPTY.user(defaultUser))
       .useAsDefaultsFor(EMPTY.user(user));
 }
  public void testEquals() {
    assertEquals(EMPTY, EMPTY);

    assertFalse(EMPTY.user("trygve").equals(EMPTY));
  }