private void assertParentAndSelf(Directory dir, File parent, File self) {
    assertThat(dir).isEqualTo(self);
    assertThat(dir.parent()).isEqualTo(parent);

    assertThat(dir.get(PARENT)).isEqualTo(entry((Directory) self, "..", parent));
    assertThat(dir.get(SELF)).isEqualTo(entry((Directory) self, ".", self));
  }
Tests for {@link Directory}.

@author Colin Decker
jimfs/src/test/java/com/google/common/jimfs/DirectoryTest.java