public void unlink(Name name) {
    DirectoryEntry entry = remove(checkNotReserved(name, "unlink"));
    entry.file().unlinked();
  }
@Test
  public void testUnlink() {
    assertThat(root.get(Name.simple("foo"))).isNotNull();

    root.unlink(Name.simple("foo"));

    assertThat(root.get(Name.simple("foo"))).isNull();
  }