@Test
  public void testInitialAttributes() {
    // no initial attributes
    assertThat(ImmutableList.copyOf(file.getAttributeKeys())).isEmpty();
    assertThat(provider.attributes(file)).isEmpty();
  }
Tests for {@link UserDefinedAttributeProvider}.

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