@Test
public void testAsMap() {

    Fact<Integer> fact1 = new Fact<>("foo", 1);
    Fact<Integer> fact2 = new Fact<>("bar", 2);
    facts.add(fact1);
    facts.add(fact2);
    Map<String, Object> map = facts.asMap();
    assertThat(map).containsKeys("foo", "bar");
    assertThat(map).containsValues(1, 2);
}