@Test
public void testSingletonMap() {
Long2DoubleSortedMap map = new Long2DoubleSortedArrayMap(SortedKeyIndex.create(42),
new double[]{3.5});
assertThat(map.get(42L), equalTo(3.5));
assertThat(map.size(), equalTo(1));
assertThat(map.isEmpty(), equalTo(false));
assertThat(map.keySet(), contains(42L));
assertThat(map.values(), contains(3.5));
assertThat(map.entrySet(), hasSize(1));
assertThat(map.firstLongKey(), equalTo(42L));
assertThat(map.lastLongKey(), equalTo(42L));
Map.Entry<Long, Double> ent = map.entrySet().first();
assertThat(ent, notNullValue());
assertThat(ent.getKey(), equalTo(42L));
assertThat(ent.getValue(), equalTo(3.5));
assertThat(map.entrySet().contains(Pair.of(42L, 3.5)),
equalTo(true));
assertThat(map.entrySet().contains(Pair.of(42L, 3.7)),
equalTo(false));
assertThat(map.entrySet().contains(Pair.of(41L, 3.5)),
equalTo(false));
assertThat(map.entrySet().first(), equalTo((Object) Pair.of(42L, 3.5)));
assertThat(map.entrySet().last(), equalTo((Object) Pair.of(42L, 3.5)));
}