CollectorTester.of(
            ImmutableRangeMap.<Range<Integer>, Integer, Integer>toImmutableRangeMap(
                k -> k, k -> k.lowerEndpoint()))
        .expectCollects(rangeMap, rangeOne, rangeTwo);
  }

            .and(Equivalence.equals().onResultOf(ImmutableSortedSet::asList))
            .and(Equivalence.equals());
    CollectorTester.of(collector, equivalence)
        .expectCollects(
            ImmutableSortedSet.of("a", "b", "c", "d"), "a", "b", "a", "c", "b", "b", "d");
  }

  public void testToImmutableSortedSet_customComparator() {

        () -> ImmutableList.sortedCopyOf(String.CASE_INSENSITIVE_ORDER, (Collection<String>) c));
  }

  public void testToImmutableList() {
    CollectorTester.of(ImmutableList.<String>toImmutableList())
        .expectCollects(ImmutableList.of("a", "b", "c", "d"), "a", "b", "c", "d");
  }

  // Basic tests

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointers() {