assertThrows(
        NullPointerException.class,
        () -> Stream.of(immutableCell("one", "uno", 1)).collect(collector));
  }

  // https://youtrack.jetbrains.com/issue/KT-58242/. Crash when columnFunction result (null) is
  // unboxed
  @J2ktIncompatible
  public void testToImmutableTableNullColumnKey() {
    Collector<Cell<String, String, Integer>, ?, ImmutableTable<String, String, Integer>> collector =