assertThrows(NullPointerException.class, () -> result.next());
    // There is no way to get "through" to the 3.  Buh-bye
  }

  public void testConcatVarArgsContainingNull() {
    assertThrows(
        NullPointerException.class,
        () ->
            Iterators.concat(
                iterateOver(1, 2), null, iterateOver(3), iterateOver(4), iterateOver(5)));
  }