@Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.cycle(asList(1, 2));
      }
    }.test();
  }

  @GwtIncompatible // slow (~5s)
  public void testConcatNoIteratorsYieldsEmpty() {
    new EmptyIteratorTester() {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.concat();
      }
    }.test();
  }

      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.cycle(asList(1, 2));
      }
    }.test();
  }

  @GwtIncompatible // slow (~5s)
  public void testConcatNoIteratorsYieldsEmpty() {
    new EmptyIteratorTester() {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.concat();
      }
    }.test();
  }