}

  public void testToString() {
    Set<String> set = of("a", "b", "c", "d", "e", "f", "g");
    assertThat(set.toString()).isEqualTo("[a, b, c, d, e, f, g]");
  }

  @GwtIncompatible // slow (~40s)
  public void testIterator_oneElement() {
    new IteratorTester<String>(
        5, UNMODIFIABLE, singleton("a"), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override

    }.test();
  }

  @GwtIncompatible // fairly slow (~40s)
  public void testConcatSingletonAndSingletonYieldsDoubleton() {
    new DoubletonIteratorTester() {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.concat(iterateOver(1), iterateOver(2));
      }
    }.test();
  }

  @GwtIncompatible // fairly slow (~40s)

    }.test();
  }

  @GwtIncompatible // fairly slow (~40s)
  public void testConcatSingletonAndSingletonYieldsDoubleton() {
    new DoubletonIteratorTester() {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.concat(iterateOver(1), iterateOver(2));
      }
    }.test();
  }

  @GwtIncompatible // fairly slow (~40s)