assertThat(immutableValueGraph.asGraph()).isInstanceOf(ImmutableGraph.class);
    assertThat(immutableValueGraph).isNotInstanceOf(MutableValueGraph.class);
    assertThat(immutableValueGraph).isEqualTo(mutableValueGraph);

    mutableValueGraph.addNode("B");
    assertThat(immutableValueGraph).isNotEqualTo(mutableValueGraph);
  }

  @Test
  public void copyOfImmutableValueGraph_optimized() {

    ListenableFuture<String> f =
        new SimpleForwardingListenableFuture<String>(immediateFuture("a")) {};
    verify(!(f instanceof FluentFuture));
    assertThat(FluentFuture.from(f).get()).isEqualTo("a");
    // TODO(cpovirk): Test forwarding more extensively.
  }

  public void testAddCallback() {
    FluentFuture<String> f = FluentFuture.from(immediateFuture("a"));
    final boolean[] called = new boolean[1];

    assertThat(immutableNetwork.asGraph()).isInstanceOf(ImmutableGraph.class);
    assertThat(immutableNetwork).isNotInstanceOf(MutableNetwork.class);
    assertThat(immutableNetwork).isEqualTo(mutableNetwork);

    mutableNetwork.addNode("B");
    assertThat(immutableNetwork).isNotEqualTo(mutableNetwork);
  }

  @Test
  public void copyOfImmutableNetwork_optimized() {

  public void testPreOrder() {
    assertThat(iterationOrder(ADAPTER.preOrderTraversal(h))).isEqualTo("hdabcegf");
  }

  public void testPostOrder() {
    assertThat(iterationOrder(ADAPTER.postOrderTraversal(h))).isEqualTo("abcdefgh");
  }

  public void testBreadthOrder() {
    assertThat(iterationOrder(ADAPTER.breadthFirstTraversal(h))).isEqualTo("hdegabcf");
  }

  public void testUsing() {

public class FuturesGetDoneTest extends TestCase {
  public void testSuccessful() throws ExecutionException {
    assertThat(getDone(immediateFuture("a"))).isEqualTo("a");
  }

  public void testSuccessfulNull() throws ExecutionException {
    assertThat(getDone(Futures.<@Nullable String>immediateFuture(null))).isEqualTo(null);
  }

  public void testFailed() {
    Exception failureCause = new Exception();
    try {

          }
        };
    addCallback(future, callback, directExecutor());
    future.set(result);
    assertEquals(result, future.get());
    assertThat(successCalls[0]).isEqualTo(1);
    assertThat(failureCalls[0]).isEqualTo(0);
  }

  public void testOnSuccessThrowsError() throws Exception {
    class TestError extends Error {}
    TestError error = new TestError();
    String result = "result";

    g2.addEdge(N1, N2, E12);

    assertThat(g1).isEqualTo(g2);
  }

  @Test
  public void equivalent_edgeDirectionsDiffer() {
    network.addEdge(N1, N2, E12);

    MutableNetwork<Integer, String> g2 = createNetwork(edgeType);
    g2.addEdge(N2, N1, E12);

    switch (edgeType) {
      case UNDIRECTED:
        assertThat(network).isEqualTo(g2);
        break;
      case DIRECTED:

    assertThat(SignedBytes.saturatedCast(LEAST - 1L)).isEqualTo(LEAST);
    assertThat(SignedBytes.saturatedCast(Long.MAX_VALUE)).isEqualTo(GREATEST);
    assertThat(SignedBytes.saturatedCast(Long.MIN_VALUE)).isEqualTo(LEAST);
  }

  private static void assertCastFails(long value) {
    try {
      SignedBytes.checkedCast(value);
      fail("Cast to byte should have failed: " + value);
    } catch (IllegalArgumentException ex) {

    assertThat(network.edgeOrder()).isEqualTo(unordered());
    assertThat(network.nodeOrder()).isEqualTo(insertion()); // default
  }

  @Test
  public void edgeOrder_insertion() {
    MutableNetwork<Integer, String> network =
        NetworkBuilder.directed().edgeOrder(insertion()).build();

    addEdges(network);

    assertThat(network.edgeOrder()).isEqualTo(ElementOrder.insertion());

  }

  public void testVerify_simpleMessage_failure() {
    try {
      verify(false, "message");
      fail();
    } catch (VerifyException expected) {
      assertThat(expected).hasMessageThat().isEqualTo("message");
    }
  }

  public void testVerify_complexMessage_success() {
    verify(true, "%s", IGNORE_ME);
  }

  public void testVerify_complexMessage_failure() {
    try {