ImmutableGraph<String> immutableGraph = ImmutableGraph.copyOf(mutableGraph);

    assertThat(immutableGraph).isNotInstanceOf(MutableValueGraph.class);
    assertThat(immutableGraph).isEqualTo(mutableGraph);

    mutableGraph.addNode("B");
    assertThat(immutableGraph).isNotEqualTo(mutableGraph);
  }

  @Test
  public void copyOfImmutableGraph_optimized() {

 * graph.putEdge("bread", "bread");
 * graph.putEdge("chocolate", "peanut butter");
 * graph.putEdge("peanut butter", "jelly");
 *
 * // Building an immutable graph
 * ImmutableGraph<String> immutableGraph =
 *     GraphBuilder.undirected()
 *         .allowsSelfLoops(true)
 *         .<String>immutable()
 *         .putEdge("bread", "bread")
 *         .putEdge("chocolate", "peanut butter")

      ValueGraphBuilder.directed().allowsSelfLoops(true).expectedNodeCount(16);

  private static final ImmutableGraph<String> IMMUTABLE_GRAPH_A =
      GraphBuilder.directed().<String>immutable().addNode("A").build();
  private static final ImmutableGraph<String> IMMUTABLE_GRAPH_B =
      GraphBuilder.directed().<String>immutable().addNode("B").build();

 * you should use the non-mutating {@link Graph} interface, or an {@link ImmutableGraph}.
 *
 * <p>You can create an immutable copy of an existing {@code Graph} using {@link
 * ImmutableGraph#copyOf(Graph)}:
 *
 * {@snippet :
 * ImmutableGraph<Integer> immutableGraph = ImmutableGraph.copyOf(graph);
 * }
 *
 * <p>Instances of {@link ImmutableGraph} do not implement {@link MutableGraph} (obviously!) and are

    return checkNotNull(graph);
  }

  @Override
  public ElementOrder<N> incidentEdgeOrder() {
    return ElementOrder.stable();
  }

  @Override
  public ImmutableGraph<N> asGraph() {
    return new ImmutableGraph<>(this); // safe because the view is effectively immutable
  }

  private static <N, V> ImmutableMap<N, GraphConnections<N, V>> getNodeConnections(
      ValueGraph<N, V> graph) {

   *
   * @since NEXT
   */
  // TODO(b/31438252): Consider optimizing for undirected graphs.
  public static <N> ImmutableGraph<N> transitiveClosure(
      Graph<N> graph, TransitiveClosureSelfLoopStrategy strategy) {
    ImmutableGraph.Builder<N> transitiveClosure =
        GraphBuilder.from(graph).allowsSelfLoops(true).<N>immutable();

    for (N node : graph.nodes()) {

 * ImmutableNetwork}.
 *
 * <p>You can create an immutable copy of an existing {@code Network} using {@link
 * ImmutableNetwork#copyOf(Network)}:
 *
 * {@snippet :
 * ImmutableNetwork<Integer, MyEdge> immutableGraph = ImmutableNetwork.copyOf(network);
 * }
 *
 * <p>Instances of {@link ImmutableNetwork} do not implement {@link MutableNetwork} (obviously!) and
 * are contractually guaranteed to be unmodifiable and thread-safe.
 *

        return Ordering.natural().immutableSortedCopy(graphMap.get(node));
      }
    };
  }

  private static ImmutableGraph<Character> createSingleRootGraph() {
    MutableGraph<Character> graph = GraphBuilder.directed().build();
    graph.addNode('a');
    return ImmutableGraph.copyOf(graph);
  }

  private static void assertEqualCharNodes(Iterable<Character> result, String expectedCharacters) {

  @Parameters(name = "allowsSelfLoops={0}")
  public static Collection<Object[]> parameters() {
    return Arrays.asList(new Object[][] {{false}, {true}});
  }

  private final boolean allowsSelfLoops;
  private ImmutableGraph.Builder<Integer> graphBuilder;

  public StandardImmutableDirectedGraphTest(boolean allowsSelfLoops) {
    this.allowsSelfLoops = allowsSelfLoops;
  }

  @Override
  public Graph<Integer> createGraph() {

  @Parameters(name = "allowsSelfLoops={0}")
  public static Collection<Object[]> parameters() {
    return Arrays.asList(new Object[][] {{false}, {true}});
  }

  private final boolean allowsSelfLoops;
  private ImmutableGraph.Builder<Integer> graphBuilder;

  public StandardImmutableUndirectedGraphTest(boolean allowsSelfLoops) {
    this.allowsSelfLoops = allowsSelfLoops;
  }

  @Override
  public Graph<Integer> createGraph() {