AbstractGraphTest.validateGraph(asGraph);
    assertThat(graph.nodes()).isEqualTo(asGraph.nodes());
    assertThat(graph.edges()).isEqualTo(asGraph.edges());
    assertThat(graph.nodeOrder()).isEqualTo(asGraph.nodeOrder());
    assertThat(graph.incidentEdgeOrder()).isEqualTo(asGraph.incidentEdgeOrder());
    assertThat(graph.isDirected()).isEqualTo(asGraph.isDirected());
    assertThat(graph.allowsSelfLoops()).isEqualTo(asGraph.allowsSelfLoops());

    assertThat(network.nodes()).containsExactly(N1, N5, N4, N2, N3);
    assertThat(network.edges()).containsExactly(E15, E41, E23);
    assertThat(network.edgesConnecting(N1, N5)).containsExactly(E15);
    assertThat(network.edgesConnecting(N4, N1)).containsExactly(E41);
    assertThat(network.edgesConnecting(N2, N3)).containsExactly(E23);
    assertThat(network.edgesConnecting(N3, N2)).containsExactly(E23);

    assertTrue(networkAsMutableNetwork.addEdge(N2, N3, E23));
    assertThat(network.nodes()).containsExactly(N1, N5, N4, N2, N3);
    assertThat(network.edges()).containsExactly(E15, E41, E23);
    assertThat(network.edgesConnecting(N1, N5)).containsExactly(E15);
    assertThat(network.edgesConnecting(N4, N1)).containsExactly(E41);
    assertThat(network.edgesConnecting(N2, N3)).containsExactly(E23);

    putEdge(N1, N2);
    putEdge(N4, N1);
    assertThat(graphAsMutableGraph.removeNode(N1)).isTrue();
    assertThat(graphAsMutableGraph.removeNode(N1)).isFalse();
    assertThat(graph.nodes()).containsExactly(N2, N4);

    assertThat(graph.adjacentNodes(N2)).isEmpty();
    assertThat(graph.predecessors(N2)).isEmpty();
    assertThat(graph.successors(N2)).isEmpty();
    assertThat(graph.incidentEdges(N2)).isEmpty();

  public void testConcat() {
    assertThat(Ints.concat()).isEqualTo(EMPTY);
    assertThat(Ints.concat(EMPTY)).isEqualTo(EMPTY);
    assertThat(Ints.concat(EMPTY, EMPTY, EMPTY)).isEqualTo(EMPTY);
    assertThat(Ints.concat(ARRAY1)).isEqualTo(ARRAY1);
    assertThat(Ints.concat(ARRAY1)).isNotSameInstanceAs(ARRAY1);
    assertThat(Ints.concat(EMPTY, ARRAY1, EMPTY)).isEqualTo(ARRAY1);
    assertThat(Ints.concat(ARRAY1, ARRAY1, ARRAY1))

    }
  }

  public void testContains() {
    assertThat(Floats.contains(EMPTY, (float) 1)).isFalse();
    assertThat(Floats.contains(ARRAY1, (float) 2)).isFalse();
    assertThat(Floats.contains(ARRAY234, (float) 1)).isFalse();
    assertThat(Floats.contains(new float[] {(float) -1}, (float) -1)).isTrue();
    assertThat(Floats.contains(ARRAY234, (float) 2)).isTrue();
    assertThat(Floats.contains(ARRAY234, (float) 3)).isTrue();

    assertThat(transpose).isEqualTo(expectedTranspose);
    assertThat(transpose(transpose)).isSameInstanceAs(directedGraph);
    AbstractNetworkTest.validateNetwork(transpose);

    assertThat(transpose.edgesConnecting(N1, N2)).isEmpty();
    assertThat(transpose.edgeConnecting(N1, N2).isPresent()).isFalse();
    assertThat(transpose.edgeConnectingOrNull(N1, N2)).isNull();

    assertThat(Chars.indexOf(ARRAY1, ARRAY234)).isEqualTo(-1);
    assertThat(Chars.indexOf(ARRAY1, ARRAY1)).isEqualTo(0);
    assertThat(Chars.indexOf(ARRAY234, ARRAY234)).isEqualTo(0);
    assertThat(Chars.indexOf(ARRAY234, new char[] {(char) 2, (char) 3})).isEqualTo(0);
    assertThat(Chars.indexOf(ARRAY234, new char[] {(char) 3, (char) 4})).isEqualTo(1);
    assertThat(Chars.indexOf(ARRAY234, new char[] {(char) 3})).isEqualTo(1);

  @Test
  public void hasCycle_emptyGraph() {
    assertThat(hasCycle(directedGraph)).isFalse();
    assertThat(hasCycle(undirectedGraph)).isFalse();
  }

  @Test
  public void hasCycle_isolatedNodes() {
    for (MutableGraph<Integer> graph : graphsToTest) {
      graph.addNode(1);
      graph.addNode(2);
    }
    assertThat(hasCycle(directedGraph)).isFalse();
    assertThat(hasCycle(undirectedGraph)).isFalse();
  }

  @Test

    assertThat(future.get()).isEqualTo("scheduleAtFixedRate");
    assertThat(recordedCommand).isSameInstanceAs(command);
    assertThat(recordedTimeUnit).isEqualTo(TimeUnit.NANOSECONDS);
    assertThat(Duration.ofNanos(recordedDelay)).isEqualTo(Duration.ofDays(2));
    assertThat(Duration.ofNanos(recordedInterval)).isEqualTo(Duration.ofHours(4));
  }