assertThrows(
            IllegalArgumentException.class, () -> networkAsMutableNetwork.addEdge(N4, N5, E12));
    assertThat(e).hasMessageThat().contains(ERROR_REUSE_EDGE);
    e = assertThrows(IllegalArgumentException.class, () -> addEdge(N2, N1, E12));
    assertThat(e).hasMessageThat().contains(ERROR_REUSE_EDGE);
  }

  @Test
  public void addEdge_parallelEdge_notAllowed() {
    assume().that(graphIsMutable()).isTrue();

        assertThrows(
            IllegalArgumentException.class, () -> networkAsMutableNetwork.addEdge(N4, N5, E12));
    assertThat(e).hasMessageThat().contains(ERROR_REUSE_EDGE);
    e = assertThrows(IllegalArgumentException.class, () -> addEdge(N2, N1, E12));
    assertThat(e).hasMessageThat().contains(ERROR_REUSE_EDGE);
  }

  @Test
  public void addEdge_parallelEdge_notAllowed() {
    assume().that(graphIsMutable()).isTrue();

            () -> networkAsMutableNetwork.addEdge(N1, N2, EDGE_NOT_IN_GRAPH));
    assertThat(e).hasMessageThat().contains(ERROR_PARALLEL_EDGE);
    e =
        assertThrows(
            IllegalArgumentException.class,
            () -> networkAsMutableNetwork.addEdge(N2, N1, EDGE_NOT_IN_GRAPH));
    assertThat(e).hasMessageThat().contains(ERROR_PARALLEL_EDGE);
  }

  @Test

    assertThat(throwable).isInstanceOf(clazz);
    if (params.length == 1) {
      assertThat(throwable).hasMessageThat().isNull();
    } else if (params.length == 2) {
      assertThat(throwable).hasMessageThat().isEmpty();
    } else {
      assertThat(throwable)
          .hasMessageThat()
          .isEqualTo(Strings.lenientFormat("", Arrays.copyOfRange(params, 2, params.length)));
    }
  }

  /**

    assertThat(throwable).isInstanceOf(clazz);
    if (params.length == 1) {
      assertThat(throwable).hasMessageThat().isNull();
    } else if (params.length == 2) {
      assertThat(throwable).hasMessageThat().isEmpty();
    } else {
      assertThat(throwable)
          .hasMessageThat()
          .isEqualTo(Strings.lenientFormat("", Arrays.copyOfRange(params, 2, params.length)));
    }
  }

  /**

        assertThrows(IllegalArgumentException.class, () -> range.intersection(Range.open(3, 5)));
    assertThat(expected).hasMessageThat().contains("connected");
    expected =
        assertThrows(IllegalArgumentException.class, () -> range.intersection(Range.closed(0, 2)));
    assertThat(expected).hasMessageThat().contains("connected");
  }

  public void testIntersection_deFactoEmpty() {
    {

        assertThrows(IllegalStateException.class, () -> service.awaitRunning());
    assertThat(expected).hasCauseThat().hasMessageThat().isEqualTo("kaboom!");
    executionThread.join();

    assertTrue(service.startUpCalled);
    assertEquals(Service.State.FAILED, service.state());
    assertThat(service.failureCause()).hasMessageThat().isEqualTo("kaboom!");
  }

  private class ThrowOnStartUpService extends AbstractExecutionThreadService {

        assertThrows(IllegalArgumentException.class, () -> range.intersection(Range.open(3, 5)));
    assertThat(expected).hasMessageThat().contains("connected");
    expected =
        assertThrows(IllegalArgumentException.class, () -> range.intersection(Range.closed(0, 2)));
    assertThat(expected).hasMessageThat().contains("connected");
  }

  public void testIntersection_deFactoEmpty() {
    {

        assertThrows(IllegalArgumentException.class, () -> directedGraph.addEdge(N1, N2, E12_A));
    assertThat(e).hasMessageThat().contains(ERROR_PARALLEL_EDGE);

    // By default, self-loop edges are not allowed.
    e = assertThrows(IllegalArgumentException.class, () -> directedGraph.addEdge(N1, N1, E11));
    assertThat(e).hasMessageThat().contains(ERROR_SELF_LOOP);
  }

  @Test
  public void createUndirected() {

    assertThat(e)
        .hasMessageThat()
        .contains("Expected to be healthy after starting. The following services are not running:");

    Throwable[] suppressed = e.getSuppressed();
    assertThat(suppressed).hasLength(2);
    assertThat(suppressed[0]).hasCauseThat().isInstanceOf(IllegalStateException.class);
    assertThat(suppressed[0]).hasCauseThat().hasMessageThat().isEqualTo("run failure");