assertThat(ImmutableDoubleArray.of(0).isEmpty()).isFalse();
    assertThat(ImmutableDoubleArray.of(0, 1, 3).isEmpty()).isFalse();
    assertThat(ImmutableDoubleArray.of(0, 1, 3).subArray(1, 1).isEmpty()).isTrue();
    assertThat(ImmutableDoubleArray.of(0, 1, 3).subArray(1, 2).isEmpty()).isFalse();
  }

  public void testGet_good() {

    ImmutableSet<String> edges = ImmutableSet.copyOf(network.edges());
    assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isFalse();
    assertThat(network.edges()).containsExactlyElementsIn(edges);
    assertThat(networkAsMutableNetwork.addEdge(N2, N1, E12)).isFalse();
    assertThat(network.edges()).containsExactlyElementsIn(edges);
  }

  @Test
  public void addEdge_existingEdgeBetweenDifferentNodes() {

    Future<?> possiblyIgnoredError1 = serializer.submitAsync(thirdCallable, directExecutor());
    secondFuture.cancel(true);
    assertThat(secondCallable.called).isFalse();
    assertThat(thirdCallable.called).isFalse();
    firstFuture.set(null);
    assertThat(secondCallable.called).isFalse();
    assertThat(thirdCallable.called).isTrue();
  }

  public void testCancellationMultipleThreads() throws Exception {

    assertThat(ImmutableLongArray.of().isEmpty()).isTrue();
    assertThat(ImmutableLongArray.of(0).isEmpty()).isFalse();
    assertThat(ImmutableLongArray.of(0, 1, 3).isEmpty()).isFalse();
    assertThat(ImmutableLongArray.of(0, 1, 3).subArray(1, 1).isEmpty()).isTrue();
    assertThat(ImmutableLongArray.of(0, 1, 3).subArray(1, 2).isEmpty()).isFalse();
  }

  public void testGet_good() {
    ImmutableLongArray iia = ImmutableLongArray.of(0, 1, 3);

    assertThat(containsKey(cache, 654)).isFalse();
    assertThat(containsKey(cache, 2456)).isFalse();
    assertThat(containsKey(cache, 2)).isFalse();

    cache.put(654, 2675);
    cache.put(2456, 56);
    cache.put(2, 15);
    cache.put(1, 3);

    cache.invalidateAll(ImmutableSet.of(1, 2));

    assertThat(containsKey(cache, 1)).isFalse();
    assertThat(containsKey(cache, 2)).isFalse();

    CompactHashSet<Integer> set = CompactHashSet.create();
    assertThat(set.needsAllocArrays()).isTrue();
    assertThat(set.elements).isNull();

    set.add(1);
    assertThat(set.needsAllocArrays()).isFalse();
    assertThat(set.elements).hasLength(CompactHashing.DEFAULT_SIZE);
  }

  public void testAllocArraysExpectedSize() {
    for (int i = 0; i <= CompactHashing.DEFAULT_SIZE; i++) {

    assertThat(Buffer().writeByte(0x80).isProbablyUtf8(16L)).isTrue()
    assertThat(Buffer().writeByte(0x00).isProbablyUtf8(16L)).isFalse()
    assertThat(Buffer().writeByte(0xc0).isProbablyUtf8(16L)).isFalse()
  }

  @Test fun doesNotConsumeBuffer() {
    val buffer = Buffer()
    buffer.writeUtf8("hello ".repeat(1024))
    assertThat(buffer.isProbablyUtf8(100L)).isTrue()

    assume().that(graphIsMutable()).isTrue();

    addEdge(N1, N2, E12);
    ImmutableSet<String> edges = ImmutableSet.copyOf(network.edges());
    assertThat(networkAsMutableNetwork.addEdge(N1, N2, E12)).isFalse();
    assertThat(network.edges()).containsExactlyElementsIn(edges);
  }

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

      assertThat(cache.asMap().isEmpty()).isFalse();
      cache.invalidateAll();
      assertThat(cache.size()).isEqualTo(0);
      assertThat(cache.asMap().isEmpty()).isTrue();
      assertThat(cache.asMap().containsKey(key)).isFalse();
      assertThat(cache.asMap().containsValue(value)).isFalse();
    }
  }

  public void testKeySetEntrySetValues() {

    assertThat(stopwatch.elapsed(MILLISECONDS)).isIn(Range.closed(NOT_ENOUGH_MS, DELAY_MS * 2));
    // Is it still computing away anyway?
    assertThat(target.finished).isFalse();
    MILLISECONDS.sleep(ENOUGH_MS);
    assertThat(target.finished).isFalse();
  }

  public void testNewProxy_badMethodWithEnoughTime() throws Exception {
    SampleImpl target = new SampleImpl(DELAY_MS);