* @throws Exception
     */
    @Test
    public void testGetLast() throws Exception {
        try {
            list.getLast();
            fail();
        } catch (final NoSuchElementException ex) {
            System.out.println(ex);
        }
        list.addLast("1");
        assertThat(list.getLast(), is("1"));
    }

    /**
     * @throws Exception
     */
    @Test

  }

  @Override
  @ParametricNullness
  public E getFirst() {
    return delegate().getFirst();
  }

  @Override
  @ParametricNullness
  public E getLast() {
    return delegate().getLast();
  }

  @CanIgnoreReturnValue // TODO(cpovirk): Consider removing this?
  @Override
  public boolean offerFirst(@ParametricNullness E e) {
    return delegate().offerFirst(e);
  }

    }

    @Override
    public E getFirst() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.getFirst();
    }

    @Override
    public E getLast() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.getLast();
    }

    @Override
    public @Nullable E peekFirst() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.peekFirst();
    }

    }

    @Override
    public E getFirst() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.getFirst();
    }

    @Override
    public E getLast() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.getLast();
    }

    @Override
    public @Nullable E peekFirst() {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.peekFirst();
    }

        this.document = document;
        stack.addFirst(document.createElement("root"));
    }

    List<Element> getElements() {
        List<Element> elements = new ArrayList<Element>();
        for (Node node = stack.getLast().getFirstChild(); node != null; node = node.getNextSibling()) {
            elements.add((Element) node);
        }
        return elements;
    }

    public void appendChild(String text) {

        "addAll(n, allPresent) should return true",
        getList().addAll(0, MinimalCollection.of(e0())));
    expectAdded(0, e0());
  }

  @ListFeature.Require(absent = SUPPORTS_ADD_WITH_INDEX)
  @CollectionSize.Require(absent = ZERO)
  public void testAddAllAtIndex_unsupportedAllPresent() {
    assertThrows(
        UnsupportedOperationException.class, () -> getList().addAll(0, MinimalCollection.of(e0())));
    expectUnchanged();
  }

   */
  public void testAddAtIndex_unsupportedPresent() {
    assertThrows(UnsupportedOperationException.class, () -> getList().add(0, e0()));
    expectUnchanged();
  }

  @ListFeature.Require(SUPPORTS_ADD_WITH_INDEX)
  public void testAddAtIndex_supportedNotPresent() {
    getList().add(0, e3());
    expectAdded(0, e3());
  }

  @CollectionFeature.Require(FAILS_FAST_ON_CONCURRENT_MODIFICATION)

    int index = aValidIndex();
    E initialValue = getList().get(index);
    assertEquals(
        "set(i, x) should return the old element at position i.",
        initialValue,
        getList().set(index, newValue));
    assertEquals("After set(i, x), get(i) should return x", newValue, getList().get(index));
    assertEquals("set() should not change the size of a list.", getNumElements(), getList().size());
  }

    assertEquals("::1", HostAndPort.fromString("[::1]:80").requireBracketsForIPv6().getHost());
    // Non-bracketed non-IPv6 works fine.
    assertEquals("x", HostAndPort.fromString("x").requireBracketsForIPv6().getHost());
    assertEquals("x", HostAndPort.fromString("x:80").requireBracketsForIPv6().getHost());

    // Non-bracketed IPv6 fails.
    assertThrows(

  public void testRemoveAtIndex_unsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getList().remove(0));
    expectUnchanged();
  }

  @ListFeature.Require(SUPPORTS_REMOVE_WITH_INDEX)
  public void testRemoveAtIndex_negative() {
    assertThrows(IndexOutOfBoundsException.class, () -> getList().remove(-1));
    expectUnchanged();
  }

  @ListFeature.Require(SUPPORTS_REMOVE_WITH_INDEX)