}

  @Override
  protected boolean doEquivalent(Iterable<T> iterableA, Iterable<T> iterableB) {
    Iterator<T> iteratorA = iterableA.iterator();
    Iterator<T> iteratorB = iterableB.iterator();

    while (iteratorA.hasNext() && iteratorB.hasNext()) {
      if (!elementEquivalence.equivalent(iteratorA.next(), iteratorB.next())) {
        return false;
      }
    }

    StringBuilder builder = new StringBuilder();
    Iterator<String> iterator = splitter.split(builder).iterator();

    builder.append("A,");
    assertThat(iterator.next()).isEqualTo("A");
    builder.append("B,");
    assertThat(iterator.next()).isEqualTo("B");
    builder.append("C");
    assertThat(iterator.next()).isEqualTo("C");
    assertFalse(iterator.hasNext());
  }

  public void testCopyOf_iterator_empty() {
    Iterator<String> iterator = emptyIterator();
    Set<String> set = copyOf(iterator);
    assertEquals(Collections.<String>emptySet(), set);
    assertThat(set).isSameInstanceAs(this.<String>of());
  }

  public void testCopyOf_iterator_oneElement() {
    Iterator<String> iterator = singletonIterator("a");
    Set<String> set = copyOf(iterator);
    assertEquals(singleton("a"), set);
  }

     */
    public IteratorEnumeration(final Iterator<T> iterator) {
        assertArgumentNotNull("iterator", iterator);
        this.iterator = iterator;
    }

    /**
     * Creates an {@link IteratorEnumeration}.
     *
     * @param iterable the iterable object (must not be {@literal null})
     */
    public IteratorEnumeration(final Iterable<T> iterable) {

        }
      }
      return true;
    } else {
      return elementsEqual(thisList.iterator(), otherList.iterator());
    }
  }

  /** An implementation of {@link List#addAll(int, Collection)}. */
  static <E extends @Nullable Object> boolean addAllImpl(
      List<E> list, int index, Iterable<? extends E> elements) {
    boolean changed = false;

  }

  public void testSize1() {
    Iterator<Integer> iterator = singleton(0).iterator();
    assertEquals(1, Iterators.size(iterator));
  }

  public void testSize_partiallyConsumed() {
    Iterator<Integer> iterator = asList(1, 2, 3, 4, 5).iterator();
    iterator.next();
    iterator.next();
    assertEquals(3, Iterators.size(iterator));
  }

    return (MinimalIterable) of(elements.toArray());
  }

  private @Nullable Iterator<E> iterator;

  private MinimalIterable(Iterator<E> iterator) {
    this.iterator = iterator;
  }

  @Override
  public Iterator<E> iterator() {
    if (iterator == null) {
      // TODO: throw something else? Do we worry that people's code and tests

   *
   * <p>Note: The input {@code Iterator} will be copied to an {@code ImmutableList} when this method
   * is called. This will fail if the iterator is infinite and may cause problems if the iterator
   * eagerly fetches data for each source when iterated (rather than producing sources that only
   * load data through their streams). Prefer using the {@link #concat(Iterable)} overload if
   * possible.
   *

      TestSubjectGenerator<? extends Iterable<E>> collectionGenerator) {
    this.collectionGenerator = collectionGenerator;
  }

  @Override
  public TestSubjectGenerator<? extends Iterable<E>> getInnerGenerator() {
    return collectionGenerator;
  }

  @Override
  public Iterator<E> get() {
    return collectionGenerator.createTestSubject().iterator();
  }

    return singletonMap(key, value).entrySet().iterator().next();
  }

  private static boolean isEmpty(Iterable<?> iterable) {
    return iterable instanceof Collection
        ? ((Collection<?>) iterable).isEmpty()
        : !iterable.iterator().hasNext();
  }

  public static void assertEmpty(Iterable<?> iterable) {
    if (!isEmpty(iterable)) {
      fail("Not true that " + iterable + " is empty");
    }
  }