}

  /**
   * Copies an iterator's elements into an array. The iterator will be left exhausted: its {@code
   * hasNext()} method will return {@code false}.
   *
   * @param iterator the iterator to copy
   * @param type the type of the elements
   * @return a newly-allocated array into which all the elements of the iterator have been copied
   */
  @GwtIncompatible // Array.newInstance(Class, int)

  }

  public void testOf_empty() {
    assertEquals(ImmutableList.of(), Lists.newArrayList(FluentIterable.of()));
  }

  // Exhaustive tests are in IteratorsTest. These are copied from IterablesTest.
  public void testConcatIterable() {
    List<Integer> list1 = newArrayList(1);
    List<Integer> list2 = newArrayList(4);

    List<List<Integer>> input = newArrayList(list1, list2);

  }

  /**
   * {@inheritDoc}
   *
   * <p><b>Note:</b> This tests exact equality of the calculated statistics, including the floating
   * point values. Two instances are guaranteed to be considered equal if one is copied from the
   * other using {@code second = new StatsAccumulator().addAll(first).snapshot()}, if both were
   * obtained by calling {@code snapshot()} on the same {@link StatsAccumulator} without adding any

    assertThat(newFirst.getValue()).isEqualTo(valueThree);
    assertEquals(hashThree, newFirst.getHash());
    assertThat(newFirst.getNext()).isEqualTo(entryOne);

    // tail (remaining entries are copied in reverse order)
    newFirst = segment.removeFromChainForTesting(entryThree, entryOne);
    assertThat(newFirst.getKey()).isEqualTo(keyTwo);
    assertThat(newFirst.getValue()).isEqualTo(valueTwo);

    assertThat(newFirst.getValue()).isEqualTo(valueThree);
    assertEquals(hashThree, newFirst.getHash());
    assertThat(newFirst.getNext()).isEqualTo(entryOne);

    // tail (remaining entries are copied in reverse order)
    newFirst = segment.removeFromChainForTesting(entryThree, entryOne);
    assertThat(newFirst.getKey()).isEqualTo(keyTwo);
    assertThat(newFirst.getValue()).isEqualTo(valueTwo);

  }

  // Verify that stack traces of func is copied to graph function library.
  ASSERT_NE(func_stack_traces, nullptr);
  EXPECT_EQ(func_stack_traces->size(), 4);
  EXPECT_EQ(func_stack_traces->at("neg")->ToString({}), kNegStackToString);
  EXPECT_EQ(func_stack_traces->at("feed")->ToString({}), kFeedStackToString);

  // Verify that stack traces of grad_func is copied to graph function library.

  }

  /**
   * Returns an array containing each value of {@code collection}, converted to a {@code float}
   * value in the manner of {@link Number#floatValue}.
   *
   * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Number} instances

   * @return a newly-allocated array into which all the elements of this fluent iterable have been
   *     copied
   */
  @GwtIncompatible // Array.newArray(Class, int)
  public final E[] toArray(Class<@NonNull E> type) {
    return Iterables.<E>toArray(getDelegate(), type);
  }

  /**
   * Copies all the elements from this fluent iterable to {@code collection}. This is equivalent to

   * @return a newly-allocated array into which all the elements of this fluent iterable have been
   *     copied
   */
  @GwtIncompatible // Array.newArray(Class, int)
  public final E[] toArray(Class<@NonNull E> type) {
    return Iterables.<E>toArray(getDelegate(), type);
  }

  /**
   * Copies all the elements from this fluent iterable to {@code collection}. This is equivalent to

  }

  /**
   * Returns an array containing each value of {@code collection}, converted to a {@code int} value
   * in the manner of {@link Number#intValue}.
   *
   * <p>Elements are copied from the argument collection as if by {@code collection.toArray()}.
   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Number} instances