assertEquals("foo", LOWER_CAMEL.to(LOWER_UNDERSCORE, "foo"));
    assertEquals("foo_bar", LOWER_CAMEL.to(LOWER_UNDERSCORE, "fooBar"));
    assertEquals("h_t_t_p", LOWER_CAMEL.to(LOWER_UNDERSCORE, "hTTP"));
  }

  public void testLowerCamelToLowerCamel() {
    assertEquals("foo", LOWER_CAMEL.to(LOWER_CAMEL, "foo"));
    assertEquals("fooBar", LOWER_CAMEL.to(LOWER_CAMEL, "fooBar"));
  }

  private static final String LOWER = "abcdefghijklmnopqrstuvwxyz";
  private static final String UPPER = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

  public void testToLowerCase() {
    assertEquals(LOWER, Ascii.toLowerCase(UPPER));
    assertSame(LOWER, Ascii.toLowerCase(LOWER));
    assertEquals(IGNORED, Ascii.toLowerCase(IGNORED));

  public Iterator<E> iterator() {
    return delegate.iterator();
  }

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

  @Override
  public @Nullable E lower(E e) {
    return delegate.lower(checkValid(e));
  }

  @Override
  public @Nullable E pollFirst() {
    return delegate.pollFirst();
  }

  @Override
  public @Nullable E pollLast() {

    }

    @Override
    public SortedSet<T> subSet(T fromElement, T toElement) {
      return standardSubSet(fromElement, toElement);
    }

    @Override
    public @Nullable T lower(T e) {
      return standardLower(e);
    }

    @Override
    public @Nullable T floor(T e) {
      return standardFloor(e);
    }

    @Override
    public @Nullable T ceiling(T e) {

  }

  @Override
  public E last() {
    if (isEmpty()) {
      throw new NoSuchElementException();
    }
    return elements.get(size() - 1);
  }

  @Override
  @CheckForNull
  public E lower(E element) {
    int index = headIndex(element, false) - 1;
    return (index == -1) ? null : elements.get(index);
  }

  @Override
  @CheckForNull
  public E floor(E element) {

    assertEquals("foo", LOWER_CAMEL.to(LOWER_UNDERSCORE, "foo"));
    assertEquals("foo_bar", LOWER_CAMEL.to(LOWER_UNDERSCORE, "fooBar"));
    assertEquals("h_t_t_p", LOWER_CAMEL.to(LOWER_UNDERSCORE, "hTTP"));
  }

  public void testLowerCamelToLowerCamel() {
    assertEquals("foo", LOWER_CAMEL.to(LOWER_CAMEL, "foo"));
    assertEquals("fooBar", LOWER_CAMEL.to(LOWER_CAMEL, "fooBar"));
  }

@ElementTypesAreNonnullByDefault
public enum CaseFormat {
  /** Hyphenated variable naming convention, e.g., "lower-hyphen". */
  LOWER_HYPHEN(CharMatcher.is('-'), "-") {
    @Override
    String normalizeWord(String word) {
      return Ascii.toLowerCase(word);
    }

    @Override
    String convert(CaseFormat format, String s) {
      if (format == LOWER_UNDERSCORE) {
        return s.replace('-', '_');
      }

    StringBuilder builder = new StringBuilder();
    Writer writer = new AppendableWriter(builder);

    writer.write("Hello".toCharArray());
    writer.write(',');
    writer.write(0xBEEF0020); // only lower 16 bits are important
    writer.write("Wo");
    writer.write("Whirled".toCharArray(), 3, 2);
    writer.write("Mad! Mad, I say", 2, 2);

    assertEquals("Hello, World!", builder.toString());
  }

     * the uniformly-distributed random integer, then truncates any fractional
     * part, so higher integers would appear (in this case linearly) more often
     * than lower ones.
     */
    return (int) Math.pow(a, 1.0 / concentration);
  }

  @AfterExperiment
  void tearDown() {
    double req = requests.get();
    double hit = req - misses.get();

    return RANDOM_SOURCE.nextBoolean() ? result : result.negate();
  }

  /**
   * Chooses a number in (-2^numBits, 2^numBits) at random, with density concentrated in numbers of
   * lower magnitude.
   */
  static BigInteger randomBigInteger(int numBits) {
    while (true) {
      if (RANDOM_SOURCE.nextBoolean()) {
        return randomNonNegativeBigInteger(numBits);
      }