* surprising behavior of {@code toUpperCase()} and {@code toLowerCase()}.
   *
   * @since 16.0
   */
  public static boolean equalsIgnoreCase(CharSequence s1, CharSequence s2) {
    // Calling length() is the null pointer check (so do it before we can exit early).
    int length = s1.length();
    if (s1 == s2) {
      return true;
    }
    if (length != s2.length()) {

     * tolerance is implemented differently: Its implementation avoids calling this toString(Object)
     * method in the first place.)
     */
    requireNonNull(part);
    return (part instanceof CharSequence) ? (CharSequence) part : part.toString();
  }

  private static Iterable<@Nullable Object> iterable(
      @Nullable Object first, @Nullable Object second, @Nullable Object[] rest) {
    checkNotNull(rest);

   * time and space.
   *
   * @throws IllegalArgumentException if {@code sequence} contains ill-formed UTF-16 (unpaired
   *     surrogates)
   */
  public static int encodedLength(CharSequence sequence) {
    // Warning to maintainers: this implementation is highly optimized.
    int utf16Length = sequence.length();
    int utf8Length = utf16Length;
    int i = 0;

    // This loop optimizes for pure ASCII.

  }

  public void testGetGenericSuperclass_wildcard_boundIsInterface() {
    assertNull(TypeToken.of(Types.subtypeOf(CharSequence.class)).getGenericSuperclass());
    assertEquals(
        new TypeToken<CharSequence[]>() {},
        TypeToken.of(Types.subtypeOf(CharSequence[].class)).getGenericSuperclass());
  }

  public <T> void testGetGenericInterfaces_typeVariable_unbounded() {

  }

  @GwtIncompatible // ObjectArrays.concat(Object[], Object[], Class)
  public void testConcatWithMoreGeneralType() {
    CharSequence[] result = ObjectArrays.concat(new String[0], new String[0], CharSequence.class);
    assertEquals(CharSequence[].class, result.getClass());
  }

  public void testToArrayImpl1() {
    doTestToArrayImpl1(new ArrayList<Integer>());

    }

    private static boolean isEmpty(Object value) {
      // Put types estimated to be the most frequent first.
      if (value instanceof CharSequence) {
        return ((CharSequence) value).length() == 0;
      } else if (value instanceof Collection) {
        return ((Collection<?>) value).isEmpty();
      } else if (value instanceof Map) {

HSPLkotlin/text/StringsKt__StringsKt;->contains$default(Ljava/lang/CharSequence;CZI)Z
HSPLkotlin/text/StringsKt__StringsKt;->contains$default(Ljava/lang/CharSequence;Ljava/lang/CharSequence;ZI)Z
HSPLkotlin/text/StringsKt__StringsKt;->endsWith$default(Ljava/lang/CharSequence;CZI)Z
HSPLkotlin/text/StringsKt__StringsKt;->getLastIndex(Ljava/lang/CharSequence;)I
HSPLkotlin/text/StringsKt__StringsKt;->indexOf$default(Ljava/lang/CharSequence;CIZI)I

  static final int SAMPLES = 0x100;
  static final int SAMPLE_MASK = 0xFF;

  /**
   * Compute arrays of valid unicode text, and store it in 3 forms: byte arrays, Strings, and
   * StringBuilders (in a CharSequence[] to make it a little harder for the JVM).
   */
  @BeforeExperiment
  void setUp() {
    long seed = 99;
    Random rnd = new Random(seed);
    strings = new String[SAMPLES];

  public void testContainsPattern_apply() {
    Predicate<CharSequence> isFoobar = Predicates.containsPattern("^Fo.*o.*bar$");
    assertTrue(isFoobar.apply("Foxyzoabcbar"));
    assertFalse(isFoobar.apply("Foobarx"));
  }

  @GwtIncompatible // Predicates.containsPattern
  public void testContains_apply() {
    Predicate<CharSequence> isFoobar = Predicates.contains(Pattern.compile("^Fo.*o.*bar$"));

   *
   * <p><b>Note:</b> When implementing an escaper it is a good idea to override this method for
   * efficiency by inlining the implementation of {@link #nextEscapeIndex(CharSequence, int, int)}
   * directly. Doing this for {@link com.google.common.net.PercentEscaper} more than doubled the
   * performance for unescaped strings (as measured by {@code CharEscapersBenchmark}).
   *