* built-in nullness feature?
       */
      "ExtendsObject",
    })
    <T extends Object> void withObjectBound(List<T> list) {}

    @SuppressWarnings("unused")
    <T extends Number & CharSequence> void withUpperBound(List<T> list) {}

    static TypeVariable<?> getTypeVariable(String methodName) throws Exception {
      ParameterizedType parameterType =
          (ParameterizedType)

      checkPositionIndexes(off, off + len, str.length());
    }

    @Override
    public Writer append(@CheckForNull CharSequence csq) {
      return this;
    }

    @Override
    public Writer append(@CheckForNull CharSequence csq, int start, int end) {
      checkPositionIndexes(start, end, csq == null ? "null".length() : csq.length());
      return this;
    }

    @Override

        flushAttributes();
        builder.append(value);
        return this;
    }

    public Ansi a(CharSequence value, int start, int end) {
        flushAttributes();
        builder.append(value, start, end);
        return this;
    }

    public Ansi a(CharSequence value) {
        flushAttributes();
        builder.append(value);
        return this;
    }

        next(1);
    }

    public void next(int n) {
        pos += n;
    }

    public boolean lookingAt(char c) {
        return input.charAt(pos) == c;
    }

    public boolean lookingAt(CharSequence prefix) {
        int i = 0;
        int cpos = pos;
        while (i < prefix.length() && cpos < input.length()) {
            if (prefix.charAt(i) != input.charAt(cpos)) {
                return false;
            }

  public void testRepeat_null() {
    assertThrows(NullPointerException.class, () -> Strings.repeat(null, 5));
  }

  @SuppressWarnings("UnnecessaryStringBuilder") // We want to test a non-String CharSequence
  public void testCommonPrefix() {
    assertEquals("", Strings.commonPrefix("", ""));
    assertEquals("", Strings.commonPrefix("abc", ""));
    assertEquals("", Strings.commonPrefix("", "abc"));

  public void testRepeat_null() {
    assertThrows(NullPointerException.class, () -> Strings.repeat(null, 5));
  }

  @SuppressWarnings("UnnecessaryStringBuilder") // We want to test a non-String CharSequence
  public void testCommonPrefix() {
    assertEquals("", Strings.commonPrefix("", ""));
    assertEquals("", Strings.commonPrefix("abc", ""));
    assertEquals("", Strings.commonPrefix("", "abc"));

  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() {
    final long seed = 99;
    final Random rnd = new Random(seed);
    strings = new String[SAMPLES];

  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() {
    final long seed = 99;
    final Random rnd = new Random(seed);
    strings = new String[SAMPLES];

  private final Pattern pattern;

  JdkPattern(Pattern pattern) {
    this.pattern = Preconditions.checkNotNull(pattern);
  }

  @Override
  public CommonMatcher matcher(CharSequence t) {
    return new JdkMatcher(pattern.matcher(t));
  }

  @Override
  public String pattern() {
    return pattern.pattern();
  }

  @Override
  public int flags() {
    return pattern.flags();

          }
          // Inefficient implementation that defines all letters as escapable.
          @Override
          protected int nextEscapeIndex(CharSequence csq, int index, int end) {
            while (index < end && !Character.isLetter(csq.charAt(index))) {
              index++;
            }
            return index;
          }
        };