assertEquals(s.length(), matcher.countIn(s));
  }

  // Kotlin subSequence()/replace() always return new strings, violating expectations of this test
  @J2ktIncompatible
  public void testGeneral() {
    doTestGeneral(is('a'), 'a', 'b');
    doTestGeneral(isNot('a'), 'b', 'a');
    doTestGeneral(anyOf("x"), 'x', 'z');
    doTestGeneral(anyOf("xy"), 'y', 'z');
    doTestGeneral(anyOf("CharMatcher"), 'C', 'z');