anchor.diff:    static final String ESC = "\u{1B}";
   
     String initial = '';
  -  String wrapped = '';
   
  -  ColorizeString([this.initial = '']) {
  -    wrapped = initial;
  -  }
  +  ColorizeString([this.initial = '']);
   
     String toString() {
  -    return wrapped;
  +    return initial;
     }
   
     ColorizeString noSuchMethod(Invocation mirror) {
  
positive.code:   }
  
    ColorizeString call(String text) {
      this.initial = text;
      this.wrapped = text;
      return this;
    }
  
    String buildEscSeq(String style) {
  
negative.code:   ColorizeString apply(String style, [String text]) {
  
      if (text == null) {
        text = initial;
      }
  
      initial = _stylize(style, text);
      return this;
  
    }
  
    String operator +(ColorizeString string) {
      return this.toString() + string.toString();
    }
  
    String _stylize(String style, String text) {
  