anchor.diff:  @CustomTag('spark-splitter')
   class SparkSplitter extends SparkWidget {
     static const _MIN_DRAGGABLE_SIZE = 6;
  -  
  +
     /// Possible values are "left", "right", "up" and "down".
     /// The direction specifies:
     /// 1) whether the split is horizontal or vertical;
  
positive.code:     }
    }
  
    /// Cache the current actual size of the target.
    void _cacheTargetSize() {
      final style = _target.getComputedStyle();
      final sizeStr = _isHorizontal ? style.height : style.width;
      _targetSize = int.parse(_sizeRe.firstMatch(sizeStr).group(1));
    }
  
    /// Update the cached and the actual size of the target.
  
negative.code:     _targetSize += (_isTargetNextSibling ? -delta : delta);
      _targetSize = _targetSize.clamp(minTargetSize, maxTargetSize);
      _commitTargetSize(_targetSize);
    }
  
    /// When dragging starts, cache the target's size and temporarily subscribe
  