private void removeMapping(@NotNull MappedRange mapping) {
      RangeMarker rangeMarker = mapping.range;
      if (rangeMarker.isValid()) {
        int start = rangeMarker.getStartOffset();
        int end = rangeMarker.getEndOffset();
        assert doc == rangeMarker.getDocument();
        doc.deleteString(start - mySeparator.length(), end);
        rangeMarker.dispose();
      }
    }
private void removeMapping(@NotNull MappedRange mapping)