@NotNull
  @Override
  protected DirDiffOperation getOperation(DirDiffElementImpl element) {
    if (element.isSource()) {
      return DirDiffOperation.DELETE;
    }
    else {
      return DirDiffOperation.COPY_FROM;
    }
  }
@NotNull
  @Override
  protected DirDiffOperation getOperation(DirDiffElementImpl element)