@Override
  protected void doRevert() {
    Block b = myCalculator.getSelectionFor(myTargetRevisionId, Progress.EMPTY);

    Document d = myGateway.getDocument(myTargetPath);

    int from = d.getLineStartOffset(myFromLine);
    int to = d.getLineEndOffset(myToLine);

    d.replaceString(from, to, b.getBlockContent());
  }
@Override
  protected void doRevert()