@NotNull
  private Type calcType() {
    if (myBeforeRevision == null) return Type.NEW;
    if (myAfterRevision == null) return Type.DELETED;

    FilePath bFile = myBeforeRevision.getFile();
    FilePath aFile = myAfterRevision.getFile();
    if (!Comparing.equal(bFile, aFile)) return Type.MOVED;

    // enforce case-sensitive check
    if (!SystemInfo.isFileSystemCaseSensitive) {
      String bPath = bFile.getPath();
      String aPath = aFile.getPath();
      if (!bPath.equals(aPath) && bPath.equalsIgnoreCase(aPath)) return Type.MOVED;
    }

    return Type.MODIFICATION;
  }
@NotNull
  private Type calcType()