public static @Nullable ASTNode findSibling(ASTNode start, TokenSet types) {
    ASTNode child = start;
    while (true) {
      if (child == null) return null;
      if (types.contains(child.getElementType())) return child;
      child = child.getTreeNext();
    }
  }
public static @Nullable ASTNode findSibling(ASTNode start, TokenSet types)