public static @Nullable ASTNode getPreviousNonWhitespaceSibling(@Nullable ASTNode node) {
    ASTNode prevNode = node == null ? null : node.getTreePrev();
    while (prevNode != null && isWhitespaceOrEmpty(prevNode)) {
      prevNode = prevNode.getTreePrev();
    }
    return prevNode;
  }
public static @Nullable ASTNode getPreviousNonWhitespaceSibling(@Nullable ASTNode node)