code: @Override
    public Void visitDoWhileLoop(DoWhileLoopTree node, Context context) {
      scan(node.getStatement(), context);
      scan(SKIP_PARENS.visit(node.getCondition(), null), context);
      return null;
    }
docs: /*
  Matching on the parentheses surrounding the condition of an if, while, or do-while
  is nonsensical, as those parentheses are obligatory and should never be changed.