presto-main/src/main/java/io/prestosql/sql/planner/sanity/ValidateDependenciesChecker.java/Visitor/visitLimit
class Visitor:        @Override
        public Void visitLimit(LimitNode node, Set<Symbol> boundSymbols)
        {
            PlanNode source = node.getSource();
            source.accept(this, boundSymbols); // visit child

            return null;
        }