presto-main/src/main/java/io/prestosql/sql/planner/planprinter/PlanPrinter.java/PlanPrinter/visitUnnest
class PlanPrinter:        @Override
        public Void visitUnnest(UnnestNode node, Void context)
        {
            String name;
            if (node.getFilter().isPresent()) {
                name = node.getJoinType().getJoinLabel() + " Unnest";
            }
            else if (!node.getReplicateSymbols().isEmpty()) {
                name = "CrossJoin Unnest";
            }
            else {
                name = "Unnest";
            }
            addNode(
                    node,
                    name,
                    format("[replicate=%s, unnest=%s", formatOutputs(types, node.getReplicateSymbols()), formatOutputs(types, node.getUnnestSymbols().keySet()))
                            + (node.getFilter().isPresent() ? format(", filter=%s]", node.getFilter().get().toString()) : "]"));
            return processChildren(node, context);
        }