presto-main/src/main/java/io/prestosql/sql/planner/iterative/rule/TransformCorrelatedSingleRowSubqueryToProject.java/TransformCorrelatedSingleRowSubqueryToProject/projectNode
class TransformCorrelatedSingleRowSubqueryToProject:    private ProjectNode projectNode(PlanNode source, Assignments assignments, Context context)
    {
        return new ProjectNode(context.getIdAllocator().getNextId(), source, assignments);
    }