onMatch rule not triggering on subquery

[Michael Thomson]

Hi,

I suspect I am doing something wrong but it's not obvious to me and hoping
someone can spot what my issue is.

I am trying to add a simple filter after detection of LogicalTableScans on
particular tables

I have a rule that looks like this

public interface Config extends RelRule.Config {
    Config DEFAULT =
            EMPTY.withOperandSupplier(b0 ->
b0.operand(LogicalTableScan.class).anyInputs())
                    .as(Config.class);

    @Override
    default InjectFilterRule toRule() {
      return new InjectFilterRule(this, null);
    }
  }

Everything works as expected with most sql

but when using a subqueries like this

select * from t6  where t6.t1 in (select t1 from t6);

The result I see is

LogicalProject(t1=[$0], i1=[$1])
  LogicalFilter(condition=[IN($0, {
LogicalProject(t1=[$0])
  LogicalTableScan(table=[[database, t6]])
})])
    LogicalFilter(condition=[OR(=($0, 'a'), =($0, 'b'), =($0, 'c'))])
      LogicalTableScan(table=[[database, t6]])

You will note the bogus FILTER added to the first LogicalTableScan

LogicalFilter(condition=[OR(=($0, 'a'), =($0, 'b'), =($0, 'c'))])

but nothing was added to the one in the IN subquery

When I look in the debug it seems the onMatch code never receives an
invocation for the subquery Scan.

The rules are run as part of the planner.rel() call.

Any ideas of what I am overlooking or misunderstanding would be much
appreciated

thanks
Michael.