While working on SERVER-72416, I've noticed that the or_to_in.js is breaking when there is a collection level collation and no collation for the query. This is likely because the re-write logic is not handling re-writes properly and the assertions in the or_to_in.js are incorrect. I've also noticed that this and this assertions are not doing anything, as they both generate the undefined value. The path for parsedQuery is plan.queryPlanner.parsedQuery. We should also fix this assertion after figuring out the expected correct behavior. ian.boros@mongodb.com pointed out that regex should not be collation aware. So we should probably disable all string and regex combination re-writes.