[CAY-2779] "Nullify" delete rules is not processed with n:m and inheritance hierarchy

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 4.2.RC1
• Fix Version/s: 5.0-M2
• Assignee: Nikita Timofeev
• Reporter: Andrus Adamchik
• Created: 22/Nov/22 13:56
• Updated: 09/Aug/24 10:18

Description

A model the same as the one in CAY-2777:

// a table with a many to many to self
T1: id, type
T11: child_id, parent_id; 

// Base ObjEntity
O1: 
  - flat rel "parents" mapped as "db:parents.parent"

// Sub ObjEntity 1
O1S1:
  - flat rel "children" mapped as "db:children.child"

// Sub ObjEntity 2
O1S2:

n:m has "Nullify" delete rule on both ends. When deleting a child, the child is not removed from parent's children, because the code gets confused about the inheritance hierarchy. Specifically here inside ObjectContextDeleteAction, "reverseArc" is null, whereas it should be "O1S1.children" :

case DeleteRule.NULLIFY:
    ArcProperty reverseArc = property.getComplimentaryReverseArc();

    if (reverseArc == null) {
        // nothing we can do here
        break;
    }

Oddly enough, it still generated a correct DB operation, deleting the join table record, because of the hardcoded flattened relationship processing block just a few lines prior the one mentioned above.

These two things are still incorrect:

• Parent object still has a child in its collection
• "nodeRemoved" graph operation is not recorded, so any listener flows that depend on it do not work.