Crash during batch deletion merge when positive fractional decimals are stored and used in a derived attribute

I am experiencing a crash when performing a batch delete and merging changes on a Core Data store that uses NSPersistentCloudKitContainer. The crash appears to be triggered when positive fractional Decimal values are stored in a TransactionSplit entity (those values are aggregated via a derived attribute in the AccountTransaction entity). If I store whole numbers or negative fractional decimals, deletion seems to work correctly. I suspect that the issue is related to the internal representation of positive fractional decimals in conjunction with a derived attribute.

Data Model Setup:

• Account (1:N relationship → AccountTransaction)
• AccountTransaction (1:N relationship → TransactionSplit), which contains a derived attribute (e.g., “splits.amount.@sum”) that computes the sum over the “amount” attribute on its related TransactionSplit objects.
• TransactionSplit, which contains a stored Decimal attribute named “amount” (of type Decimal/NSDecimalNumber).

Steps to Reproduce:

1. Insert sample data where each TransactionSplit’s “amount” is set to a positive fractional value (e.g., 1000.01), by using code similar to:

func createSampleData() {
  // Execute all creation on the context’s queue.
  let checkingAccount = Account(context: context)
  checkingAccount.id = UUID()
  checkingAccount.name = "Main Checking"
  let randomTransactionCount = 1000
  for _ in 0..<randomTransactionCount {
    let transaction = AccountTransaction(context: context)
transaction.id = UUID()
    transaction.account = checkingAccount
    let randomValue = Double.random(in: 5...5000)
    let decimalValue = NSDecimalNumber(value: randomValue)

    let split1 = TransactionSplit(context: context)
    split1.id = UUID()
    split1.amount = decimalValue
    split1.transaction = transaction

    let split2 = TransactionSplit(context: context)
    split2.id = UUID() 
    split2.amount = decimalValue
    split2.transaction = transaction
  }
  save()
}

1. The AccountTransaction’s derived attribute automatically aggregates the sum of its related TransactionSplit amounts.
2. Perform a batch deletion using NSBatchDeleteRequest (with resultType set to .resultTypeObjectIDs) on your entities and merge the changes back into your main context:

private func delete(_ fetchRequest: NSFetchRequest<NSFetchRequestResult>) {
  let batchDeleteRequest = NSBatchDeleteRequest(fetchRequest: fetchRequest)
  batchDeleteRequest.resultType = .resultTypeObjectIDs

  // ⚠️ When performing a batch delete we need to make sure we read the result back
  // then merge all the changes from that result back into our live view context
  // so that the two stay in sync.
  if let delete = try? context.execute(batchDeleteRequest) as? NSBatchDeleteResult {
    let changes = [NSDeletedObjectsKey: delete.result as? [NSManagedObjectID] ?? []]
    NSManagedObjectContext.mergeChanges(fromRemoteContextSave: changes, into: [context])
  }
}

1. Save the context after deletion.