deleteMany Ignores _skipOffset in RealmResults

[AlexeyKatsuro]

What happened?

The deleteMany method in Realm Dart does not respect the _skipOffset when called on a RealmResults object that was modified using .skip(). As a result, it deletes all elements instead of only those that should be included after skipping.

Root Cause

• The skip() method creates a new RealmResults with an internal _skipOffset.
• The deleteMany implementation calls:

  if (items is RealmResults<T>) {
    _ensureManagedByThis(items, 'delete objects from Realm');
    items.handle.deleteAll();
  }

  • items.handle.deleteAll(); does not account for _skipOffset, leading to all items being deleted.

Expected Behavior

deleteMany(realm.all<Item>().skip(n)) should delete only the remaining items after skipping, not the entire collection.

Repro steps

1. Create an in-memory Realm instance.
2. Add two Item objects.
3. Call realm.all<Item>().skip(1), which returns a RealmResults with an internal _skipOffset.
4. Pass the result to deleteMany.
5. Expectation: The second item should be deleted, as skip(1) skips the first item and results in the second item being the only one left.
6. Actual behavior: deleteMany removes all items.

Version

Flutter 3.29.0 • Dart 3.7.0

What Atlas Services are you using?

Local Database only

What type of application is this?

Dart standalone application

Client OS and version

MacOS

Code snippets

@RealmModel()
class _Item {
  @PrimaryKey()
  late int id;
}

void main() {
  test('deleteMany should respect skip offset', () {
    final realm = Realm(Configuration.inMemory([Item.schema]));
    realm.write(() {
      realm.add(Item(0));
      realm.add(Item(1));
    });

    realm.write(() {
      realm.deleteMany(realm.all<Item>().skip(1));
    });

    expect(realm.all<Item>().length, 1); // Fails: All items are deleted
    realm.close();
  });
}