Realm JavaScript v12.9.0

Enhancements

• A mixed value can now hold a Realm.List and Realm.Dictionary with nested collections. Note that Realm.Set is not supported as a mixed value. (#6613)

class CustomObject extends Realm.Object {
  value!: Realm.Types.Mixed;

  static schema: ObjectSchema = {
    name: "CustomObject",
    properties: {
      value: "mixed",
    },
  };
}

const realm = await Realm.open({ schema: [CustomObject] });

// Create an object with a dictionary value as the Mixed
// property, containing primitives and a list.
const realmObject = realm.write(() => {
  return realm.create(CustomObject, {
    value: {
      num: 1,
      string: "hello",
      bool: true,
      list: [
        {
          string: "world",
        },
      ],
    },
  });
});

// Accessing the collection value returns the managed collection.
const dictionary = realmObject.value;
expectDictionary(dictionary);
const list = dictionary.list;
expectList(list);
const leafDictionary = list[0];
expectDictionary(leafDictionary);
console.log(leafDictionary.string); // "world"

// Update the Mixed property to a list.
realm.write(() => {
  realmObject.value = [1, "hello", { newKey: "new value" }];
});

// Useful custom helper functions. (Will be provided in a future release.)
function expectList(value: unknown): asserts value is Realm.List {
  if (!(value instanceof Realm.List)) {
    throw new Error("Expected a 'Realm.List'.");
  }
}
function expectDictionary(value: unknown): asserts value is Realm.Dictionary {
  if (!(value instanceof Realm.Dictionary)) {
    throw new Error("Expected a 'Realm.Dictionary'.");
  }
}

Fixed

• Inserting the same typed link to the same key in a dictionary more than once would incorrectly create multiple backlinks to the object. This did not appear to cause any crashes later, but would have affecting explicit backlink count queries (eg: ...@links.@count) and possibly notifications (realm/realm-core#7676 since v12.7.1).
• Having links in a nested collections would leave the file inconsistent if the top object is removed. (realm/realm-core#7657, since v12.7.0)
• Automatic client reset recovery would crash when recovering AddInteger instructions on a Mixed property if its type was changed to non-integer (realm/realm-core#7683, since v10.18.0).

Compatibility

• React Native >= v0.71.4
• Realm Studio v15.0.0.
• File format: generates Realms with format v24 (reads and upgrades file format v10).

Internal

• Upgraded Realm Core from v14.6.2 to v14.7.0.
• Upgraded @trunk/launcher from v1.3.0 to v1.3.1 to support Apple's versioning scheme for macOS.