Realm v10.30.0 Release Notes

Release Date: 2022-09-20 // 11 days ago
  • ๐Ÿ›  Fixed

    • Incoming links from RealmAny properties were not handled correctly when migrating an object type from top-level to embedded. RealmAny properties currently cannot link to embedded objects. (Core #5796, since 10.8.0).
    • โœ… Realm.refresh() sometimes did not actually advance to the latest version. It attempted to be semi-non-blocking in a very confusing way which resulted in it sometimes advancing to a newer version that is not the latest version, and sometimes blocking until notifiers are ready so that it could advance to the latest version. This behavior was undocumented and didn't work correctly, so it now always blocks if needed to advance to the latest version. (#7625, since v0.98.0).
    • ๐Ÿ›  Fix the most common cause of thread priority inversions when performing writes on the main thread. If beginning the write transaction has to wait for the background notification calculations to complete, that wait is now done in a QoS-aware way. (#7902)
    • ๐Ÿ”€ Subscribing to link properties in a flexible sync Realm did not work due to a mismatch between what the client sent and what the server needed. (Core #5409)
    • ๐Ÿ”€ Attempting to use AsymmetricObject with partition-based sync now reports a sensible error much earlier in the process. Asymmetric sync requires using flexible sync. (Core #5691, since 10.29.0).
    • Case-insensitive but diacritic-sensitive queries would crash on 4-byte UTF-8 characters (Core #5825, since v2.2.0)
    • Accented characters are now handled by case-insensitive but diacritic-sensitive queries. (Core #5825, since v2.2.0)

    ๐Ÿ’ฅ Breaking Changes

    • -[RLMASLoginDelegate authenticationDidCompleteWithError:] has been renamed to -[RLMASLoginDelegate authenticationDidFailWithError:] to comply with new app store requirements. This only effects the obj-c API. (#7945)


    • Realm Studio: 11.0.0 or later.
    • ๐Ÿš€ APIs are backwards compatible with all previous releases in the 10.x.y series.
    • ๐Ÿš€ Carthage release for Swift is built with Xcode 13.4.1.
    • CocoaPods: 1.10 or later.
    • Xcode: 13.1 - 14.


    • โฌ†๏ธ Upgraded realm-core from 12.6.0 to 12.7.0

Previous changes from v10.29.0

  • โœจ Enhancements

    • โž• Add support for asymmetric sync. When a class inherits from AsymmetricObject, objects created are synced unidirectionally to the server and cannot be queried or read locally.
        class PersonObject: AsymmetricObject {
           @Persisted(primaryKey: true) var _id: ObjectId
           @Persisted var name: String
           @Persisted var age: Int
        try realm.write {
           // This will create the object on the server but not locally.
           realm.create(PersonObject.self, value: ["_id": ObjectId.generate(),
                                                   "name": "Dylan",
                                                   "age": 20])
    • โž• Add ability to section a collection which conforms to RealmCollection, RLMCollection. Collections can be sectioned by a unique key retrieved from a keyPath or a callback and will return an instance of SectionedResults/RLMSectionedResults. Each section in the collection will be an instance of ResultsSection/RLMSection which gives access to the elements corresponding to the section key. SectionedResults/RLMSectionedResults and ResultsSection/RLMSection have the ability to be observed. swift class DemoObject: Object { @Persisted var title: String @Persisted var date: Date var firstLetter: String { return ?? "" } } var sectionedResults: SectionedResults<String, DemoObject> // ... sectionedResults = realm.objects(DemoObject.self) .sectioned(by: \.firstLetter, ascending: true)
    • โž• Add @ObservedSectionedResults for SwiftUI support. This property wrapper type retrieves sectioned results from a Realm using a keyPath or callback to determine the section key.

      struct DemoView: View {
                                  sectionKeyPath: \.firstLetter) var demoObjects
        var body: some View {
            VStack {
                List {
                    ForEach(demoObjects) { section in
                        Section(header: Text(section.key)) {
                            ForEach(section) { object in
                                MyRowView(object: object)
    • โž• Add automatic handing for changing top-level objects to embedded objects in migrations. Any objects of the now-embedded type which have zero incoming links are deleted, and objects with multiple incoming links are duplicated. This happens after the migration callback function completes, so there is no functional change if you already have migration logic which correctly handles this. (Core #5737).

    • ๐Ÿ‘Œ Improve performance when a new Realm file connects to the server for the first time, especially when significant amounts of data has been written while offline. (Core #5772)

    • ๐Ÿ”€ Shift more of the work done on the sync worker thread out of the write transaction used to apply server changes, reducing how long it blocks other threads from writing. (Core #5772)

    • ๐Ÿ‘Œ Improve the performance of the sync changeset parser, which speeds up applying changesets from the server. (Core #5772)

    ๐Ÿ›  Fixed

    • ๐Ÿ›  Fix all of the UBSan failures hit by our tests. It is unclear if any of these manifested as visible bugs. (Core #5665)
    • Upload completion callbacks were sometimes called before the final step of interally marking the upload as complete, which could result in calling Realm.writeCopy() from the completion callback failing due to there being unuploaded changes. (Core #4865).
    • ๐Ÿ‘ป Writing to a Realm stored on an exFAT drive threw the exception "fcntl() with F_BARRIERFSYNC failed: Inappropriate ioctl for device" when a write transaction needed to expand the file. (Core #5789, since 10.27.0)
    • ๐Ÿ”€ Syncing a Decimal128 with big significand could result in a crash. (Core #5728)


    • Realm Studio: 11.0.0 or later.
    • ๐Ÿš€ APIs are backwards compatible with all previous releases in the 10.x.y series.
    • ๐Ÿš€ Carthage release for Swift is built with Xcode 13.4.1.
    • CocoaPods: 1.10 or later.
    • Xcode: 13.1-14 RC.


    • โฌ†๏ธ Upgraded realm-core from 12.5.1 to 12.6.0