Hi, I am trying my first SwiftData migration, but my custom migration stage never gets called. Since I am not sure if this is a bug with the current beta of if I am "holding it wrong" I was wondering, if anybody got migration working (their MigrationStage.custom called)? Would be great, if you could just let me know, if you got it working or running into the same issue! :-) Thank you! Cheers, Michael

Hi, when inserting an entity with a relationship I get the following runtime error: Illegal attempt to establish a relationship 'group' between objects in different contexts [...]. The model looks like this: @Model class Person { var name: String @Relationship(.nullify, inverse: \Group.members) var group: Group init(name: String) { self.name = name } } @Model class Group { var name: String @Relationship(.cascade) public var members: [Person] init(name: String) { self.name = name } } It can be reproduced using this (contrived) bit of code: let group = Group(name: "Group A") ctx.insert(group) try! ctx.save() let descriptor = FetchDescriptor<Group>() let groups = try ctx.fetch(descriptor) XCTAssertFalse(groups.isEmpty) XCTAssertEqual(groups.count, 1) XCTAssertTrue(groups.first?.name == "Group A") let person = Person(name: "Willy") person.group = group ctx.insert(person) try ctx.save() (See also full test case below). Anybody experiencing similar issues? Bug or feature? Cheers, Michael Full test case: import SwiftData import SwiftUI import XCTest // MARK: - Person - @Model class Person { var name: String @Relationship(.nullify, inverse: \Group.members) var group: Group init(name: String) { self.name = name } } // MARK: - Group - @Model class Group { var name: String @Relationship(.cascade) public var members: [Person] init(name: String) { self.name = name } } // MARK: - SD_PrototypingTests - final class SD_PrototypingTests: XCTestCase { var container: ModelContainer! var ctx: ModelContext! override func setUpWithError() throws { let fullSchema = Schema([Person.self, Group.self,]) let dbCfg = ModelConfiguration(schema: fullSchema) container = try ModelContainer(for: fullSchema, dbCfg) ctx = ModelContext(container) _ = try ctx.delete(model: Group.self) _ = try ctx.delete(model: Person.self) } override func tearDownWithError() throws { guard let dbURL = container.configurations.first?.url else { XCTFail("Could not find db URL") return } do { try FileManager.default.removeItem(at: dbURL) } catch { XCTFail("Could not delete db: \(error)") } } func testRelAssignemnt_FB12363892() throws { let group = Group(name: "Group A") ctx.insert(group) try! ctx.save() let descriptor = FetchDescriptor<Group>() let groups = try ctx.fetch(descriptor) XCTAssertFalse(groups.isEmpty) XCTAssertEqual(groups.count, 1) XCTAssertTrue(groups.first?.name == "Group A") let person = Person(name: "Willy") person.group = group ctx.insert(person) try ctx.save() } }

Hi, using the following ContentView in a SwiftUI app on macOS I would expect that the state of the toggle persists across application launches: struct ContentView: View { @SceneStorage("Toggle") var onOrOff: Bool = false var body: some View { VStack { Toggle("Will it persist?", isOn: $onOrOff) .padding() } } } To my surprise it does not persist. Am I wrong about how @SceneStorage should work? (I am trying this on the lates macOS/Xcode versions) Does @SceneStorage work for anybody on macOS? Thanks for your feedback! Cheers, Michael

Hi, say in my model I have members and each member optionally can have a relationship to a Club. So the relationship in the Member entity would be modelled like so: @Relationship(.nullify, inverse: \Club.members) var club: Club? Now I would like to fetch al Members with no Club relationship. I would assume that this would work with a predicate like this: let noClubPred = #Predicate<Member> { member in member.club == nil } Unfortunately this gives me the following error when compiling: Generic parameter 'RHS' could not be inferred. Has anybody an idea how to phrase this predicate correctly, or is this a beta issue and it should actually work? Thank you! Cheers, Michael

Hi, if I have a @Model class there's always an id: PersistentIdentifier.ID underneath which, according to the current documentation "The value that uniquely identifies the associated model within the containing store.". So I am wondering if it is (good) enough to rely on this attribute to uniquely identify @Model class entities, or if there are edge cases where it does not work (like maybe when using CloudKit)? If anybody saw some information regarding this, please let me know :-) Cheers, Michael

Hi, I am inserting two models where the "unique" attribute is the same. I was under the impression, that this should result in an upsert and not two inserts of the model, but that is not the case. See the test coding below for what I am doing (it is self contained, so if you want to try it out, just copy it into a test target). The last #expect statement fails because of the two inserts. Not sure if this is a bug (Xcode 16 beta 2 on Sonoma running an iOS 18 simulator) or if I am missing something here... // MARK: - UniqueItem - @Model final class UniqueItem { #Unique<UniqueItem>([\.no]) var timestamp = Date() var title: String var changed = false var no: Int init(title: String, no: Int) { self.title = title self.no = no } } // MARK: - InsertTests - @Suite("Insert Tests", .serialized) struct InsertTests { var sharedModelContainer: ModelContainer = { let schema = Schema([ UniqueItem.self, ]) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer(for: schema, configurations: [modelConfiguration]) } catch { fatalError("Could not create ModelContainer: \(error)") } }() @Test("Test unique.") @MainActor func upsertAndModify() async throws { let ctx = sharedModelContainer.mainContext try ctx.delete(model: UniqueItem.self) let item = UniqueItem(title: "Item \(1)", no: 0) ctx.insert(item) let allFD = FetchDescriptor<UniqueItem>() let count = try ctx.fetchCount(allFD) #expect(count == 1) let updatedItem = UniqueItem(title: "Item \(1)", no: 0) updatedItem.changed = true ctx.insert(updatedItem) // we should still have only 1 item because of the unique constraint let allCount = try ctx.fetchCount(allFD) #expect(allCount == 1) } }

Hi, is there any description/documentation about what can not be used as SwiftData attributes? I do not mean things which cause issues at compile time, like having a type which is not Codeable. But rather I am looking for info which things to avoid, if you do not want to run into application crashes in modelContext.save(). Like for example having an enum which as an optional associated value as an attribute type (crashes on save is the associated value is nil). Anybody seen any documentation about that? Or tech notes? Thanks in advance for any hints :-). Cheers, Michael