SwiftData ModelContext Pollution with Multiple ModelContainers and Schemas

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I have two different VersionedSchema accessed via two different and distinct in-memory ModelContainers. However, both schemas have a model named Item.

LocalSchema.Item and RemoteSchema.Item have slightly different properties.

If I create and save RemoteSchema.Item in one context then I cannot create and save LocalSchema.Item in a different context due to missing origin property.

enum LocalSchema: VersionedSchema {
static var versionIdentifier: Schema.Version = .init(1, 0, 0)
    static var models: [any PersistentModel.Type] = [
        Item.self
    ]
@Model
    class Item {
        @Attribute(.unique)
        var title: String
        var created: Date
        var modified: Date
        
        init(title: String, created: Date, modified: Date) {
            self.title = title
            self.created = created
            self.modified = modified
        }
    }  
}

enum RemoteSchema: VersionedSchema {
    static var versionIdentifier: Schema.Version = .init(1, 0, 0)
    static var models: [any PersistentModel.Type] = [
        Item.self
    ]
    
    @Model
    class Item {
        var title: String
        var created: Date
        var modified: Date
        var origin: String
        
        init(title: String, created: Date, modified: Date, origin: String) {
            self.title = title
            self.created = created
            self.modified = modified
            self.origin = origin
        }
    }
}

In the above example, saving RemoteSchema.Item will cause LocalSchema.Item to fail.

The error message I see is

*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<NSManagedObject 0xa120f3750> setValue:forUndefinedKey:]: the entity Item is not key value coding-compliant for the key "origin".'

Test Code

@Test func createLocalItemWithManualSave() async throws {
    let context = ModelContext(try localStore())
    let item = LocalSchema.Item(title: "local", created: .now, modified: .now)
    context.insert(item)
    try context.save()
}

@Test func createRemoteItemWithManualSave() async throws {
    let context = ModelContext(try remoteStore())
    let item = RemoteSchema.Item(title: "remote", created: .now, modified: .now, origin: "from space")
    context.insert(item)
    try context.save()
}

func localStore() throws -> ModelContainer {
    let schema = Schema(versionedSchema: LocalSchema.self)
    let config = ModelConfiguration("local", schema: schema, isStoredInMemoryOnly: true, allowsSave: true, cloudKitDatabase: .none)
    return try ModelContainer(for: schema, configurations: config)
}

func remoteStore() throws -> ModelContainer {
    let schema = Schema(versionedSchema: RemoteSchema.self)
    let config = ModelConfiguration("remote", schema: schema, isStoredInMemoryOnly: true, allowsSave: true, cloudKitDatabase: .none)
    return try ModelContainer(for: schema, configurations: config)
}

I have created FB22310365

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