Fix PersistentContainerStorage

Author: colemancda

Sources/CoreDataModel/NSManagedObjectContext.swift

@@ -71,7 +71,7 @@ public final class ManagedObjectViewContext: ViewContext, ObservableObject {
         assert(context.concurrencyType == .mainQueueConcurrencyType)
     }
 
-    public nonisolated init(persistentContainer: NSPersistentContainer) {
+    public init(persistentContainer: NSPersistentContainer) {
         self.context = persistentContainer.viewContext
     }
 

Sources/CoreDataModel/NSPersistentContainer.swift

@@ -75,20 +75,27 @@ public actor PersistentContainerStorage: ModelStorage, ObservableObject {
             managedObjectModel: managedObjectModel
         )
         self.persistentContainer = persistentContainer
-        self._viewContext = ManagedObjectViewContext(persistentContainer: persistentContainer)
     }
 
     // MARK: Properties
 
     internal let persistentContainer: NSPersistentContainer
 
-    internal let _viewContext: ManagedObjectViewContext
+    internal nonisolated(unsafe) var _viewContext: ManagedObjectViewContext?
 
     @MainActor
     public var viewContext: ManagedObjectViewContext {
         get throws {
+            // lazily load stores
             try loadStores()
-            return _viewContext
+            // lazily load view context
+            if let viewConext = _viewContext {
+                return viewConext
+            } else {
+                let viewContext = ManagedObjectViewContext(persistentContainer: persistentContainer)
+                _viewContext = viewContext
+                return viewContext
+            }
         }
     }