WIP: allow migrations for CoreStoreObjects

Sources/Internal/EntityIdentifier.swift

@@ -0,0 +1,106 @@
+//
+//  EntityIdentifier.swift
+//  CoreStore
+//
+//  Copyright © 2017 John Rommel Estropia
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in all
+//  copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//  SOFTWARE.
+//
+
+import CoreData
+import Foundation
+
+
+// MARK: - EntityIdentifier
+
+internal struct EntityIdentifier: Hashable {
+    
+    // MARK: - Category
+    
+    internal enum Category: Int {
+        
+        case coreData
+        case coreStore
+    }
+    
+    
+    // MARK: -
+    
+    internal let category: Category
+    internal let interfacedClassName: String
+    
+    internal init(_ type: NSManagedObject.Type) {
+        
+        self.category = .coreData
+        self.interfacedClassName = String(reflecting: type)
+    }
+    
+    internal init(_ type: CoreStoreObject.Type) {
+        
+        self.category = .coreStore
+        self.interfacedClassName = String(reflecting: type)
+    }
+    
+    internal init(_ type: DynamicObject.Type) {
+        
+        switch type {
+            
+        case let type as NSManagedObject.Type:
+            self.init(type)
+            
+        case let type as CoreStoreObject.Type:
+            self.init(type)
+            
+        default:
+            CoreStore.abort("\(cs_typeName(DynamicObject.self)) is not meant to be implemented by external types.")
+        }
+    }
+    
+    internal init(_ entityDescription: NSEntityDescription) {
+        
+        if let anyEntity = entityDescription.anyEntity {
+            
+            self.category = .coreStore
+            self.interfacedClassName = NSStringFromClass(anyEntity.type)
+        }
+        else {
+            
+            self.category = .coreData
+            self.interfacedClassName = entityDescription.managedObjectClassName!
+        }
+    }
+    
+    
+    // MARK: Equatable
+    
+    static func == (lhs: EntityIdentifier, rhs: EntityIdentifier) -> Bool {
+        
+        return lhs.category == rhs.category
+            && lhs.interfacedClassName == rhs.interfacedClassName
+    }
+    
+    
+    // MARK: Hashable
+    
+    var hashValue: Int {
+        
+        return self.category.hashValue
+            ^ self.interfacedClassName.hashValue
+    }
+}