Merge pull request #7 from PureSwift/feature/decoder

Add `ModelDataDecoder`

Author: colemancda

Sources/CoreDataModel/NSAttributeType.swift

@@ -14,7 +14,7 @@ public extension NSAttributeType {
 
     init(attributeType: AttributeType) {
         switch attributeType {
-        case .boolean:
+        case .bool:
             self = .booleanAttributeType
         case .int16:
             self = .integer16AttributeType
@@ -61,7 +61,7 @@ public extension AttributeType {
         case .stringAttributeType:
             self = .string
         case .booleanAttributeType:
-            self = .boolean
+            self = .bool
         case .dateAttributeType:
             self = .date
         case .binaryDataAttributeType:

Sources/CoreModel/AttributeType.swift

@@ -11,7 +11,7 @@ import Foundation
 public enum AttributeType: String, Codable, CaseIterable, Sendable {
 
     /// Boolean number type.
-    case boolean
+    case bool
 
     /// 16 bit Integer number type.
     case int16

Sources/CoreModel/Decodable.swift

@@ -69,18 +69,46 @@ public extension ModelData {
     }
 }
 
-// MARK: - Default Codable Implementation
+// MARK: - AttributeDecodable
 
-extension Entity where Self: Decodable, Self.ID: Decodable {
+public protocol AttributeDecodable {
 
-    // TODO: Default implementation for Decodable
+    init?(attributeValue: AttributeValue)
 }
 
-// MARK: - AttributeDecodable
+extension Optional: AttributeDecodable where Wrapped: AttributeDecodable {
+    
+    public init?(attributeValue: AttributeValue) {
+        switch attributeValue {
+        case .null:
+            self = .none
+        default:
+            guard let value = Wrapped.init(attributeValue: attributeValue) else {
+                return nil
+            }
+            self = .some(value)
+        }
+    }
+}
 
-public protocol AttributeDecodable {
+extension AttributeDecodable where Self: RawRepresentable, RawValue: AttributeDecodable {
 
-    init?(attributeValue: AttributeValue)
+    public init?(attributeValue: AttributeValue) {
+        guard let rawValue = RawValue.init(attributeValue: attributeValue) else {
+            return nil
+        }
+        self.init(rawValue: rawValue)
+    }
+}
+
+extension Bool: AttributeDecodable {
+    
+    public init?(attributeValue: AttributeValue) {
+        guard case let .bool(value) = attributeValue else {
+            return nil
+        }
+        self = value
+    }
 }
 
 extension String: AttributeDecodable {