cleanup NSError conversion for ObjC

Author: jaeopt

OptimizelySDK/Optimizely/OptimizelyClient+ObjC.swift

@@ -70,7 +70,7 @@ extension OptimizelyClient {
         start { result in
             switch result {
             case .failure(let error):
-                completion?(nil, self.convertErrorForObjc(error))
+                completion?(nil, error as NSError)
             case .success(let data):
                 completion?(data, nil)
             }
@@ -347,25 +347,6 @@ extension OptimizelyClient {
         }
     }
 
-    /// Conver Swift Error for Objective-C interfaces
-    ///
-    /// - Parameter error: Swift Error
-    /// - Returns: Objective-C NSError converted
-    func convertErrorForObjc(_ error: Error) -> NSError {
-        var errorInObjc: NSError
-        
-        // TODO: [Jae] add more details for error types
-        
-        switch error {
-        default:
-            errorInObjc = NSError(domain: "com.optimizely.OptimizelySwiftSDK",
-                                  code: 1000,
-                                  userInfo: [NSLocalizedDescriptionKey: error.localizedDescription])
-        }
-        
-        return errorInObjc
-    }
-    
     @available(swift, obsoleted: 1.0)
     @objc(notificationCenter)
     /// NotificationCenter for Objective-C interface support

OptimizelySDK/Optimizely/OptimizelyError.swift

@@ -75,6 +75,8 @@ public enum OptimizelyError: Error {
     case eventDispatchFailed(_ reason: String)
 }
 
+// MARK: - CustomStringConvertible
+
 extension OptimizelyError: CustomStringConvertible {
     public var description: String {
         return "[Optimizely][Error] " + self.reason
@@ -135,3 +137,12 @@ extension OptimizelyError: CustomStringConvertible {
         return message
     }
 }
+
+// MARK: - LocalizedError (ObjC NSError)
+
+extension OptimizelyError: LocalizedError {
+    public var errorDescription: String? {
+        return self.reason
+    }
+}
+