Removed unneeded 'finish' method from 'cancel' method

Author: wibosco

NetworkingInOperations-Example/Data/Abstract/ConcurrentOperation.swift

@@ -9,14 +9,14 @@
 import Foundation
 import UIKit
 
-enum DataRequestResult<T> {
+enum Result<T> {
     case success(T)
     case failure(Error)
 }
 
 class ConcurrentOperation<T>: Operation {
 
-    typealias OperationCompletionHandler = (_ result: DataRequestResult<T>) -> Void
+    typealias OperationCompletionHandler = (_ result: Result<T>) -> Void
 
     var completionHandler: (OperationCompletionHandler)?
 
@@ -51,12 +51,6 @@ class ConcurrentOperation<T>: Operation {
         return state == .finished
     }
 
-    // MARK: - Asynchronous
-    
-    override var isAsynchronous: Bool {
-        return true
-    }
-    
     // MARK: - Start
 
     override func start() {
@@ -80,7 +74,7 @@ class ConcurrentOperation<T>: Operation {
         }
     }
 
-    func complete(result: DataRequestResult<T>) {
+    func complete(result: Result<T>) {
         finish()
 
         if !isCancelled {

NetworkingInOperations-Example/Data/Managers/Questions/Operations/QuestionsRetrievalOperation.swift

@@ -60,8 +60,7 @@ class QuestionsRetrievalOperation: ConcurrentOperation<QuestionPage> {
     // MARK: - Cancel
 
     override func cancel() {
-        super.cancel()
         task?.cancel()
-        finish()
+        super.cancel()
     }
 }

NetworkingInOperations-Example/Data/Managers/Questions/QuestionsDataManager.swift

@@ -20,7 +20,7 @@ class QuestionsDataManager {
 
     // MARK: - Retrieval
 
-    func retrievalQuestions(pageIndex: Int, completionHandler: @escaping (_ result: DataRequestResult<QuestionPage>) -> Void) {
+    func retrievalQuestions(pageIndex: Int, completionHandler: @escaping (_ result: Result<QuestionPage>) -> Void) {
         let operation = QuestionsRetrievalOperation(pageIndex: pageIndex)
         operation.completionHandler = completionHandler
         queueManager.enqueue(operation)

NetworkingInOperations-Example/Data/Managers/User/Operations/AvatarRetrievalOperation.swift

@@ -55,8 +55,7 @@ class AvatarRetrievalOperation: ConcurrentOperation<(User, UIImage)>  {
     // MARK: - Cancel
 
     override func cancel() {
-        super.cancel()
         task?.cancel()
-        finish()
+        super.cancel()
     }
 }

NetworkingInOperations-Example/Data/Managers/User/UserDataManager.swift

@@ -21,7 +21,7 @@ class UserDataManager {
 
     // MARK: - Avatar
 
-    func retrieveAvatar(forUser user: User, completionHandler: @escaping (_ result: DataRequestResult<(User, UIImage)>) -> Void) {
+    func retrieveAvatar(forUser user: User, completionHandler: @escaping (_ result: Result<(User, UIImage)>) -> Void) {
         let operation = AvatarRetrievalOperation(user: user)
         operation.completionHandler = completionHandler
         queueManager.enqueue(operation)