Merge pull request #6 from popei69/develop

Update unit tests for mocked data

TemplateProject.xcodeproj/project.pbxproj

@@ -10,14 +10,15 @@
 		14008A9E20193EB800F84447 /* CurrencyDataSource.swift in Sources */ = {isa = PBXBuildFile; fileRef = 14008A9D20193EB800F84447 /* CurrencyDataSource.swift */; };
 		141895B82023B4BC0029E238 /* CurrencyDataSourceTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 141895B72023B4BC0029E238 /* CurrencyDataSourceTests.swift */; };
 		141895BA2023BBF70029E238 /* CurrencyServiceTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 141895B92023BBF70029E238 /* CurrencyServiceTests.swift */; };
-		141895BC2023C82B0029E238 /* sample.json in Resources */ = {isa = PBXBuildFile; fileRef = 141895BB2023C82B0029E238 /* sample.json */; };
 		141895BE2023C8770029E238 /* CurrencyTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 141895BD2023C8770029E238 /* CurrencyTests.swift */; };
 		142350DC2009668500930F1D /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 142350DB2009668500930F1D /* AppDelegate.swift */; };
 		142350DE2009668500930F1D /* CurrencyViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 142350DD2009668500930F1D /* CurrencyViewController.swift */; };
 		142350E12009668500930F1D /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 142350DF2009668500930F1D /* Main.storyboard */; };
 		142350E32009668500930F1D /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 142350E22009668500930F1D /* Assets.xcassets */; };
 		142350E62009668500930F1D /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 142350E42009668500930F1D /* LaunchScreen.storyboard */; };
 		1456E4B5200A7F2200DCF2AF /* DynamicValue.swift in Sources */ = {isa = PBXBuildFile; fileRef = 1456E4B4200A7F2200DCF2AF /* DynamicValue.swift */; };
+		148CF5E6220A8EEA001DE84B /* FileDataService.swift in Sources */ = {isa = PBXBuildFile; fileRef = 148CF5E5220A8EEA001DE84B /* FileDataService.swift */; };
+		148CF5E7220A8F0B001DE84B /* sample.json in Resources */ = {isa = PBXBuildFile; fileRef = 141895BB2023C82B0029E238 /* sample.json */; };
 		14917E0C200A489A00234393 /* Result.swift in Sources */ = {isa = PBXBuildFile; fileRef = 14917E0B200A489A00234393 /* Result.swift */; };
 		14917E0E200A48AB00234393 /* ErrorResult.swift in Sources */ = {isa = PBXBuildFile; fileRef = 14917E0D200A48AB00234393 /* ErrorResult.swift */; };
 		14917E11200A491C00234393 /* RequestFactory.swift in Sources */ = {isa = PBXBuildFile; fileRef = 14917E10200A491C00234393 /* RequestFactory.swift */; };
@@ -59,6 +60,7 @@
 		142350EC2009668500930F1D /* TemplateProjectTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = TemplateProjectTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		142350F22009668500930F1D /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		1456E4B4200A7F2200DCF2AF /* DynamicValue.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DynamicValue.swift; sourceTree = "<group>"; };
+		148CF5E5220A8EEA001DE84B /* FileDataService.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = FileDataService.swift; path = ../../../../../Desktop/FileDataService.swift; sourceTree = "<group>"; };
 		14917E0B200A489A00234393 /* Result.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Result.swift; sourceTree = "<group>"; };
 		14917E0D200A48AB00234393 /* ErrorResult.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ErrorResult.swift; sourceTree = "<group>"; };
 		14917E10200A491C00234393 /* RequestFactory.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RequestFactory.swift; sourceTree = "<group>"; };
@@ -165,6 +167,7 @@
 				14917E0F200A490400234393 /* Network */,
 				14917E0A200A488D00234393 /* Result */,
 				14917E24200A537600234393 /* CurrencyService.swift */,
+				148CF5E5220A8EEA001DE84B /* FileDataService.swift */,
 			);
 			path = Service;
 			sourceTree = "<group>";
@@ -298,6 +301,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				142350E62009668500930F1D /* LaunchScreen.storyboard in Resources */,
+				148CF5E7220A8F0B001DE84B /* sample.json in Resources */,
 				142350E32009668500930F1D /* Assets.xcassets in Resources */,
 				142350E12009668500930F1D /* Main.storyboard in Resources */,
 			);
@@ -307,7 +311,6 @@
 			isa = PBXResourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				141895BC2023C82B0029E238 /* sample.json in Resources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -318,6 +321,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				148CF5E6220A8EEA001DE84B /* FileDataService.swift in Sources */,
 				14917E19200A508700234393 /* CurrencyCell.swift in Sources */,
 				14917E14200A4ECD00234393 /* Currency.swift in Sources */,
 				14917E23200A530800234393 /* ParserHelper.swift in Sources */,

TemplateProject/Model/DynamicValue.swift

@@ -8,9 +8,11 @@
 
 import Foundation
 
-typealias CompletionHandler = (() -> Void)
+
 class DynamicValue<T> {
 
+    typealias CompletionHandler = ((T) -> Void)
+
     var value : T {
         didSet {
             self.notify()
@@ -33,7 +35,7 @@ class DynamicValue<T> {
     }
 
     private func notify() {
-        observers.forEach({ $0.value() })
+        observers.forEach({ $0.value(value) })
     }
 
     deinit {

TemplateProject/Service/FileDataService.swift

@@ -0,0 +1,42 @@
+//
+//  File.swift
+//  TemplateProject
+//
+//  Created by Benoit PASQUIER on 02/02/2019.
+//  Copyright © 2019 Benoit PASQUIER. All rights reserved.
+//
+
+import Foundation
+
+final class FileDataService : CurrencyServiceProtocol {
+
+    func fetchConverter(_ completion: @escaping ((Result<Converter, ErrorResult>) -> Void)) {
+
+        // giving a sample json file
+        guard let data = FileManager.readJson(forResource: "sample") else {
+            completion(Result.failure(ErrorResult.custom(string: "No file or data")))
+            return
+        }
+
+        ParserHelper.parse(data: data, completion: completion)
+    }
+} 
+
+
+extension FileManager {
+
+    static func readJson(forResource fileName: String ) -> Data? {
+
+        let bundle = Bundle(for: FileDataService.self)
+        if let path = bundle.path(forResource: fileName, ofType: "json") {
+            do {
+                let data = try Data(contentsOf: URL(fileURLWithPath: path), options: .mappedIfSafe)
+                return data
+            } catch {
+                // handle error
+            }
+        }
+
+        return nil
+    }
+}

TemplateProject/View/CurrencyViewController.swift

@@ -25,10 +25,18 @@ class CurrencyViewController: UIViewController {
         self.title = "£ Exchange rate"
 
         self.tableView.dataSource = self.dataSource
-        self.dataSource.data.addAndNotify(observer: self) { [weak self] in
+        self.dataSource.data.addAndNotify(observer: self) { [weak self] _ in
             self?.tableView.reloadData()
         }
 
+        // add error handling example
+        self.viewModel.onErrorHandling = { [weak self] error in
+            // display error ?
+            let controller = UIAlertController(title: "An error occured", message: "Oops, something went wrong!", preferredStyle: .alert)
+            controller.addAction(UIAlertAction(title: "Close", style: .cancel, handler: nil))
+            self?.present(controller, animated: true, completion: nil)
+        }
+
         self.viewModel.fetchCurrencies()
     }
 }

TemplateProject/ViewModel/CurrencyViewModel.swift

@@ -13,33 +13,27 @@ struct CurrencyViewModel {
     weak var dataSource : GenericDataSource<CurrencyRate>?
     weak var service: CurrencyServiceProtocol?
 
-    init(service: CurrencyServiceProtocol = CurrencyService.shared, dataSource : GenericDataSource<CurrencyRate>?) {
+    var onErrorHandling : ((ErrorResult?) -> Void)?
+
+    init(service: CurrencyServiceProtocol = FileDataService.shared, dataSource : GenericDataSource<CurrencyRate>?) {
         self.dataSource = dataSource
         self.service = service
     }
 
-    func fetchCurrencies(_ completion: ((Result<Bool, ErrorResult>) -> Void)? = nil) {
+    func fetchCurrencies() {
 
         guard let service = service else {
-            completion?(Result.failure(ErrorResult.custom(string: "Missing service")))
+            onErrorHandling?(ErrorResult.custom(string: "Missing service"))
             return
         }
 
         service.fetchConverter { result in
-
             DispatchQueue.main.async {
                 switch result {
                 case .success(let converter) :
-                    // reload data
                     self.dataSource?.data.value = converter.rates
-                    completion?(Result.success(true))
-
-                    break
                 case .failure(let error) :
-                    print("Parser error \(error)")
-                    completion?(Result.failure(error))
-
-                    break
+                    self.onErrorHandling?(error)
                 }
             }
         }

TemplateProjectTests/CurrencyTests.swift

@@ -71,21 +71,3 @@ class CurrencyTests: XCTestCase {
         }
     }
 }
-
-extension FileManager {
-
-    static func readJson(forResource fileName: String ) -> Data? {
-
-        let bundle = Bundle(for: CurrencyTests.self)
-        if let path = bundle.path(forResource: fileName, ofType: "json") {
-            do {
-                let data = try Data(contentsOf: URL(fileURLWithPath: path), options: .mappedIfSafe)
-                return data
-            } catch {
-                // handle error
-            }
-        }
-
-        return nil
-    }
-}

TemplateProjectTests/CurrencyViewModelTests.swift

@@ -31,50 +31,53 @@ class CurrencyViewModelTests: XCTestCase {
 
     func testFetchWithNoService() {
 
+        let expectation = XCTestExpectation(description: "No service currency")
+
         // giving no service to a view model
         viewModel.service = nil
 
         // expected to not be able to fetch currencies
-        viewModel.fetchCurrencies { result in
-            switch result {
-            case .success(_) :
-                XCTAssert(false, "ViewModel should not be able to fetch without service")
-            default:
-                break
-            }
+        viewModel.onErrorHandling = { error in 
+            expectation.fulfill()
         }
+
+        viewModel.fetchCurrencies()
+        wait(for: [expectation], timeout: 5.0)
     }
 
     func testFetchCurrencies() {
 
+        let expectation = XCTestExpectation(description: "Currency fetch")
+
         // giving a service mocking currencies
         service.converter = Converter(base: "GBP", date: "01-01-2018", rates: [])
 
-        // expected completion to succeed
-        viewModel.fetchCurrencies { result in
-            switch result {
-            case .failure(_) :
-                XCTAssert(false, "ViewModel should not be able to fetch without service")
-            default:
-                break
-            }
+        viewModel.onErrorHandling = { _ in
+            XCTAssert(false, "ViewModel should not be able to fetch without service")
+        }
+
+        dataSource.data.addObserver(self) { _ in
+            expectation.fulfill()
         }
+
+        viewModel.fetchCurrencies()
+        wait(for: [expectation], timeout: 5.0)
     }
 
     func testFetchNoCurrencies() {
 
+        let expectation = XCTestExpectation(description: "No currency")
+
         // giving a service mocking error during fetching currencies
         service.converter = nil
 
         // expected completion to fail
-        viewModel.fetchCurrencies { result in
-            switch result {
-            case .success(_) :
-                XCTAssert(false, "ViewModel should not be able to fetch ")
-            default:
-                break
-            }
+        viewModel.onErrorHandling = { error in 
+            expectation.fulfill()
         }
+
+        viewModel.fetchCurrencies()
+        wait(for: [expectation], timeout: 5.0)
     }
 }