Add XCTest extensions (#57)

* Added expectations for on request and completion

* Updated the readme

Author: AvdLee

Mocker.xcodeproj/project.pbxproj

@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		501B8FC4247E89C600B885F4 /* XCTest+Mocker.swift in Sources */ = {isa = PBXBuildFile; fileRef = 501B8FC3247E89C600B885F4 /* XCTest+Mocker.swift */; };
 		501E269E1F3DAE370048F39E /* Mocker.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 501E26941F3DAE370048F39E /* Mocker.framework */; };
 		503446171F3DB4660039D5E4 /* Mock.swift in Sources */ = {isa = PBXBuildFile; fileRef = 503446141F3DB4660039D5E4 /* Mock.swift */; };
 		503446181F3DB4660039D5E4 /* Mocker.swift in Sources */ = {isa = PBXBuildFile; fileRef = 503446151F3DB4660039D5E4 /* Mocker.swift */; };
@@ -28,6 +29,8 @@
 /* End PBXContainerItemProxy section */
 
 /* Begin PBXFileReference section */
+		501B8FC3247E89C600B885F4 /* XCTest+Mocker.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "XCTest+Mocker.swift"; sourceTree = "<group>"; };
+		501B8FC5247E8BDE00B885F4 /* README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };
 		501E26941F3DAE370048F39E /* Mocker.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Mocker.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		501E269D1F3DAE370048F39E /* MockerTests.xctest */ = {isa = PBXFileReference; explicitFileType = wrapper.cfbundle; includeInIndex = 0; path = MockerTests.xctest; sourceTree = BUILT_PRODUCTS_DIR; };
 		501F8B2D237594AC008EF77E /* Mocker.podspec */ = {isa = PBXFileReference; lastKnownFileType = text; path = Mocker.podspec; sourceTree = "<group>"; };
@@ -65,6 +68,7 @@
 		501E268A1F3DAE370048F39E = {
 			isa = PBXGroup;
 			children = (
+				501B8FC5247E8BDE00B885F4 /* README.md */,
 				506277CC235F2777000A4316 /* Changelog.md */,
 				501F8B2D237594AC008EF77E /* Mocker.podspec */,
 				501E26951F3DAE370048F39E /* Products */,
@@ -89,6 +93,7 @@
 				503446141F3DB4660039D5E4 /* Mock.swift */,
 				503446151F3DB4660039D5E4 /* Mocker.swift */,
 				503446161F3DB4660039D5E4 /* MockingURLProtocol.swift */,
+				501B8FC3247E89C600B885F4 /* XCTest+Mocker.swift */,
 			);
 			path = Sources;
 			sourceTree = "<group>";
@@ -264,6 +269,7 @@
 			buildActionMask = 2147483647;
 			files = (
 				503446191F3DB4660039D5E4 /* MockingURLProtocol.swift in Sources */,
+				501B8FC4247E89C600B885F4 /* XCTest+Mocker.swift in Sources */,
 				503446181F3DB4660039D5E4 /* Mocker.swift in Sources */,
 				503446171F3DB4660039D5E4 /* Mock.swift in Sources */,
 			);
@@ -419,6 +425,9 @@
 				DYLIB_COMPATIBILITY_VERSION = 1;
 				DYLIB_CURRENT_VERSION = 1;
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
+				FRAMEWORK_SEARCH_PATHS = (
+					"$(PLATFORM_DIR)/Developer/Library/Frameworks\n$(PLATFORM_DIR)/Developer/Library/Frameworks",
+				);
 				INFOPLIST_FILE = "Mocker/Supporting Files/Info.plist";
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
 				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
@@ -439,6 +448,9 @@
 				DYLIB_COMPATIBILITY_VERSION = 1;
 				DYLIB_CURRENT_VERSION = 1;
 				DYLIB_INSTALL_NAME_BASE = "@rpath";
+				FRAMEWORK_SEARCH_PATHS = (
+					"$(PLATFORM_DIR)/Developer/Library/Frameworks\n$(PLATFORM_DIR)/Developer/Library/Frameworks",
+				);
 				INFOPLIST_FILE = "Mocker/Supporting Files/Info.plist";
 				INSTALL_PATH = "$(LOCAL_LIBRARY_DIR)/Frameworks";
 				IPHONEOS_DEPLOYMENT_TARGET = 10.0;

MockerTests/MockerTests.swift

@@ -346,6 +346,32 @@ final class MockerTests: XCTestCase {
         request.httpMethod = Mock.HTTPMethod.put.rawValue
         XCTAssertNotNil(Mocker.mock(for: request))
     }
+
+    /// It should call the on request expectation.
+    func testOnRequestExpectation() {
+        let url = URL(string: "https://www.fakeurl.com")!
+
+        var mock = Mock(url: url, dataType: .json, statusCode: 200, data: [.get: Data()])
+        let expectation = expectationForRequestingMock(&mock)
+        mock.register()
+
+        URLSession.shared.dataTask(with: URLRequest(url: url)).resume()
+
+        wait(for: [expectation], timeout: 2.0)
+    }
+
+    /// It should call the on completion expectation.
+    func testOnCompletionExpectation() {
+        let url = URL(string: "https://www.fakeurl.com")!
+
+        var mock = Mock(url: url, dataType: .json, statusCode: 200, data: [.get: Data()])
+        let expectation = expectationForCompletingMock(&mock)
+        mock.register()
+
+        URLSession.shared.dataTask(with: URLRequest(url: url)).resume()
+
+        wait(for: [expectation], timeout: 2.0)
+    }
 
     /// it should return the error we requested from the mock when we pass in an Error.
     func testMockReturningError() {
@@ -374,6 +400,5 @@ final class MockerTests: XCTestCase {
         }.resume()
 
         waitForExpectations(timeout: 10.0, handler: nil)
-
     }
 }

README.md

@@ -188,22 +188,6 @@ let ignoredURL = URL(string: "www.wetransfer.com")!
 Mocker.ignore(ignoredURL)
 ```
 
-##### Mock callbacks
-You can register on `Mock` callbacks to make testing easier.
-
-```swift
-var mock = Mock(url: request.url!, dataType: .json, statusCode: 200, data: [.post: Data()])
-mock.onRequest = { request, postBodyArguments in
-    XCTAssertEqual(request.url, mock.request.url)
-    XCTAssertEqual(expectedParameters, postBodyArguments as? [String: String])
-    onRequestExpectation.fulfill()
-}
-mock.completion = {
-    endpointIsCalledExpectation.fulfill()
-}
-mock.register()
-```
-
 ##### Mock errors
 
 You can request a `Mock` to return an error, allowing testing of error handling.
@@ -227,6 +211,36 @@ URLSession.shared.dataTask(with: originalURL) { (data, urlresponse, err) in
 }.resume()
 ```
 
+##### Mock callbacks
+You can register on `Mock` callbacks to make testing easier.
+
+```swift
+var mock = Mock(url: request.url!, dataType: .json, statusCode: 200, data: [.post: Data()])
+mock.onRequest = { request, postBodyArguments in
+    XCTAssertEqual(request.url, mock.request.url)
+    XCTAssertEqual(expectedParameters, postBodyArguments as? [String: String])
+    onRequestExpectation.fulfill()
+}
+mock.completion = {
+    endpointIsCalledExpectation.fulfill()
+}
+mock.register()
+```
+
+##### Mock expectations
+Instead of setting the `completion` and `onRequest` you can also make use of expectations:
+
+```swift
+var mock = Mock(url: url, dataType: .json, statusCode: 200, data: [.get: Data()])
+let requestExpectation = expectationForCompletingMock(&mock)
+let completionExpectation = expectationForCompletingMock(&mock)
+mock.register()
+
+URLSession.shared.dataTask(with: URLRequest(url: url)).resume()
+
+wait(for: [requestExpectation, completionExpectation], timeout: 2.0)
+```
+
 ## Communication
 
 - If you **found a bug**, open an issue.

Sources/Mock.swift

@@ -9,6 +9,7 @@
 //  swiftlint:disable force_unwrapping
 
 import Foundation
+import XCTest
 
 /// A Mock which can be used for mocking data requests with the `Mocker` by calling `Mocker.register(...)`.
 public struct Mock: Equatable {
@@ -103,6 +104,12 @@ public struct Mock: Equatable {
 
     /// The callback which will be executed everytime this `Mock` was started. Can be used within unit tests for validating that a request has been started. The callback must be set before calling `register`.
     public var onRequest: OnRequest?
+
+    /// Can only be set internally as it's used by the `expectationForRequestingMock(_:)` method.
+    var onRequestExpectation: XCTestExpectation?
+
+    /// Can only be set internally as it's used by the `expectationForCompletingMock(_:)` method.
+    var onCompletedExpectation: XCTestExpectation?
 
     private init(url: URL? = nil, ignoreQuery: Bool = false, dataType: DataType, statusCode: Int, data: [HTTPMethod: Data], requestError: Error? = nil, additionalHeaders: [String: String] = [:], fileExtensions: [String]? = nil) {
         self.urlToMock = url

Sources/MockingURLProtocol.swift

@@ -46,6 +46,7 @@ public final class MockingURLProtocol: URLProtocol {
         if let onRequest = mock.onRequest {
             onRequest(request, request.postBodyArguments)
         }
+        mock.onRequestExpectation?.fulfill()
 
         guard let delay = mock.delay else {
             finishRequest(for: mock, data: data, response: response)
@@ -72,6 +73,7 @@ public final class MockingURLProtocol: URLProtocol {
         }
 
         mock.completion?()
+        mock.onCompletedExpectation?.fulfill()
     }
 
     /// Implementation does nothing, but is needed for a valid inheritance of URLProtocol.

Sources/XCTest+Mocker.swift

@@ -0,0 +1,24 @@
+//
+//  XCTest+Mocker.swift
+//  Mocker
+//
+//  Created by Antoine van der Lee on 27/05/2020.
+//  Copyright © 2020 WeTransfer. All rights reserved.
+//
+
+import Foundation
+import XCTest
+
+public extension XCTestCase {
+    func expectationForRequestingMock(_ mock: inout Mock) -> XCTestExpectation {
+        let mockExpectation = expectation(description: "\(mock) should be requested")
+        mock.onRequestExpectation = mockExpectation
+        return mockExpectation
+    }
+
+    func expectationForCompletingMock(_ mock: inout Mock) -> XCTestExpectation {
+        let mockExpectation = expectation(description: "\(mock) should be finishing")
+        mock.onCompletedExpectation = mockExpectation
+        return mockExpectation
+    }
+}