iOS Unit Testing - View Controller challenge

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1. Unit Testing UIViewController challenge
2. UIViewController Model View Controller! update notify actions update
3. UIViewController Model View Controller! update notify actions update
4. UIViewController Model View Controller! update notify actions update <Protocol> <Protocol> Controller Controller View present present update TableView Facade MapView delegate delegate update Notification! Center Blocks IBOutlets IBActions Notifications API Database Notifications
5. Mocks
6. is a fake object in the system that verifies the system under test interacted as expected with the fake object. Mock Object
7. It is common in unit tests to mock or stub collaborators of the system under test so that the test is independent of the implementation of the collaborators. Mock Object Behavior Verification SUT Setup Exercise Verify Tear Down Behavior ! (Indirect! Outputs) DOC
8. It is common in unit tests to mock or stub collaborators of the system under test so that the test is independent of the implementation of the collaborators. Mock Object Behavior Verification SUT Setup Exercise Verify Tear Down Behavior ! (Indirect! Outputs) Fake
9. It is common in unit tests to mock or stub collaborators of the system under test so that the test is independent of the implementation of the collaborators. Mock Object SUT Behavior Verification Setup Exercise Verify Tear Down Behavior ! (Indirect! Outputs) Fake Verify
10. Test Mocks SUT communicates with the mock object, and all communication is recorded in the mock. The test uses the mock to verify that the test passes. SUT Mock Communicate Assert
11. Test Stubs Returns specified result for a message, stubs can’t fail the test. SUT Stub Communicate Assert
12. UIViewController
13. IBOutlets & IBActions! viewDidLoad! UINavigationController! Class Methods! dealloc How to Test Unit Testing What Is Testing For?
14. IBOutlets & IBActions
15. IBOutlets & IBActions Outlet is connected
16. - (void)setUp { [super setUp]; sut = [ConverterViewController new]; } - (void)tearDown { sut = nil; [super tearDown]; } Is Outlet Connected?
17. - (void)setUp { [super setUp]; sut = [ConverterViewController new]; } - (void)tearDown { sut = nil; [super tearDown]; } - (void)testThatTextFieldOutletIsConnected { XCTAssertNotNil(sut.textField, @"outlet should be connected"); } Is Outlet Connected?
18. - (void)setUp { [super setUp]; sut = [ConverterViewController new]; } - (void)tearDown { sut = nil; [super tearDown]; } - (void)testThatTextFieldOutletIsConnected { XCTAssertNotNil(sut.textField, @"outlet should be connected"); } Is Outlet Connected?
19. - (void)setUp { [super setUp]; sut = [ConverterViewController new]; } - (void)tearDown { sut = nil; [super tearDown]; } - (void)testThatTextFieldOutletIsConnected { [sut view]; XCTAssertNotNil(sut.textField, @"outlet should be connected"); } Is Outlet Connected?
20. IBOutlets & IBActions Outlet has a right action.
21. - (void)testButtonActionBinding { [sut view]; NSArray* acts = [sut.button actionsForTarget:sut forControlEvent:UIControlEventTouchUpInside]; XCTAssert([acts containsObject:@"onButton:"], @"should use correct action"); } Is Action Connected?
22. IBOutlets & IBActions The action does the right things.
23. viewDidLoad
24. viewDidLoad Unit testing of a view controller nearly always means writing the view controller methods differently
25. viewDidLoad - should call helper methods! - each of the helper methods should do just one thing (SOLID principles)! - write tests for each of the helper methods! - test viewDidLoad calls helper methods (partial mock)
26. OCMock
27. OCMock Provides •stub objects that return pre-determined values for specific method invocations! •dynamic mocks that can be used to verify interaction patterns! •partial mocks to overwrite selected methods of existing objects
28. ///Partial mock the system under test to stub out internal methods with expected responses + (id)partialMockForObject:(NSObject *)anObject; id sutMock = [OCMockObject partialMockForObject:sut]; OCMock partial mock
29. UINavigationController
30. UINavigationController - test push view controller! - test pop view controller
31. UINavigationController
32. UINavigationController But
33. UINavigationController But @interface UIViewController (UINavigationControllerItem) @property(nonatomic,readonly,retain) UINavigationController* navigationController; @end
34. -(void)testTappingDetailsShouldDisplayDetails { UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:sut]; id mockNav = [OCMockObject partialMockForObject:nav]; [[mockNav expect] pushViewController:[OCMArg any] animated:YES]; [sut onShowDetailsButton:nil]; [mockNav verify]; } UINavigationController
35. Class Methods
36. Class Methods - test call of methods! - use stub for function
37. id classMock = [OCMockObject mockForClass: [NSNotificationCenter class]]; Class Methods
38. id classMock = [OCMockObject mockForClass: [NSNotificationCenter class]]; [[[classMock stub] andReturn:stub] defaultCenter]; Class Methods
39. id classMock = [OCMockObject mockForClass: [NSNotificationCenter class]]; [[[classMock stub] andReturn:stub] defaultCenter]; Class Methods
40. id classMock = [OCMockObject mockForClass: [NSNotificationCenter class]]; [[[classMock stub] andReturn:stub] defaultCenter]; [classMock stopMocking]; Class Methods
41. dealloc
42. dealloc setUp tearDown zombie
43. dealloc ❓hook dealloc method of SUT when setup! ❓record calling of the hook! ❓verify if hook is called after teardown
44. Aspects
45. /// Adds a block of code before/instead/after the current `selector` for a specific instance. - (id<AspectToken>)aspect_hookSelector:(SEL)selector withOptions:(AspectOptions)options usingBlock:(id)block error:(NSError **)error; /// Called after the original implementation (default) AspectPositionAfter, /// Will replace the original implementation. AspectPositionInstead, /// Called before the original implementation. AspectPositionBefore, Aspects
46. dealloc ✅ hook dealloc method of SUT when setup ! ✅ record calling of the hook! ✅ verify if hook is called after teardown Aspects instance var XCTAssert
47. @interface ConverterViewControllerTests : XCTestCase { ConverterViewController* sut; BOOL _sutDeallocated; } @end - (void)setUp { [super setUp]; sut = [ConverterViewController new]; _sutDeallocated = NO; [sut aspect_hookSelector:NSSelectorFromString(@"dealloc") withOptions:AspectPositionBefore usingBlock:^(id<AspectInfo> aspectInfo){ _sutDeallocated = YES; } error:nil]; } - (void)tearDown { sut = nil; XCTAssertTrue(_sutDeallocated, @"SUT is not deallocated"); [super tearDown]; } dealloc
48. @interface } @end - ( [ } - ( [ } dealloc [sut aspect_hookSelector:NSSelectorFromString(@"dealloc") withOptions:AspectPositionBefore usingBlock:^(id<AspectInfo> aspectInfo){ _sutDeallocated = YES; } error:nil];
49. Testing simple things is simple, ! and ! testing complex things is complex. UIViewController
50. Choosing not to test view controllers is the decision not to test most of your code. UIViewController
51. How to Test • IBOutlets & IBActions! • viewDidLoad! • UINavigationController! • Class Methods! • dealloc Demo Code https:/ /github.com/maksumko/ConverterApp" ! maksum.ko contact me:
52. Sources http://www.amazon.com/Test-Driven-iOS-Development-Developers- Library/dp/0321774183 http://www.objc.io/issue-1/testing-view-controllers.html http://www.silverbaytech.com/2013/02/25/ios-testing-part-3-testing-view- controller/ http://iosunittesting.com/unit-testing-view-controllers/ http://blog.carbonfive.com/2010/03/10/testing-view-controllers/