iOS Unit Testing - Special Cases

iOS Practice Leaders Community Meet-up in Dnipropetrovsk

Transcript

1. Unit Testing Special Cases
2. How to Test
3. UIViewControllers! Block-based code! CoreData How to Test Unit Testing What Is Testing For?
4. UIViewController
5. IBOutlets & IBActions! viewDidLoad! dealloc! UINavigationController UIViewController
6. IBOutlets & IBActions Outlet is connected
7. - (void)setUp { [super setUp]; sut = [ConverterViewController new]; } - (void)tearDown { sut = nil; [super tearDown]; } Is Outlet Connected?
8. - (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?
9. - (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?
10. - (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?
11. IBOutlets & IBActions Outlet has a right action.
12. - (void)testButtonActionBinding { [sut view]; NSArray* acts = [sut.button actionsForTarget:sut forControlEvent:UIControlEventTouchUpInside]; XCTAssert([acts containsObject:@"onButton:"], @"should use correct action"); } Is Action Connected?
13. IBOutlets & IBActions The action does the right things.
14. viewDidLoad Unit testing of a view controller nearly always means writing the view controller methods differently
15. 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)
16. dealloc setUp tearDown zombie
17. dealloc ❓hook dealloc method of SUT when setup! ❓record calling of the hook! ❓verify if hook is called after teardown
18. Aspects
19. /// 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
20. dealloc ✅ hook dealloc method of SUT when setup ! ✅ record calling of the hook! ✅ verify if hook is called after teardown Aspects instance var XCTAssert
21. @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
22. @interface } @end - ( [ } - ( [ } dealloc [sut aspect_hookSelector:NSSelectorFromString(@"dealloc") withOptions:AspectPositionBefore usingBlock:^(id<AspectInfo> aspectInfo){ _sutDeallocated = YES; } error:nil];
23. UINavigationController - test push view controller! - test pop view controller
24. UINavigationController
25. UINavigationController But
26. UINavigationController But @interface UIViewController (UINavigationControllerItem) @property(nonatomic,readonly,retain) UINavigationController* navigationController; @end
27. -(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
28. Choosing not to test view controllers is the decision not to test most of your code. UIViewController
29. Testing simple things is simple, and testing complex things is complex UIViewController
30. Block-based code Why does test fail?
31. Block-based code typedef void(^CompletionHandler)(NSArray * result); - (void)runAsyncCode:(CompletionHandler)completion { dispatch_async(dispatch_get_main_queue(), ^{ completion(nil); }); }
32. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
33. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
34. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
35. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
36. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
37. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
38. Block-based code What can we do?
39. Block-based code
40. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
41. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
42. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert NSDate *timeout = [NSDate dateWithTimeIntervalSinceNow:0.1]; while([timeout timeIntervalSinceNow] > 0 && hasCalledBack == NO) { [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:timeout]; } XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
43. - (void)testRunAsyncCode { // arrange __block BOOL hasCalledBack = NO; // act [sut runAsyncCode:^(NSArray *result) { hasCalledBack = YES; }]; // assert NSDate *timeout = [NSDate dateWithTimeIntervalSinceNow:0.1]; while([timeout timeIntervalSinceNow] > 0 && hasCalledBack == NO) { [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:timeout]; } XCTAssert(hasCalledBack, @"Test timed out"); } Block-based code
44. Block-based code Also we can use: - (void)verifyWithDelay:(NSTimeInterval)delay { NSTimeInterval step = 0.01; while(delay > 0) { if([expectations count] == 0) break; NSDate* until = [NSDate dateWithTimeIntervalSinceNow:step]; [[NSRunLoop currentRunLoop] runUntilDate:until]; delay -= step; step *= 2; } [self verify]; } OCMock
45. CoreData
46. CoreData As long as you don't put business logic in your models, you don't have to test them.
47. CoreData creates setters & getters in run-time
48. CoreData creates setters & getters in run-time we can’t mock CoreData models
49. CoreData What can we do?
50. CoreData - create protocol that has all model’s properties defined! - conform NSManagedObject to the protocol! - create NSObject model just for testing, conforms to the protocol and @synthesize properties
51. CoreData Protocol Model<Protocol> TestModel<Protocol>
52. CoreData Protocol Model<Protocol> TestModel<Protocol>
53. CoreData Have a better solution?
54. CoreData Create own CoreData stack for each test-case
55. - (void)setUp { [super setUp]; NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"SimpleInvoice" withExtension:@“momd"]; NSManagedObjectModel *mom = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL]; NSPersistentStoreCoordinator *psc = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:mom]; XCTAssertNotNil([psc addPersistentStoreWithType:NSInMemoryStoreType configuration:nil URL:nil options:nil error:NULL], @"Should be able to add in-memory store”); _moc = [[NSManagedObjectContext alloc] init]; _moc.persistentStoreCoordinator = psc; } CoreData
56. - (void { [ initWithContentsOfURL initWithManagedObjectModel } CoreData - (void)setUp { XCTAssertNotNil([psc addPersistentStoreWithType:NSInMemoryStoreType configuration:nil URL:nil options:nil error:NULL], @"Should be able to add in-memory store”); }
57. CoreData Advantages?
58. CoreData Advantages? - no additional classes! - no dependence on external state! - close approximation to the application environment! - we are able to create base test class with a stack and subclass it where we need
59. CoreData Advantages? - no additional classes! - no dependence on external state! - close approximation to the application environment! - we are able to create base test class with a stack and subclass it where we need
60. - (void)testFullNameReturnsСorrectString { Person* ps; ps = [NSEntityDescription insertNewObjectForEntityForName:@"Person" inManagedObjectContext:_moc]; ps.firstName = @"Tom"; ps.lastName = @“Lol"; STAssertTrue([[ps fullName] isEqualToString:@"Lol Tom"], @"should have matched full name"); } CoreData
61. CoreData - test model’s additional business-logic! - test ManagedObjectModel for an entity! - create and use models as a mocks
62. ✅ UIViewControllers! ✅ Block-based code! ✅ CoreData How to Test
63. Video is coming! https:/ /github.com/maksum ! maksum.ko contact me:
64. 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/ http://iosunittesting.com/how-to-unit-test-completion-blocks/ http://iosunittesting.com/unit-testing-core-data/ http://ashfurrow.com/blog/unit-testing-with-core-data-models http://www.sicpers.info/2010/06/template-class-for-unit-testing-core-data-entities/ http://iamleeg.blogspot.com/2010/01/unit-testing-core-data-driven-apps-fit.html