使用XCTest测试PresentedViewController

Question

I have method which I would like to test:

- (void)sendMailToContact:(Contact *)conact
{
    self.contact = conact;

    if ([self isSendingAvaiable]) {

        MFMailComposeViewController *mailViewController = [[MFMailComposeViewController alloc] init];
        mailViewController.mailComposeDelegate = self;
        [mailViewController setToRecipients:@[self.contact.email]];

        [self.parentViewController presentViewController:mailViewController animated:YES completion:nil];
    }
}

The test...

- (void)testSendMailToContact_itShouldShowMFMailComposeViewController
{
    UIViewController *mockViewController = [[UIViewController alloc] init];
    [mockViewController viewDidLoad];

    MailComposer *mockMailComposer = [MailComposer sharedComposerWithController:mockViewController];

    [mockMailComposer sendMailToContact:[self mockContact]];

    XCTAssertTrue([mockViewController.presentedViewController isKindOfClass:[MFMailComposeViewController class]], @"");
}

But It not work correctly. I should have MFMailComposeViewController as presentedViewController but I have null. I don't know what to do. Please help!

Answer 1

The problem is that mockViewController is not in UIWindow hierarchy. Try:

[UIApplication sharedApplication].keyWindow.rootViewController = mockViewController;

Then you can also get rid of viewDidLoad call.

Answer 2

Here's the Swift 4 solution:

let vc = UIViewController()
UIApplication.shared.keyWindow?.rootViewController = vc

In your test…

XCTAssert(vc.presentedViewController is MyCustomViewController)

Answer 3

Your test case contains some issues. You are presenting the MFMailComposeViewController from MailComposer . So you should call the presentedViewController on mockMailComposer not on mockViewController .

Change that to:

- (void)testSendMailToContact_itShouldShowMFMailComposeViewController
{
    MailComposer *mockMailComposer = [MailComposer sharedComposerWithController:mockViewController];

    [mockMailComposer sendMailToContact:[self mockContact]];

    XCTAssertTrue([mockMailComposer.presentedViewController isKindOfClass:[MFMailComposeViewController class]], @"");
}

Answer 4

It looks as though you need 2 parts to your test (or 2 separate tests). The first part should ensure that isSendingAvaiable is NO and test that mockViewController.presentedViewController is nil . The second part should ensure that isSendingAvaiable is YES and test that mockViewController.presentedViewController is of the appropriate class.

When a test fails it is important to determine whether the fault lies with the code being testing or with the test itself.

Perhaps the issue is that isSendingAvaiable is NO .

Answer 5

Add your root ViewController instance to a UIWindow before testing, no need to use UIApplication.shared.keyWindow?.rootViewController as mentioned above.

let window = UIWindow()
window.rootViewController = yourRootViewController
window.makeKeyAndVisible()


XCTAssert(yourRootViewController.presentedViewController is YourModalViewController)