[sut showAlert]; // Whatever triggers the alert

XCTAssertEqual(alertVerifier.presentedCount, 1, @"presented count"); XCTAssertEqualObjects(alertVerifier.title, @"Hello!", @"title"); XCTAssertEqualObjects(alertVerifier.message, @"How are you?", @"message"); XCTAssertEqual(alertVerifier.animated, YES, @"animated"); XCTAssertEqual(alertVerifier.preferredStyle, UIAlertController.Style.alert, @"preferred style"); XCTAssertIdentical(alertVerifier.presentingViewController, sut, @"presenting view controller"); XCTAssertEqual(alertVerifier.actions.count, 2, @"actions count); XCTAssertEqualObjects(alertVerifier.actions[0].title, @"OK", @"first action"); XCTAssertEqual(alertVerifier.actions[0].style, UIAlertActionStyleDefault, @"first action"); XCTAssertEqualObjects(alertVerifier.actions[1].title, @"Cancel", @"second action"); XCTAssertEqual(alertVerifier.actions[1].style, UIAlertActionStyleCancel, @"second action"); }

### How can I invoke the closure associated with a UIAlertAction?

Go through the steps above to present your alert or action sheet. Then call
executeAction (forButton:) on your AlertVerifier with the button title. For example:

// Now assert what you want }

• (void)test_tappingOK_doesThing

NSError *error = nil; [alertVerifier executeActionForButton:@"OK" andReturnError:&error];

XCTAssertNil(error); // Now add your own assertions }

Because this method can throw an exception, declare the Swift test method as throws and call
the method with try. For Objective-C, pass in an NSError and check that it's not nil.

How do I test a presented view controller?
Instantiate a PresentationVerifier before the Act phase of the test.

Invoke the code to create and present your view controller.

Information about the presentation is then available through the
PresentationVerifier.
For example, here's a test verifying:
- That one view controller was presented, with animation.
 - That the presenting view controller was the System Under Test.
 - That the type of the presented view controller is correct.
 - That the presented view controller has a particular property.
 
sut is the System Under Test in the test fixture. The Swift version uses a handy verify method.

sut.showVC() // Whatever presents the view controller

let nextVC: MyViewController? = presentationVerifier.verify(animated: true, presentingViewController: sut) XCTAssertEqual(nextVC?.specialSetting, "Hello!") }

• (void) test_presentedView_hasSpecialSettingHello

[sut showVC]; // Whatever presents the view controller

XCTAssertEqual(presentationVerifier.presentedCount, 1, @"presented count"); XCTAssertTrue(presentationVerifier.animated, @"animated"); XCTAssertIdentical(presentationVerifier.presentingViewController, sut, @"presenting view controller"); if (![presentationVerifier.presentedViewController isKindOfClass:[MyViewController class]]) { XCTFail(@"Expected MyViewController, but was %@", presentationVerifier.presentedViewController); return; } MyViewController *nextVC = presentationVerifier.presentedViewController; XCTAssertEqualObjects(nextVC.specialSetting, @"Hello!"); }

### How do I test a segue?

It depends. First, follow the steps above for testing a presented view controller. Trigger the
segue from test code. For example, we can trigger a segue attached to a button by calling
sendActions(for: .touchUpInside) on the button.

Segue Type: Present Modally
That's all you need to do. _But you need to be aware of a memory issue:_
Neither the presenting view controller nor the presented view controller will be deallocated
during test execution. This can cause problems during test runs if either affects global state,
such as listening to the NotificationCenter. You may need to add special methods outside of
deinit that allow tests to clean them up.

Segue Type: Show
A "Show" segue (which does push navigation) takes a little more work.
First, install the presenting view controller as the root view controller of a UIWindow. Make
this window visible.

To clean up memory at the end, add this to the beginning of the tearDown() method of the test
suite to pump the run loop:

This ensures that the window is deallocated at the end of the test case. That way, both the view
controllers will also cease to exist.

How do I test dismissing a modal?
Instantiate a DismissalVerifier before the Act phase of the test.

Invoke the code to dismiss your modal.

Information about the dismissal is then available through the
DismissalVerifier.
For example, here's a test verifying that a particular view controller was dismissed, with animation.
 
sut is the System Under Test in the test fixture. The Swift version uses a handy verify method.

sut.dismissVC() // Whatever dismisses the view controller

dismissalVerifier.verify(animated: true, dismissedViewController: sut) }

• (void) test_dismissingView

[sut dismissVC]; // Whatever dismisses the view controller

XCTAssertEqual(dismissalVerifier.dismissedCount, 1, @"dismissed count"); XCTAssertTrue(dismissalVerifier.animated, @"animated"); XCTAssertIdentical(dismissalVerifier.dismissedViewController, sut, @"dismissed view controller"); }

### How can I invoke the closure passed to present or dismiss?

The production code completion handler is captured in the verifier's capturedCompletion property.

How can I test something that's presented or dismissed in a Task or using DispatchQueue.main?
Create an expectation in your test case. Fulfill it in the verifier's testCompletion closure.
Add a short waitForExpectations at the start of the Assert phase.

### Can I see some examples?

There are sample apps in both Swift and Objective-C. Run them on both phone & pad to see what
they do, then read the
ViewControllerAlertTests
and
ViewControllerPresentationTests.
For Swift Testing, read
ViewControllerAlertSwiftTests
and
ViewControllerPresentationSwiftTests.
How Do I Add ViewControllerPresentationSpy to My Project?
Swift Package Manager
Include a ViewControllerPresentationSpy package in your Package.swift manifest's array of dependencies:

### CocoaPods

Add the following to your Podfile, changing "MyTests" to the name of your test target:

### Prebuilt Framework

A prebuilt binary is available on GitHub.
The binary is packaged as ViewControllerPresentationSpy.xcframework, containing these architectures:
Mac Catalyst
iOS device
iOS simulator
tvOS device
tvOS simulator
Drag the XCFramework into your project.

Build Your Own
If you want to build ViewControllerPresentationSpy yourself, clone the repo, then