Sample iOS Unit Tests: Working with NavigationItems

Sample iOS Unit Tests: Working with NavigationItems

// example unit tests for UIBarButtonItem target - action pattern

import XCTest
@testable import to

class ViewControllerTest: XCTestCase {

    var systemUnderTest: ViewController!
    
    override func setUp() {
        
        super.setUp()
        
        //get the storyboard the ViewController under test is inside
        let storyboard: UIStoryboard = UIStoryboard(name: "Main_iPhone", bundle: nil)
        
        //get the ViewController we want to test from the storyboard (note the identifier is the id explicitly set in the identity inspector)
        systemUnderTest = storyboard.instantiateViewControllerWithIdentifier("ViewController") as! PlaceListViewController
        
        //load view hierarchy
        _ = systemUnderTest.view
    }
    
    override func tearDown() {
        // Put teardown code here. This method is called after the invocation of each test method in the class.
        super.tearDown()
    }
    
    // navigation bar
    
    func testSUT_HidesBackBarButton() {
        
        XCTAssertTrue(systemUnderTest.navigationItem.hidesBackButton)
    }
    
    func testSUT_HasTitleView() {
        
        XCTAssertNotNil(systemUnderTest.navigationItem.titleView)
    }
    
    func testSUT_HasTitleView_NamedPlaces() {
        
        let centerView = systemUnderTest.navigationItem.titleView
        for subview in centerView!.subviews as [UIView] {
            
            if let label = subview as? UILabel {
                
                XCTAssertEqual(label.text, "Places")
            }
        }
    }
    
    func testSUT_HasRightBarButtonItem() {
        
        XCTAssertNotNil(self.systemUnderTest.navigationItem.rightBarButtonItem)
    }
    
    func testSUT_HasRightBarButtonItem_WithTarget_CorrectlyAssigned() {
        
        if let rightBarButtonItem = self.systemUnderTest.navigationItem.rightBarButtonItem {
            
            XCTAssertNotNil(rightBarButtonItem.target)
            XCTAssert(rightBarButtonItem.target === self.systemUnderTest)
        }
        else {
            
            XCTAssertTrue(false)
        }
    }
    
    func testSUT_HasRightBarButtonItem_WithActionMethod_CorrectlyAssigned() {
        
        if let rightBarButtonItem = self.systemUnderTest.navigationItem.rightBarButtonItem {
            
            XCTAssertTrue(rightBarButtonItem.action.description == "handleRightBarButtonTap:")
        }
        else {
            
            XCTAssertTrue(false)
        }
    }
    
    func testSUT_CanDismissViewController_WhenRightBarButtonTapped() {
        
        class MockNavigationController: UINavigationController {
            
            var popViewControllerIsCalled = false
            override private func popViewControllerAnimated(animated: Bool) -> UIViewController? {
                
                popViewControllerIsCalled = true
                
                return UIViewController()
            }
        }
        
        // set up the SUT as the root view controller of the mocked UINavigationController
        let mockNavigationController = MockNavigationController()
        mockNavigationController.setViewControllers([systemUnderTest], animated: false)
        
        // simulate the user tapping the 'Cancel' right bar button item
        systemUnderTest.handleRightBarButtonTap(UIBarButtonItem())
        
        // confirm that the parent UINavigationController pops the SUT from the navigation stack 
        XCTAssertEqual(mockNavigationController.popViewControllerIsCalled, true)
    }
}