Sample Unit Tests: Testing UIRightBarButtonItem has correct custom UIImage when toggled

Sample Unit Tests: Testing UIRightBarButtonItem has correct custom UIImage when toggled

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! ViewController
        
        //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()
    }
    
    func testSUT_HasRightBarButtonImage_WithCorrectDefaultCustomImage() {
        
        let defaultImage = systemUnderTest.dropDownButton.image
        XCTAssert(defaultImage == UIImage(named: "Arrow_down"))
    }
    
    func testSUT_HasRightBarButtonImage_WithCorrectCustomImageAfterToggle() {
        
        // invoke action method of rightbarbuttonitem - which toggles the image
        //systemUnderTest.performSelector(#selector(systemUnderTest.toggleRightBarButtonItemImage))
        systemUnderTest.toggleRightBarButtonItemImage(UIButton())
        
        let rightBarButtonImage = systemUnderTest.dropDownButton.image
        XCTAssert(rightBarButtonImage == UIImage(named: "Arrow_up"))
    }
}