Sample iOS Unit Tests: Working with a ViewController composed of TableViews

Sample iOS Unit Tests: Working with a ViewController composed of TableViews

import XCTest
@testable import YourAppTargetname

class SideMenuViewControllerTest: XCTestCase {
    
    var viewControllerUnderTest: SideMenuViewController!
    
    override func setUp() {
        super.setUp()
        
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        self.viewControllerUnderTest = storyboard.instantiateViewController(withIdentifier: "SideMenuViewController") as! SideMenuViewController
        
        // in view controller, menuItems = ["one", "two", "three"]
        self.viewControllerUnderTest.loadView()
        self.viewControllerUnderTest.viewDidLoad()
    }
    
    override func tearDown() {
        // Put teardown code here. This method is called after the invocation of each test method in the class.
        super.tearDown()
    }
    
    func testHasATableView() {
        XCTAssertNotNil(viewControllerUnderTest.tableView)
    }
    
    func testTableViewHasDelegate() {
        XCTAssertNotNil(viewControllerUnderTest.tableView.delegate)
    }
    
    func testTableViewConfromsToTableViewDelegateProtocol() {
        XCTAssertTrue(viewControllerUnderTest.conforms(to: UITableViewDelegate.self))
        XCTAssertTrue(viewControllerUnderTest.responds(to: #selector(viewControllerUnderTest.tableView(_:didSelectRowAt:))))
    }
    
    func testTableViewHasDataSource() {
        XCTAssertNotNil(viewControllerUnderTest.tableView.dataSource)
    }
    
    func testTableViewConformsToTableViewDataSourceProtocol() {
        XCTAssertTrue(viewControllerUnderTest.conforms(to: UITableViewDataSource.self))
        XCTAssertTrue(viewControllerUnderTest.responds(to: #selector(viewControllerUnderTest.numberOfSections(in:))))
        XCTAssertTrue(viewControllerUnderTest.responds(to: #selector(viewControllerUnderTest.tableView(_:numberOfRowsInSection:))))
        XCTAssertTrue(viewControllerUnderTest.responds(to: #selector(viewControllerUnderTest.tableView(_:cellForRowAt:))))
    }

    func testTableViewCellHasReuseIdentifier() {
        let cell = viewControllerUnderTest.tableView(viewControllerUnderTest.tableView, cellForRowAt: IndexPath(row: 0, section: 0)) as? SideMenuTableViewCell
        let actualReuseIdentifer = cell?.reuseIdentifier
        let expectedReuseIdentifier = "SideMenuTableViewCell"
        XCTAssertEqual(actualReuseIdentifer, expectedReuseIdentifier)
    }

    func testTableCellHasCorrectLabelText() {
        let cell0 = viewControllerUnderTest.tableView(viewControllerUnderTest.tableView, cellForRowAt: IndexPath(row: 0, section: 0)) as? SideMenuTableViewCell
        XCTAssertEqual(cell0?.label.text, "one")
        
        let cell1 = viewControllerUnderTest.tableView(viewControllerUnderTest.tableView, cellForRowAt: IndexPath(row: 1, section: 0)) as? SideMenuTableViewCell
        XCTAssertEqual(cell1?.label.text, "two")
        
        let cell2 = viewControllerUnderTest.tableView(viewControllerUnderTest.tableView, cellForRowAt: IndexPath(row: 2, section: 0)) as? SideMenuTableViewCell
        XCTAssertEqual(cell2?.label.text, "three")
    }
}

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