我如何断言在我的单元测试中调用了一个委托

Question

我希望根据演示者中检查的结果来调用正确的委托方法。

模拟了我的IdentityProvider以返回true，我该如何编写一个断言delegate?.userIsAuthenticated()的测试？

import Foundation
import InjectStory

protocol StartPresenterDelegate: class {
    func userIsAuthenticated()
    func userNeedsToAuthenticate()
}

class StartPresenter {
    weak var delegate: StartPresenterDelegate?
    weak var view: StartViewInterface!

    private lazy var identityProvider = Dependencies.identityProvider.inject()

    init(view: StartViewInterface) {
        self.view = view
    }

    private func checkUserAuthState() {
        if identityProvider.isAuthorized() {
            delegate?.userIsAuthenticated()
        } else {
            delegate?.userNeedsToAuthenticate()
        }
    }

}

extension StartPresenter: StartPresentation {
    func onViewDidLoad() {
        checkUserAuthState()
    }
}

extension StartPresenter {
    struct Dependencies {
        static let identityProvider = Injection<IdentityProviderProtocol>(IdentityProvider.shared)
    }
}

Answer 1

您需要做一些技巧。为您的协议StartPresenterDelegate创建MockDelegateClass例如：

class MockDelegate: StartPresenterDelegate {

    var isUserIsAuthenticatedCalled = false
    var isUserNeedsToAuthenticateCalled = false

    func userIsAuthenticated() {
        isUserIsAuthenticatedCalled = true
    }

    func userNeedsToAuthenticate() {
        isUserNeedsToAuthenticateCalled = true
    }
}

然后在测试中尝试执行类似的操作：

func test_MyTest() {
    // init your class StartPresenter that you wanna test
    var presenter = StartPresenter(...)
    var mockDelegate = MockDelegate()
    presenter.delegate = mockDelegate
    presenter.onViewDidLoad()

    XCTAssertTrue(mockDelegate.isUserIsAuthenticatedCalled)
    XCTAssertFalse(mockDelegate.isUserNeedsToAuthenticateCalled)
    // or change isUserIsAuthenticatedCalled and isUserNeedsToAuthenticateCalled if you expect another states
}

对于不同的状态，您需要不同的测试，对您来说，这将是测试委托调用的最简单方法。

Answer 2

您也必须​​如下模拟StartPresenterDelegate。

class MockStartPresenterDelegate: StartPresenterDelegate {
   var userIsAuthenticated_wasCalled = false 

   func userIsAuthenticated() {
       userIsAuthenticated_wasCalled = true
   }
}

注入MockStartPresenterDelegate作为代理，并检查userIsAuthenticated_wasCalled是否为真

Answer 3

通过这种方式，您可以确认Swift应用中代表的单元测试