swift - NSInternalInconsistencyException 完成处理程序传递给 webView:decidePolicyForNavigationAction:decisionHandle 未被调用

Question

我在我们的一项 iOS 应用测试中遇到了问题。非常感谢任何解决问题的帮助！

测试代码：

    func testOpenExternalBrowser_for_valid_urls() {
    // Given
    let vc = MockDashboardViewController()
    vc.openInternalBrowserCalled = false
    vc.openExternalBrowserCalled = false
    vc.webview = WKWebView()
    vc.webview.navigationDelegate = vc

    // When
    let url = URL.init(string: "https://example.com/restOfUrl")
    XCTAssertTrue(url!.absoluteString.contains("https://example.com"), "initial url string is wrong")
    vc.webview.load(URLRequest(url: url!));
    waitSeconds(duration: 2)

    // Then
    XCTAssertFalse(vc.openExternalBrowserCalled, "openExternalBrowserCalled value is wrong")
    XCTAssertTrue(vc.openInternalBrowserCalled, "openInternalBrowserCalled value is wrong")
}

这给了我错误：

错误：-[Tests.ViewControllerTests testOpenExternalBrowser_for_valid_urls]：失败：捕获“NSInternalInconsistencyException”，“传递给-[ViewController webView:decidePolicyForNavigationAction:decisionHandler:] 的完成处理程序没有被调用”

这是相关的 WKWebKit ViewController 代码：

    // MARK: WKNavigationDelegate methods
func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
    guard let url = navigationAction.request.url, let urlScheme = url.scheme, let urlHost = url.host else {
        //if we can't convert the URL, deny the action
        decisionHandler(WKNavigationActionPolicy.cancel);
        return;
    }

    var isPortValid = false;
    if let urlPort = url.port {
        isPortValid = urlPort == HostDefinitions.PORT;
    } else {
        isPortValid = urlScheme == DashboardConstants.HTTPS;
    }

    if(isPortValid && urlScheme == HostDefinitions.SCHEME && urlHost.compare(HostDefinitions.HOST) == ComparisonResult.orderedSame) {
        openInternalBrowser(url: url, decisionHandler: decisionHandler)
        return;
    }

    decisionHandler(WKNavigationActionPolicy.cancel);
    openExternalBrowser(url: url)
}

func openInternalBrowser(url: URL, decisionHandler:@escaping (WKNavigationActionPolicy) -> Void) {
    if(url.path == PathDefinitions.Login) {
        //the user has logged out or visited the login page. We will now de-auth them and direct them back to the login page
        OperationQueue.main.addOperation {
            AuthManager.logout()
            _ = self.navigationController?.popToRootViewController(animated: true);
        }
        decisionHandler(WKNavigationActionPolicy.cancel);
    } else {
        decisionHandler(WKNavigationActionPolicy.allow);
    }
}

func openExternalBrowser(url: URL) {
    AppManager.openExternalBrowser(url: url)
}

有任何想法吗？我尝试添加一个 return 语句并将决策处理程序添加到函数 openExternalBrowser 但都不起作用。应用程序正常运行（在 Safari 中打开外部 URL），但测试失败。

谢谢！

编辑： 这是 MockDashboardViewController 代码：

class MockDashboardViewController: DashboardViewController {

    var openInternalBrowserCalled = false
    var openExternalBrowserCalled = false

    var presentNotificationCalled = false

    var webviewURLString = ""

    override func openInternalBrowser(url: URL, decisionHandler:@escaping (WKNavigationActionPolicy) -> Void) {
        openInternalBrowserCalled = true
    }

    override func openExternalBrowser(url: URL) {
        openExternalBrowserCalled = true
    }

    override func presentNotification(notification: DashboardNotification, showAlertView: Bool) {
        presentNotificationCalled = true
    }
}

标签： swiftwkwebview

Answer 1

错误信息是正确的。你是说：

let vc = MockDashboardViewController()
vc.webview.navigationDelegate = vc

所以web视图的导航不是你的“相关的WKWebKit ViewController”，我假设它是一个DashboardViewController，而是DashboardViewController的一个子类，即MockDashboardViewController。它说：

override func openInternalBrowser(url: URL, decisionHandler:@escaping (WKNavigationActionPolicy) -> Void) {
    openInternalBrowserCalled = true
}

好的，那么当decidePolicyFor被调用时会发生什么？在 MockDashboardViewController 中没有实现，所以调用 DashboardViewController 的实现：

func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
    if(isPortValid && urlScheme == HostDefinitions.SCHEME && urlHost.compare(HostDefinitions.HOST) == ComparisonResult.orderedSame) {
        openInternalBrowser(url: url, decisionHandler: decisionHandler)
        return;
    }
}

这就是沿着执行路径发生的所有事情。现在，这一切都在哪里decisionHandler？无处。运行时是完全正确的。

确实decisionHandler会在 DashboardViewController 的openInternalBrowser(url:decisionHandler:). 这就是为什么当您运行应用程序（而不是测试）时应用程序运行良好的原因。但是在你的测试子类中，你覆盖了它——你没有调用super，所以你把那些调用扔到了decisionHandler.