[url_launcher] Update for UIScene compatibility

packages/url_launcher/url_launcher_ios/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 6.4.0
+
+* Improves compatibility with `UIScene`.
+* Updates minimum supported SDK version to Flutter 3.38/Dart 3.10.
+
 ## 6.3.6
 
 * Updates to Pigeon 26.

packages/url_launcher/url_launcher_ios/example/ios/RunnerTests/URLLauncherTests.swift

@@ -13,15 +13,32 @@ private func urlParsingIsStrict() -> Bool {
   return URL(string: "b a d U R L") == nil
 }
 
-final class URLLauncherTests: XCTestCase {
+final class TestViewPresenter: ViewPresenter {
+  public var presentedController: UIViewController?
 
-  private func createPlugin() -> URLLauncherPlugin {
-    let launcher = FakeLauncher()
-    return URLLauncherPlugin(launcher: launcher)
+  func present(
+    _ viewControllerToPresent: UIViewController, animated: Bool, completion: (() -> Void)? = nil
+  ) {
+    presentedController = viewControllerToPresent
+  }
+}
+
+final class StubViewPresenterProvider: ViewPresenterProvider {
+  var viewPresenter: ViewPresenter?
+
+  init(viewPresenter: ViewPresenter?) {
+    self.viewPresenter = viewPresenter
   }
+}
+
+final class URLLauncherTests: XCTestCase {
 
-  private func createPlugin(launcher: FakeLauncher) -> URLLauncherPlugin {
-    return URLLauncherPlugin(launcher: launcher)
+  private func createPlugin(
+    launcher: FakeLauncher = FakeLauncher(), viewPresenter: ViewPresenter? = TestViewPresenter()
+  ) -> URLLauncherPlugin {
+    return URLLauncherPlugin(
+      launcher: launcher,
+      viewPresenterProvider: StubViewPresenterProvider(viewPresenter: viewPresenter))
   }
 
   func testCanLaunchSuccess() {
@@ -133,7 +150,8 @@ final class URLLauncherTests: XCTestCase {
 
   func testLaunchSafariViewControllerWithClose() {
     let launcher = FakeLauncher()
-    let plugin = createPlugin(launcher: launcher)
+    let viewPresenter = TestViewPresenter()
+    let plugin = createPlugin(launcher: launcher, viewPresenter: viewPresenter)
 
     let expectation = XCTestExpectation(description: "completion called")
     plugin.openUrlInSafariViewController(url: "https://flutter.dev") { result in
@@ -147,6 +165,23 @@ final class URLLauncherTests: XCTestCase {
     }
     plugin.closeSafariViewController()
     wait(for: [expectation], timeout: 30)
+    XCTAssertNotNil(viewPresenter.presentedController)
+  }
+
+  func testLaunchSafariViewControllerFailureWithNoViewPresenter() {
+    let expectation = XCTestExpectation(description: "completion called")
+    createPlugin(viewPresenter: nil).openUrlInSafariViewController(url: "https://flutter.dev") {
+      result in
+      switch result {
+      case .success(let details):
+        XCTAssertEqual(details, .noUI)
+      case .failure(let error):
+        XCTFail("Unexpected error: \(error)")
+      }
+      expectation.fulfill()
+    }
+
+    wait(for: [expectation], timeout: 1)
   }
 
 }

packages/url_launcher/url_launcher_ios/example/pubspec.yaml

@@ -3,8 +3,8 @@ description: Demonstrates how to use the url_launcher plugin.
 publish_to: none
 
 environment:
-  sdk: ^3.9.0
-  flutter: ">=3.35.0"
+  sdk: ^3.10.0
+  flutter: ">=3.38.0"
 
 dependencies:
   flutter:

packages/url_launcher/url_launcher_ios/ios/url_launcher_ios/Sources/url_launcher_ios/URLLauncherPlugin.swift

@@ -8,22 +8,20 @@ import UIKit
 public final class URLLauncherPlugin: NSObject, FlutterPlugin, UrlLauncherApi {
 
   public static func register(with registrar: FlutterPluginRegistrar) {
-    let plugin = URLLauncherPlugin()
+    let plugin = URLLauncherPlugin(
+      viewPresenterProvider: DefaultViewPresenterProvider(registrar: registrar))
     UrlLauncherApiSetup.setUp(binaryMessenger: registrar.messenger(), api: plugin)
     registrar.publish(plugin)
   }
 
   private var currentSession: URLLaunchSession?
   private let launcher: Launcher
+  /// The view presenter provider, for showing a Safari view controller.
+  private let viewPresenterProvider: ViewPresenterProvider
 
-  private var topViewController: UIViewController? {
-    // TODO(stuartmorgan) Provide a non-deprecated codepath. See
-    // https://github.com/flutter/flutter/issues/104117
-    UIApplication.shared.keyWindow?.rootViewController?.topViewController
-  }
-
-  init(launcher: Launcher = DefaultLauncher()) {
+  init(launcher: Launcher = DefaultLauncher(), viewPresenterProvider: ViewPresenterProvider) {
     self.launcher = launcher
+    self.viewPresenterProvider = viewPresenterProvider
   }
 
   func canLaunchUrl(url: String) -> LaunchResult {
@@ -58,43 +56,21 @@ public final class URLLauncherPlugin: NSObject, FlutterPlugin, UrlLauncherApi {
       return
     }
 
+    guard let presenter = viewPresenterProvider.viewPresenter else {
+      completion(.success(.noUI))
+      return
+    }
+
     let session = URLLaunchSession(url: url, completion: completion)
     currentSession = session
 
     session.didFinish = { [weak self] in
       self?.currentSession = nil
     }
-    topViewController?.present(session.safariViewController, animated: true, completion: nil)
+    presenter.present(session.safariViewController, animated: true, completion: nil)
   }
 
   func closeSafariViewController() {
     currentSession?.close()
   }
 }
-
-/// This method recursively iterates through the view hierarchy
-/// to return the top-most view controller.
-///
-/// It supports the following scenarios:
-///
-/// - The view controller is presenting another view.
-/// - The view controller is a UINavigationController.
-/// - The view controller is a UITabBarController.
-///
-/// @return The top most view controller.
-extension UIViewController {
-  var topViewController: UIViewController {
-    if let navigationController = self as? UINavigationController {
-      return navigationController.viewControllers.last?.topViewController
-        ?? navigationController
-        .visibleViewController ?? navigationController
-    }
-    if let tabBarController = self as? UITabBarController {
-      return tabBarController.selectedViewController?.topViewController ?? tabBarController
-    }
-    if let presented = presentedViewController {
-      return presented.topViewController
-    }
-    return self
-  }
-}

packages/url_launcher/url_launcher_ios/ios/url_launcher_ios/Sources/url_launcher_ios/ViewPresenter.swift

@@ -0,0 +1,44 @@
+// Copyright 2013 The Flutter Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import Flutter
+import UIKit
+
+/// Protocol for UIViewController methods relating to presenting a controller.
+///
+/// This protocol exists to allow injecting an alternate implementation for testing.
+protocol ViewPresenter {
+  /// Presents a view controller modally.
+  func present(
+    _ viewControllerToPresent: UIViewController,
+    animated flag: Bool,
+    completion: (() -> Void)?
+  )
+}
+
+/// ViewPresenter is intentionally a direct passthroguh to UIViewController.
+extension UIViewController: ViewPresenter {}
+
+/// Protocol for FlutterPluginRegistrar method for accessing the view controller.
+///
+/// This is necessary because Swift doesn't allow for only partially implementing a protocol, so
+/// a stub implementation of FlutterPluginRegistrar for tests would break any time something was
+/// added to that protocol.
+protocol ViewPresenterProvider {
+  /// Returns the view presenter associated with the Flutter content.
+  var viewPresenter: ViewPresenter? { get }
+}
+
+/// Non-test implementation of ViewPresenterProvider that forwards to the plugin registrar.
+final class DefaultViewPresenterProvider: ViewPresenterProvider {
+  private let registrar: FlutterPluginRegistrar
+
+  init(registrar: FlutterPluginRegistrar) {
+    self.registrar = registrar
+  }
+
+  var viewPresenter: ViewPresenter? {
+    registrar.viewController
+  }
+}

packages/url_launcher/url_launcher_ios/ios/url_launcher_ios/Sources/url_launcher_ios/messages.g.swift

@@ -85,8 +85,10 @@ enum InAppLoadResult: Int {
   case failedToLoad = 1
   /// The URL could not be launched because it is invalid.
   case invalidUrl = 2
+  /// The URL could not be launched because no UI is available.
+  case noUI = 3
   /// The controller was closed before loading.
-  case dismissed = 3
+  case dismissed = 4
 }
 
 private class MessagesPigeonCodecReader: FlutterStandardReader {

packages/url_launcher/url_launcher_ios/lib/src/messages.g.dart

@@ -41,6 +41,9 @@ enum InAppLoadResult {
   /// The URL could not be launched because it is invalid.
   invalidUrl,
 
+  /// The URL could not be launched because no UI is available.
+  noUI,
+
   /// The controller was closed before loading.
   dismissed,
 }

packages/url_launcher/url_launcher_ios/lib/url_launcher_ios.dart

@@ -148,6 +148,8 @@ class UrlLauncherIOS extends UrlLauncherPlatform {
         throw _failedSafariViewControllerLoadException(url);
       case InAppLoadResult.invalidUrl:
         throw _invalidUrlException();
+      case InAppLoadResult.noUI:
+        throw _noUIException();
       case InAppLoadResult.dismissed:
         return false;
     }
@@ -178,4 +180,16 @@ class UrlLauncherIOS extends UrlLauncherPlatform {
       message: 'Error while launching $url',
     );
   }
+
+  // TODO(stuartmorgan): Remove this as part of standardizing error handling.
+  // See https://github.com/flutter/flutter/issues/127665
+  //
+  // This PlatformException is designed to match the pattern of the pre-existing
+  // exceptions above.
+  PlatformException _noUIException() {
+    throw PlatformException(
+      code: 'no_ui_available',
+      message: 'No view controller available',
+    );
+  }
 }

packages/url_launcher/url_launcher_ios/pigeons/messages.dart

@@ -34,6 +34,9 @@ enum InAppLoadResult {
   /// The URL could not be launched because it is invalid.
   invalidUrl,
 
+  /// The URL could not be launched because no UI is available.
+  noUI,
+
   /// The controller was closed before loading.
   dismissed,
 }

packages/url_launcher/url_launcher_ios/pubspec.yaml

@@ -2,11 +2,11 @@ name: url_launcher_ios
 description: iOS implementation of the url_launcher plugin.
 repository: https://github.com/flutter/packages/tree/main/packages/url_launcher/url_launcher_ios
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+url_launcher%22
-version: 6.3.6
+version: 6.4.0
 
 environment:
-  sdk: ^3.9.0
-  flutter: ">=3.35.0"
+  sdk: ^3.10.0
+  flutter: ">=3.38.0"
 
 flutter:
   plugin:

packages/url_launcher/url_launcher_ios/test/url_launcher_ios_test.dart

@@ -278,6 +278,26 @@ void main() {
       );
     });
 
+    test('throws PlatformException for missing view controller', () async {
+      when(
+        api.openUrlInSafariViewController(_webUrl),
+      ).thenAnswer((_) async => InAppLoadResult.noUI);
+      final launcher = UrlLauncherIOS(api: api);
+      await expectLater(
+        launcher.launchUrl(
+          _webUrl,
+          const LaunchOptions(mode: PreferredLaunchMode.inAppWebView),
+        ),
+        throwsA(
+          isA<PlatformException>().having(
+            (PlatformException e) => e.code,
+            'code',
+            'no_ui_available',
+          ),
+        ),
+      );
+    });
+
     test('throws PlatformException for load failure', () async {
       when(
         api.openUrlInSafariViewController(_webUrl),

script/configs/exclude_xcode_deprecation.yaml

@@ -1,6 +1,2 @@
 # TODO(louisehsu): Remove deprecation check when StoreKit 2 is adopted. https://github.com/flutter/flutter/issues/116383
 - in_app_purchase_storekit
-# TODO(stuartmorgan): Remove once there's a non-deprecated codepath for getting
-# the view controller available on stable.
-# See https://github.com/flutter/flutter/issues/174415
-- url_launcher_ios