Migrate to null safety

Author: mvanbeusekom

packages/url_launcher/url_launcher/example/lib/main.dart

@@ -27,15 +27,15 @@ class MyApp extends StatelessWidget {
 }
 
 class MyHomePage extends StatefulWidget {
-  MyHomePage({Key key, this.title}) : super(key: key);
+  MyHomePage({Key? key, required this.title}) : super(key: key);
   final String title;
 
   @override
   _MyHomePageState createState() => _MyHomePageState();
 }
 
 class _MyHomePageState extends State<MyHomePage> {
-  Future<void> _launched;
+  late Future<void> _launched;
   String _phone = '';
 
   Future<void> _launchInBrowser(String url) async {

packages/url_launcher/url_launcher/example/pubspec.yaml

@@ -12,9 +12,14 @@ dev_dependencies:
     path: ../../../integration_test
   flutter_driver:
     sdk: flutter
-  pedantic: ^1.8.0
+  pedantic: ^1.10.0-nullsafety.1
   mockito: ^4.1.1
-  plugin_platform_interface: ^1.0.0
+  # TODO (mvanbeusekom): Update to use pub.dev once 1.10.0-nullsafety released.
+  plugin_platform_interface:
+    git: 
+      url: https://github.com/flutter/plugins.git
+      ref: nnbd
+      path: packages/plugin_platform_interface
 
 flutter:
   uses-material-design: true

packages/url_launcher/url_launcher/lib/url_launcher.dart

@@ -59,16 +59,15 @@ import 'package:url_launcher_platform_interface/url_launcher_platform_interface.
 /// is set to true and the universal link failed to launch.
 Future<bool> launch(
   String urlString, {
-  bool forceSafariVC,
-  bool forceWebView,
-  bool enableJavaScript,
-  bool enableDomStorage,
-  bool universalLinksOnly,
-  Map<String, String> headers,
-  Brightness statusBarBrightness,
-  String webOnlyWindowName,
+  bool forceSafariVC = true,
+  bool forceWebView = false,
+  bool enableJavaScript = false,
+  bool enableDomStorage = false,
+  bool universalLinksOnly = false,
+  Map<String, String> headers = const <String, String>{},
+  Brightness? statusBarBrightness,
+  String? webOnlyWindowName,
 }) async {
-  assert(urlString != null);
   final Uri url = Uri.parse(urlString.trimLeft());
   final bool isWebURL = url.scheme == 'http' || url.scheme == 'https';
   if ((forceSafariVC == true || forceWebView == true) && !isWebURL) {
@@ -81,29 +80,32 @@ Future<bool> launch(
   /// [true] so that ui is automatically computed if [statusBarBrightness] is set.
   bool previousAutomaticSystemUiAdjustment = true;
   if (statusBarBrightness != null &&
-      defaultTargetPlatform == TargetPlatform.iOS) {
+      defaultTargetPlatform == TargetPlatform.iOS &&
+      WidgetsBinding.instance != null) {
     previousAutomaticSystemUiAdjustment =
-        WidgetsBinding.instance.renderView.automaticSystemUiAdjustment;
-    WidgetsBinding.instance.renderView.automaticSystemUiAdjustment = false;
+        WidgetsBinding.instance!.renderView.automaticSystemUiAdjustment;
+    WidgetsBinding.instance!.renderView.automaticSystemUiAdjustment = false;
     SystemChrome.setSystemUIOverlayStyle(statusBarBrightness == Brightness.light
         ? SystemUiOverlayStyle.dark
         : SystemUiOverlayStyle.light);
   }
+
   final bool result = await UrlLauncherPlatform.instance.launch(
     urlString,
-    useSafariVC: forceSafariVC ?? isWebURL,
-    useWebView: forceWebView ?? false,
-    enableJavaScript: enableJavaScript ?? false,
-    enableDomStorage: enableDomStorage ?? false,
-    universalLinksOnly: universalLinksOnly ?? false,
-    headers: headers ?? <String, String>{},
+    useSafariVC: forceSafariVC,
+    useWebView: forceWebView,
+    enableJavaScript: enableJavaScript,
+    enableDomStorage: enableDomStorage,
+    universalLinksOnly: universalLinksOnly,
+    headers: headers,
     webOnlyWindowName: webOnlyWindowName,
   );
-  assert(previousAutomaticSystemUiAdjustment != null);
-  if (statusBarBrightness != null) {
-    WidgetsBinding.instance.renderView.automaticSystemUiAdjustment =
+
+  if (statusBarBrightness != null && WidgetsBinding.instance != null) {
+    WidgetsBinding.instance!.renderView.automaticSystemUiAdjustment =
         previousAutomaticSystemUiAdjustment;
   }
+
   return result;
 }
 
@@ -115,9 +117,6 @@ Future<bool> launch(
 /// For more information see the [Managing package visibility](https://developer.android.com/training/basics/intents/package-visibility)
 /// article in the Android docs.
 Future<bool> canLaunch(String urlString) async {
-  if (urlString == null) {
-    return false;
-  }
   return await UrlLauncherPlatform.instance.canLaunch(urlString);
 }
 

packages/url_launcher/url_launcher/pubspec.yaml

@@ -2,7 +2,7 @@ name: url_launcher
 description: Flutter plugin for launching a URL on Android and iOS. Supports
   web, phone, SMS, and email schemes.
 homepage: https://github.com/flutter/plugins/tree/master/packages/url_launcher/url_launcher
-version: 5.7.2
+version: 5.8.0-nullsafety
 
 flutter:
   plugin:
@@ -24,25 +24,33 @@ flutter:
 dependencies:
   flutter:
     sdk: flutter
-  url_launcher_platform_interface: ^1.0.8
+  # TODO(mvanbeusekom): Update to use pub.dev once null safety version is published.
+  url_launcher_platform_interface: 
+    path: ../url_launcher_platform_interface
   # The design on https://flutter.dev/go/federated-plugins was to leave
   # this constraint as "any". We cannot do it right now as it fails pub publish
   # validation, so we set a ^ constraint.
   # TODO(amirh): Revisit this (either update this part in the  design or the pub tool).
   # https://github.com/flutter/flutter/issues/46264
-  url_launcher_web: ^0.1.3
+  url_launcher_web:
+    path: ../url_launcher_web
   url_launcher_linux: ^0.0.1
   url_launcher_macos: ^0.0.1
   url_launcher_windows: ^0.0.1
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  test: ^1.3.0
+  test: ^1.10.0-nullsafety.1
   mockito: ^4.1.1
-  plugin_platform_interface: ^1.0.0
-  pedantic: ^1.8.0
+  # TODO (mvanbeusekom): Update to use pub.dev once 1.10.0-nullsafety released.
+  plugin_platform_interface:
+    git: 
+      url: https://github.com/flutter/plugins.git
+      ref: nnbd
+      path: packages/plugin_platform_interface
+  pedantic: ^1.10.0-nullsafety.1
 
 environment:
-  sdk: ">=2.1.0 <3.0.0"
+  sdk: ">=2.10.0-56.0.dev <3.0.0"
   flutter: ">=1.12.13+hotfix.5 <2.0.0"

packages/url_launcher/url_launcher/test/url_launcher_test.dart

@@ -6,7 +6,10 @@
 
 import 'dart:async';
 import 'dart:ui';
+
 import 'package:flutter_test/flutter_test.dart';
+// TODO(mvanbeusekom): Remove once Mockito is migrated to null safety.
+// @dart = 2.9
 import 'package:mockito/mockito.dart';
 import 'package:flutter/foundation.dart';
 import 'package:plugin_platform_interface/plugin_platform_interface.dart';
@@ -41,10 +44,6 @@ void main() {
     });
   });
   group('launch', () {
-    test('requires a non-null urlString', () {
-      expect(() => launch(null), throwsAssertionError);
-    });
-
     test('default behavior', () async {
       await launch('http://flutter.dev/');
       expect(

packages/url_launcher/url_launcher_web/pubspec.yaml

@@ -14,7 +14,9 @@ flutter:
         fileName: url_launcher_web.dart
 
 dependencies:
-  url_launcher_platform_interface: ^1.0.8
+  # TODO(mvanbeusekom): Update to use pub.dev once null safety version is published.
+  url_launcher_platform_interface: 
+    path: ../url_launcher_platform_interface
   flutter:
     sdk: flutter
   flutter_web_plugins:
@@ -24,7 +26,9 @@ dependencies:
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  url_launcher: ^5.2.5
+  # TODO(mvanbeusekom): Update to use pub.dev once null safety version is published.
+  url_launcher:
+    path: ../url_launcher
   pedantic: ^1.8.0
   mockito: ^4.1.1
   integration_test: