Migrate to null safety (#62)

* Migrate wakelock_web

* Adjust constraint

* flutter constraint

* Finish

* Temporarily unsound

@@ -96,4 +96,4 @@ jobs:
         if: matrix.package == 'wakelock'
         run: |
           cd wakelock/example
-          flutter drive --driver=test_driver/integration_test.dart --target=integration_test/wakelock_test.dart
+          flutter drive --driver=test_driver/integration_test.dart --target=integration_test/wakelock_test.dart --no-sound-null-safety

+## 0.3.0-nullsafety.0
+
+* Migrated to null safety.
+* **Breaking**: removed deprecated `isEnabled` and `on` in `toggle`.
+
 ## 0.2.1+1
 
 * Fixed Android build warning (`import_js_library`) by bumping `wakelock_web`.

 import 'package:flutter_test/flutter_test.dart';
+
+// See https://github.com/flutter/flutter/issues/71379.
+// ignore: import_of_legacy_library_into_null_safe
 import 'package:integration_test/integration_test.dart';
 import 'package:wakelock/wakelock.dart';
 

@@ -58,16 +58,17 @@ class _WakelockExampleAppState extends State<WakelockExampleApp> {
               FutureBuilder(
                 future: Wakelock.enabled,
                 builder: (context, AsyncSnapshot<bool> snapshot) {
+                  final data = snapshot.data;
                   // The use of FutureBuilder is necessary here to await the
                   // bool value from the `enabled` getter.
-                  if (!snapshot.hasData) {
+                  if (data == null) {
                     // The Future is retrieved so fast that you will not be able
                     // to see any loading indicator.
                     return Container();
                   }
 
                   return Text('The wakelock is currently '
-                      '${snapshot.data ? 'enabled' : 'disabled'}.');
+                      '${data ? 'enabled' : 'disabled'}.');
                 },
               ),
               const Spacer(

@@ -5,7 +5,7 @@ description: >-2
 publish_to: 'none'
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: '>=2.12.0-0 <3.0.0'
 
 dependencies:
   flutter:
@@ -24,7 +24,8 @@ dev_dependencies:
     sdk: flutter
   flutter_driver:
     sdk: flutter
-  integration_test: ^0.9.1
+
+  integration_test: ^0.9.2+2
   test: any
 
-  pedantic: ^1.9.2
+  pedantic: ^1.10.0-nullsafety.3

+// See https://github.com/flutter/flutter/issues/71379.
+// ignore: import_of_legacy_library_into_null_safe
 import 'package:integration_test/integration_test_driver.dart';
 
 Future<void> main() => integrationDriver();

-import 'package:meta/meta.dart';
 import 'package:wakelock_platform_interface/wakelock_platform_interface.dart';
 
 final _wakelockPlatformInstance = WakelockPlatformInterface.instance;
@@ -53,20 +52,9 @@ class Wakelock {
   ///
   /// You can await the [Future] to wait for the operation to complete.
   static Future<void> toggle({
-    @required bool enable,
-    @Deprecated('Use the `enable` parameter instead.') bool on,
+    required bool enable,
   }) {
-    // The checks allow only `on` to be used in the case of old code and
-    // they encourage to use only `enable` instead (combined with the
-    // deprecation warning).
-    assert(enable != null || on != null,
-        'The `enable` parameter must not be null when toggling the wakelock.');
-    assert(
-        on == null || enable == null,
-        'The `on` parameter has been deprecated; '
-        'specify only the `enable` parameter instead.');
-
-    return _wakelockPlatformInstance.toggle(enable: enable ?? on);
+    return _wakelockPlatformInstance.toggle(enable: enable);
   }
 
   /// Returns whether the wakelock is currently enabled or not.
@@ -78,8 +66,4 @@ class Wakelock {
   /// bool wakelockEnabled = await Wakelock.enabled;
   /// ```
   static Future<bool> get enabled => _wakelockPlatformInstance.enabled;
-
-  /// Returns the current wakelock status.
-  @Deprecated('Use the `enabled` getter instead.')
-  static Future<bool> get isEnabled => enabled;
 }

+// This is fine because it is a dev dependency.
+// See https://github.com/flutter/flutter/issues/71360.
+// @dart=2.9
 import 'package:pigeon/pigeon.dart';
 
 /// Message for toggling the wakelock on the platform side.

@@ -2,12 +2,12 @@ name: wakelock
 description: >-2
   Plugin that allows you to keep the device screen awake, i.e. prevent the screen from sleeping on
   Android, iOS, and web.
-version: 0.2.1+1
+version: 0.3.0-nullsafety.0
 homepage: https://github.com/creativecreatorormaybenot/wakelock/tree/master/wakelock
 
 environment:
-  sdk: ">=2.8.0 <3.0.0"
-  flutter: ">=1.20.0 <2.0.0"
+  sdk: '>=2.12.0-0 <3.0.0'
+  flutter: '>=1.24.0-0 <2.0.0'
 
 dependencies:
   flutter:
@@ -15,15 +15,15 @@ dependencies:
 
   meta: ^1.2.0
 
-  wakelock_platform_interface: ^0.1.0+1
-  wakelock_web: ^0.1.0+3
+  wakelock_platform_interface: ^0.2.0-nullsafety.2
+  wakelock_web: ^0.2.0-nullsafety.0
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
 
-  pedantic: ^1.9.2
-  pigeon: ^0.1.14
+  pedantic: ^1.10.0-nullsafety.0
+  pigeon: ^0.1.15
 
 flutter:
   plugin:

@@ -6,16 +6,12 @@ void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
 
   group('$Wakelock', () {
-    FakeWakelockApi fakeWakelock;
+    late FakeWakelockApi fakeWakelock;
 
     setUpAll(() {
       fakeWakelock = FakeWakelockApi();
     });
 
-    test('toggle enable non-null assertion', () {
-      expect(() => Wakelock.toggle(enable: null), throwsAssertionError);
-    });
-
     test('enable', () async {
       await Wakelock.enable();
 
@@ -55,7 +51,7 @@ class FakeWakelockApi extends TestWakelockApi {
   }
 
   final calls = <String>[];
-  ToggleMessage toggleMessage;
+  late ToggleMessage toggleMessage;
 
   @override
   IsEnabledMessage isEnabled() {

+## 0.2.0-nullsafety.0
+
+* Migrated to null safety.
+* Temporarily removed `import_js_library` dependency and included code internally.
+
 ## 0.1.0+3
 
 * Bumped minimum `import_js_library` version in order to resolve Android build warning.

+/// Function with a single typed argument.
 typedef Func1<A, R> = R Function(A a);

+import 'dart:html' as html;
+
+/// This is an implementation of the `import_js_library` plugin that is used
+/// until that plugin is migrated to null safety.
+/// See https://github.com/florent37/flutter_web_import_js_library/pull/6#issuecomment-735349208.
+
+/// Imports a JS script file from the given [url] given the relative
+/// [flutterPluginName].
+void importJsLibrary({required String url, String? flutterPluginName}) {
+  if (flutterPluginName == null) {
+    _importJSLibraries([url]);
+  } else {
+    _importJSLibraries([_libraryUrl(url, flutterPluginName)]);
+  }
+}
+
+String _libraryUrl(String url, String pluginName) {
+  if (url.startsWith('./')) {
+    url = url.replaceFirst('./', '');
+    return './assets/packages/$pluginName/$url';
+  }
+  if (url.startsWith('assets/')) {
+    return './assets/packages/$pluginName/$url';
+  } else {
+    return url;
+  }
+}
+
+html.ScriptElement _createScriptTag(String library) {
+  final script = html.ScriptElement()
+    ..type = 'text/javascript'
+    ..charset = 'utf-8'
+    ..async = true
+    ..src = library;
+  return script;
+}
+
+/// Injects a bunch of libraries in the <head> and returns a
+/// Future that resolves when all load.
+Future<void> _importJSLibraries(List<String> libraries) {
+  final loading = <Future<void>>[];
+  final head = html.querySelector('head');
+
+  libraries.forEach((String library) {
+    if (!_isImported(library)) {
+      final scriptTag = _createScriptTag(library);
+      head!.children.add(scriptTag);
+      loading.add(scriptTag.onLoad.first);
+    }
+  });
+
+  return Future.wait(loading);
+}
+
+bool _isImported(String url) {
+  final head = html.querySelector('head')!;
+  return _isLoaded(head, url);
+}
+
+bool _isLoaded(html.Element head, String url) {
+  if (url.startsWith('./')) {
+    url = url.replaceFirst('./', '');
+  }
+  for (var element in head.children) {
+    if (element is html.ScriptElement) {
+      if (element.src.endsWith(url)) {
+        return true;
+      }
+    }
+  }
+  return false;
+}

@@ -5,7 +5,7 @@ import 'package:js/js.dart';
 import 'package:wakelock_web/src/promise.dart';
 
 /// Toggles the JS wakelock.
-external toggle(bool enable);
+external void toggle(bool enable);
 
 /// Returns a JS promise of whether the wakelock is enabled or not.
 external PromiseJsImpl<bool> enabled();

@@ -11,5 +11,5 @@ class PromiseJsImpl<T> {
   external PromiseJsImpl(Function resolver);
 
   /// Attaches callbacks to a JS promise.
-  external PromiseJsImpl then([Func1 onResolve, Func1 onReject]);
+  external PromiseJsImpl then([Func1? onResolve, Func1? onReject]);
 }

 import 'dart:async';
 
 import 'package:flutter_web_plugins/flutter_web_plugins.dart';
-import 'package:import_js_library/import_js_library.dart';
 import 'package:js/js.dart';
 import 'package:wakelock_platform_interface/wakelock_platform_interface.dart';
-import 'package:wakelock_web/src/js_wakelock.dart' as Wakelock;
+import 'package:wakelock_web/src/import_js_library.dart';
+import 'package:wakelock_web/src/js_wakelock.dart' as wakelock_web;
 
 /// The web implementation of the [WakelockPlatformInterface].
 ///
@@ -22,17 +22,15 @@ class WakelockWeb extends WakelockPlatformInterface {
   }
 
   @override
-  Future<void> toggle({bool enable}) async {
-    assert(enable != null);
-
-    Wakelock.toggle(enable);
+  Future<void> toggle({required bool enable}) async {
+    wakelock_web.toggle(enable);
   }
 
   @override
   Future<bool> get enabled async {
     final completer = Completer<bool>();
 
-    Wakelock.enabled().then(
+    wakelock_web.enabled().then(
       // onResolve
       allowInterop((value) {
         assert(value is bool);

 name: wakelock_web
 description: Web platform implementation of the wakelock_platform_interface for the wakelock plugin.
-version: 0.1.0+3
+version: 0.2.0-nullsafety.0
 homepage: https://github.com/creativecreatorormaybenot/wakelock/tree/master/wakelock_web
 
 environment:
-  sdk: ">=2.8.0 <3.0.0"
-  flutter: ">=1.20.0 <2.0.0"
+  sdk: '>=2.12.0-0 <3.0.0'
+  flutter: '>=1.24.0-0 <2.0.0'
 
 dependencies:
   flutter:
@@ -13,16 +13,15 @@ dependencies:
   flutter_web_plugins:
     sdk: flutter
 
-  import_js_library: ^1.0.2
-  js: ^0.6.2
+  js: ^0.6.3-nullsafety.0
 
-  wakelock_platform_interface: ^0.1.0
+  wakelock_platform_interface: ^0.2.0-nullsafety.2
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
 
-  pedantic: ^1.9.2
+  pedantic: ^1.10.0-nullsafety.0
 
   wakelock:
     path: ../wakelock