Add flutter_lints to ios_app_clip (#824)

ios_app_clip/analysis_options.yaml

@@ -0,0 +1,19 @@
+include: package:flutter_lints/flutter.yaml
+
+analyzer:
+  strong-mode:
+    implicit-casts: false
+    implicit-dynamic: false
+
+linter:
+  rules:
+    avoid_types_on_closure_parameters: true
+    avoid_void_async: true
+    cancel_subscriptions: true
+    close_sinks: true
+    directives_ordering: true
+    package_api_docs: true
+    package_prefixed_library_names: true
+    test_types_in_equals: true
+    throw_in_finally: true
+    unnecessary_statements: true

ios_app_clip/lib/main.dart

@@ -7,12 +7,14 @@ import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 
 void main() {
-  runApp(Demo());
+  runApp(const Demo());
 }
 
 // The same content is shown for both the main app target and in the App
 // Clip.
 class Demo extends StatefulWidget {
+  const Demo({Key key}) : super(key: key);
+
   @override
   State<StatefulWidget> createState() => _DemoState();
 }
@@ -22,7 +24,7 @@ class _DemoState extends State<Demo> {
 
   @override
   void initState() {
-    DeviceInfoPlugin().iosInfo.then((IosDeviceInfo info) {
+    DeviceInfoPlugin().iosInfo.then((info) {
       setState(() {
         deviceInfo = '${info.name} on ${info.systemName} version '
             '${info.systemVersion}';
@@ -35,7 +37,7 @@ class _DemoState extends State<Demo> {
   Widget build(BuildContext context) {
     return CupertinoApp(
       home: CupertinoPageScaffold(
-        navigationBar: CupertinoNavigationBar(
+        navigationBar: const CupertinoNavigationBar(
           middle: Text('App Clip'),
         ),
         child: Center(
@@ -43,8 +45,8 @@ class _DemoState extends State<Demo> {
             mainAxisAlignment: MainAxisAlignment.center,
             children: <Widget>[
               Text(deviceInfo),
-              Padding(padding: EdgeInsets.only(top: 18)),
-              FlutterLogo(size: 128),
+              const Padding(padding: EdgeInsets.only(top: 18)),
+              const FlutterLogo(size: 128),
             ],
           ),
         ),

ios_app_clip/pubspec.lock

@@ -76,11 +76,25 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_lints:
+    dependency: "direct dev"
+    description:
+      name: flutter_lints
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.3"
   flutter_test:
     dependency: "direct dev"
     description: flutter
     source: sdk
     version: "0.0.0"
+  lints:
+    dependency: transitive
+    description:
+      name: lints
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.0.1"
   matcher:
     dependency: transitive
     description:

ios_app_clip/pubspec.yaml

@@ -1,7 +1,7 @@
 name: ios_app_clip
 description: An example Flutter project that can build as an App Clip.
 
-publish_to: 'none' # Remove this line if you wish to publish to pub.dev
+publish_to: "none" # Remove this line if you wish to publish to pub.dev
 
 version: 1.0.0+1
 
@@ -13,10 +13,11 @@ dependencies:
     sdk: flutter
 
   cupertino_icons: ^1.0.0
-  device_info: '>=0.4.2+7 <2.0.0'
+  device_info: ">=0.4.2+7 <2.0.0"
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
+  flutter_lints: ^1.0.0
 
 flutter:

ios_app_clip/test/widget_test.dart

@@ -15,9 +15,9 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:ios_app_clip/main.dart';
 
 void main() {
-  testWidgets('Smoke test', (WidgetTester tester) async {
+  testWidgets('Smoke test', (tester) async {
     // Build our app and trigger a frame.
-    await tester.pumpWidget(Demo());
+    await tester.pumpWidget(const Demo());
 
     expect(find.byType(FlutterLogo), findsOneWidget);
   });