dartpad_codelabs: Convert into Flutter project for lints in CI (flu…

…tter#260)

dartpad_codelabs/analysis_options.yaml

@@ -0,0 +1,9 @@
+include: ../analysis_options.yaml
+
+analyzer:
+  strong-mode:
+    implicit-dynamic: true
+
+linter:
+  rules:
+    avoid_print: false

dartpad_codelabs/pubspec.lock

@@ -0,0 +1,160 @@
+# Generated by pub
+# See https://dart.dev/tools/pub/glossary#lockfile
+packages:
+  async:
+    dependency: transitive
+    description:
+      name: async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.8.2"
+  boolean_selector:
+    dependency: transitive
+    description:
+      name: boolean_selector
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  characters:
+    dependency: transitive
+    description:
+      name: characters
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  charcode:
+    dependency: transitive
+    description:
+      name: charcode
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.1"
+  clock:
+    dependency: transitive
+    description:
+      name: clock
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0"
+  collection:
+    dependency: transitive
+    description:
+      name: collection
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.15.0"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  flutter:
+    dependency: "direct main"
+    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: "1.0.4"
+  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:
+      name: matcher
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.12.11"
+  meta:
+    dependency: transitive
+    description:
+      name: meta
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.7.0"
+  path:
+    dependency: transitive
+    description:
+      name: path
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.8.0"
+  sky_engine:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.99"
+  source_span:
+    dependency: transitive
+    description:
+      name: source_span
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.8.1"
+  stack_trace:
+    dependency: transitive
+    description:
+      name: stack_trace
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.10.0"
+  stream_channel:
+    dependency: transitive
+    description:
+      name: stream_channel
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.0"
+  string_scanner:
+    dependency: transitive
+    description:
+      name: string_scanner
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.1.0"
+  term_glyph:
+    dependency: transitive
+    description:
+      name: term_glyph
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.2.0"
+  test_api:
+    dependency: transitive
+    description:
+      name: test_api
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.4.3"
+  typed_data:
+    dependency: transitive
+    description:
+      name: typed_data
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "1.3.0"
+  vector_math:
+    dependency: transitive
+    description:
+      name: vector_math
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "2.1.1"
+sdks:
+  dart: ">=2.15.1 <3.0.0"

dartpad_codelabs/pubspec.yaml

@@ -0,0 +1,19 @@
+name: dartpad_codelabs
+description: A new Flutter project.
+publish_to: 'none'
+version: 1.0.0+1
+
+environment:
+  sdk: ">=2.15.1 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+  flutter_lints: ^1.0.0
+
+flutter:
+  uses-material-design: true

dartpad_codelabs/src/example_flutter/step_01/snippet.dart

@@ -2,11 +2,16 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// TODO: Remove the following line
+// ignore_for_file: unused_field, prefer_const_literals_to_create_immutables
+
 import 'package:flutter/material.dart';
 
-void main() => runApp(MyApp());
+void main() => runApp(const MyApp());
 
 class MyApp extends StatelessWidget {
+  const MyApp({Key? key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
@@ -15,13 +20,13 @@ class MyApp extends StatelessWidget {
       theme: ThemeData(
         primarySwatch: Colors.blue,
       ),
-      home: MyHomePage(title: 'Flutter Demo Home Page'),
+      home: const MyHomePage(title: 'Flutter Demo Home Page'),
     );
   }
 }
 
 class MyHomePage extends StatefulWidget {
-  MyHomePage({Key? key, required this.title}) : super(key: key);
+  const MyHomePage({Key? key, required this.title}) : super(key: key);
 
   final String title;
 
@@ -47,15 +52,15 @@ class _MyHomePageState extends State<MyHomePage> {
       body: Center(
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
+          children: [
             // Add Code Here
           ],
         ),
       ),
       floatingActionButton: FloatingActionButton(
         onPressed: _incrementCounter,
         tooltip: 'Increment',
-        child: Icon(Icons.add),
+        child: const Icon(Icons.add),
       ),
     );
   }

dartpad_codelabs/src/example_flutter/step_01/solution.dart

@@ -4,9 +4,11 @@
 
 import 'package:flutter/material.dart';
 
-void main() => runApp(MyApp());
+void main() => runApp(const MyApp());
 
 class MyApp extends StatelessWidget {
+  const MyApp({Key? key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     return MaterialApp(
@@ -15,13 +17,13 @@ class MyApp extends StatelessWidget {
       theme: ThemeData(
         primarySwatch: Colors.blue,
       ),
-      home: MyHomePage(title: 'Flutter Demo Home Page'),
+      home: const MyHomePage(title: 'Flutter Demo Home Page'),
     );
   }
 }
 
 class MyHomePage extends StatefulWidget {
-  MyHomePage({Key? key, required this.title}) : super(key: key);
+  const MyHomePage({Key? key, required this.title}) : super(key: key);
 
   final String title;
 
@@ -47,8 +49,8 @@ class _MyHomePageState extends State<MyHomePage> {
       body: Center(
         child: Column(
           mainAxisAlignment: MainAxisAlignment.center,
-          children: <Widget>[
-            Text(
+          children: [
+            const Text(
               'You have pushed the button this many times:',
             ),
             Text(
@@ -61,7 +63,7 @@ class _MyHomePageState extends State<MyHomePage> {
       floatingActionButton: FloatingActionButton(
         onPressed: _incrementCounter,
         tooltip: 'Increment',
-        child: Icon(Icons.add),
+        child: const Icon(Icons.add),
       ),
     );
   }

dartpad_codelabs/src/example_flutter/step_02/snippet.dart

@@ -2,9 +2,11 @@ import 'package:flutter/material.dart';
 
 const hostingUrl = 'https://dartpad-workshops-io2021.web.app';
 
-void main() => runApp(MyApp());
+void main() => runApp(const MyApp());
 
 class MyApp extends StatelessWidget {
+  const MyApp({Key? key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     var title = 'Web Images';

dartpad_codelabs/src/getting_started_with_slivers/step_01/snippet.dart

@@ -1,10 +1,12 @@
 import 'package:flutter/material.dart';
 
 void main() {
-  runApp(HorizonsApp());
+  runApp(const HorizonsApp());
 }
 
 class HorizonsApp extends StatelessWidget {
+  const HorizonsApp({Key? key}) : super(key: key);
+
   // This widget is the root of your application.
   @override
   Widget build(BuildContext context) {
@@ -22,16 +24,18 @@ class HorizonsApp extends StatelessWidget {
       title: 'Horizons Weather',
       home: Scaffold(
         appBar: AppBar(
-          title: Text('Horizons'),
+          title: const Text('Horizons'),
           backgroundColor: Colors.teal[800],
         ),
-        body: WeeklyForecastList(),
+        body: const WeeklyForecastList(),
       ),
     );
   }
 }
 
 class WeeklyForecastList extends StatelessWidget {
+  const WeeklyForecastList({Key? key}) : super(key: key);
+
   @override
   Widget build(BuildContext context) {
     final DateTime currentDate = DateTime.now();
@@ -40,7 +44,7 @@ class WeeklyForecastList extends StatelessWidget {
 
     return SingleChildScrollView(
       child: Column(
-        children: forecasts.map((DailyForecast dailyForecast) {
+        children: forecasts.map((dailyForecast) {
           return Card(
             child: ListTile(
               leading: Text(