enable lint unnecessary_const

Author: a14n

analysis_options.yaml

@@ -120,6 +120,7 @@ linter:
     - type_init_formals
     # - unawaited_futures # https://github.com/flutter/flutter/issues/5793
     - unnecessary_brace_in_string_interps
+    - unnecessary_const
     - unnecessary_getters_setters
     # - unnecessary_lambdas # https://github.com/dart-lang/linter/issues/498
     - unnecessary_null_aware_assignments

packages/android_alarm_manager/example/lib/main.dart

@@ -73,7 +73,7 @@ Future<Null> main() async {
   final int oneShotID = 2;
   printHelloMessage("Hello, main()!");
   runApp(const Center(
-      child: const Text('Hello, world!', textDirection: TextDirection.ltr)));
+      child: Text('Hello, world!', textDirection: TextDirection.ltr)));
   await AndroidAlarmManager.periodic(
       const Duration(minutes: 1), helloAlarmID, printHello);
   await AndroidAlarmManager.periodic(

packages/android_alarm_manager/lib/android_alarm_manager.dart

@@ -13,7 +13,7 @@ import 'package:flutter/services.dart';
 class AndroidAlarmManager {
   static const String _channelName = 'plugins.flutter.io/android_alarm_manager';
   static const MethodChannel _channel =
-      const MethodChannel(_channelName, const JSONMethodCodec());
+      MethodChannel(_channelName, JSONMethodCodec());
 
   /// Schedules a one-shot timer to run `callback` after time `delay`.
   ///

packages/android_intent/example/lib/main.dart

@@ -32,8 +32,8 @@ class MyHomePage extends StatelessWidget {
   void _createAlarm() {
     final AndroidIntent intent = const AndroidIntent(
       action: 'android.intent.action.SET_ALARM',
-      arguments: const <String, dynamic>{
-        'android.intent.extra.alarm.DAYS': const <int>[2, 3, 4, 5, 6],
+      arguments: <String, dynamic>{
+        'android.intent.extra.alarm.DAYS': <int>[2, 3, 4, 5, 6],
         'android.intent.extra.alarm.HOUR': 21,
         'android.intent.extra.alarm.MINUTES': 30,
         'android.intent.extra.alarm.SKIP_UI': true,

packages/camera/example/lib/main.dart

@@ -87,7 +87,7 @@ class _CameraExampleHomeState extends State<CameraExampleHome> {
     if (controller == null || !controller.value.isInitialized) {
       return const Text(
         'Tap a camera',
-        style: const TextStyle(
+        style: TextStyle(
           color: Colors.white,
           fontSize: 24.0,
           fontWeight: FontWeight.w900,

packages/cloud_firestore/lib/src/firestore.dart

@@ -9,9 +9,9 @@ part of cloud_firestore;
 /// You can get an instance by calling [Firestore.instance].
 class Firestore {
   @visibleForTesting
-  static const MethodChannel channel = const MethodChannel(
+  static const MethodChannel channel = MethodChannel(
     'plugins.flutter.io/cloud_firestore',
-    const StandardMethodCodec(const FirestoreMessageCodec()),
+    StandardMethodCodec(FirestoreMessageCodec()),
   );
 
   static final Map<int, StreamController<QuerySnapshot>> _queryObservers =

packages/cloud_firestore/test/cloud_firestore_test.dart

@@ -18,8 +18,9 @@ void main() {
     final List<MethodCall> log = <MethodCall>[];
     CollectionReference collectionReference;
     Transaction transaction;
-    const Map<String, dynamic> kMockDocumentSnapshotData =
-        const <String, dynamic>{'1': 2};
+    const Map<String, dynamic> kMockDocumentSnapshotData = <String, dynamic>{
+      '1': 2
+    };
 
     setUp(() async {
       mockHandleId = 0;
@@ -556,7 +557,7 @@ void main() {
     });
 
     group('FirestoreMessageCodec', () {
-      const MessageCodec<dynamic> codec = const FirestoreMessageCodec();
+      const MessageCodec<dynamic> codec = FirestoreMessageCodec();
       final DateTime testTime = new DateTime(2015, 10, 30, 11, 16);
       test('should encode and decode simple messages', () {
         _checkEncodeDecode<dynamic>(codec, testTime);

packages/cloud_functions/lib/cloud_functions.dart

@@ -20,7 +20,7 @@ class CloudFunctionsException implements Exception {
 /// You can get an instance by calling [CloudFunctions.instance].
 class CloudFunctions {
   @visibleForTesting
-  static const MethodChannel channel = const MethodChannel('cloud_functions');
+  static const MethodChannel channel = MethodChannel('cloud_functions');
 
   static CloudFunctions _instance = new CloudFunctions();
 

packages/connectivity/lib/connectivity.dart

@@ -14,10 +14,10 @@ import 'package:flutter/services.dart';
 enum ConnectivityResult { wifi, mobile, none }
 
 const MethodChannel _methodChannel =
-    const MethodChannel('plugins.flutter.io/connectivity');
+    MethodChannel('plugins.flutter.io/connectivity');
 
 const EventChannel _eventChannel =
-    const EventChannel('plugins.flutter.io/connectivity_status');
+    EventChannel('plugins.flutter.io/connectivity_status');
 
 class Connectivity {
   Stream<ConnectivityResult> _onConnectivityChanged;

packages/device_info/lib/device_info.dart

@@ -10,7 +10,7 @@ import 'package:flutter/services.dart';
 class DeviceInfoPlugin {
   /// Channel used to communicate to native code.
   static const MethodChannel channel =
-      const MethodChannel('plugins.flutter.io/device_info');
+      MethodChannel('plugins.flutter.io/device_info');
 
   DeviceInfoPlugin();