enable avoid_equals_and_hash_code_on_mutable_classes (#52507)

analysis_options.yaml

@@ -59,7 +59,7 @@ linter:
     - avoid_classes_with_only_static_members
     # - avoid_double_and_int_checks # only useful when targeting JS runtime
     - avoid_empty_else
-    # - avoid_equals_and_hash_code_on_mutable_classes # not yet tested
+    - avoid_equals_and_hash_code_on_mutable_classes
     - avoid_field_initializers_in_const_classes
     - avoid_function_literals_in_foreach_calls
     # - avoid_implementing_value_types # not yet tested

dev/bots/test/analyze_test.dart

@@ -95,7 +95,7 @@ void main() {
   test('analyze.dart - verifyNoBinaries - positive', () async {
     final String result = await capture(() => verifyNoBinaries(
       testRootPath,
-      grandfatheredBinaries: <Hash256>{Hash256(0x39A050CD69434936, 0, 0, 0)},
+      grandfatheredBinaries: <Hash256>{const Hash256(0x39A050CD69434936, 0, 0, 0)},
     ), exitCode: Platform.isWindows ? 0 : 1);
     if (!Platform.isWindows) {
       // The output starts with the call to git ls-files, the details of which
@@ -117,8 +117,8 @@ void main() {
     await capture(() => verifyNoBinaries(
       testRootPath,
       grandfatheredBinaries: <Hash256>{
-        Hash256(0xA8100AE6AA1940D0, 0xB663BB31CD466142, 0xEBBDBD5187131B92, 0xD93818987832EB89), // sha256("\xff")
-        Hash256(0x155644D3F13D98BF, 0, 0, 0),
+        const Hash256(0xA8100AE6AA1940D0, 0xB663BB31CD466142, 0xEBBDBD5187131B92, 0xD93818987832EB89), // sha256("\xff")
+        const Hash256(0x155644D3F13D98BF, 0, 0, 0),
       },
     ), exitCode: 0);
   });

dev/devicelab/test/adb_test.dart

@@ -7,6 +7,7 @@ import 'dart:async';
 import 'package:collection/collection.dart' show ListEquality, MapEquality;
 
 import 'package:flutter_devicelab/framework/adb.dart';
+import 'package:meta/meta.dart';
 
 import 'common.dart';
 
@@ -124,8 +125,9 @@ CommandArgs cmd({
 
 typedef ExitErrorFactory = dynamic Function();
 
+@immutable
 class CommandArgs {
-  CommandArgs({ this.command, this.arguments, this.environment });
+  const CommandArgs({ this.command, this.arguments, this.environment });
 
   final String command;
   final List<String> arguments;

dev/integration_tests/flutter_gallery/lib/demo/animation/sections.dart

@@ -26,6 +26,7 @@ class SectionDetail {
   final String imageAssetPackage;
 }
 
+@immutable
 class Section {
   const Section({
     this.title,

dev/integration_tests/flutter_gallery/lib/gallery/demo.dart

@@ -12,8 +12,9 @@ import 'demos.dart';
 import 'example_code_parser.dart';
 import 'syntax_highlighter.dart';
 
+@immutable
 class ComponentDemoTabData {
-  ComponentDemoTabData({
+  const ComponentDemoTabData({
     this.demoWidget,
     this.exampleCodeTag,
     this.description,

dev/integration_tests/flutter_gallery/lib/gallery/demos.dart

@@ -7,6 +7,7 @@ import 'package:flutter/material.dart';
 import '../demo/all.dart';
 import 'icons.dart';
 
+@immutable
 class GalleryDemoCategory {
   const GalleryDemoCategory._({
     @required this.name,

dev/integration_tests/flutter_gallery/lib/gallery/options.dart

@@ -7,8 +7,9 @@ import 'package:flutter/material.dart';
 import 'about.dart';
 import 'scales.dart';
 
+@immutable
 class GalleryOptions {
-  GalleryOptions({
+  const GalleryOptions({
     this.themeMode,
     this.textScaleFactor,
     this.visualDensity,

dev/integration_tests/flutter_gallery/lib/gallery/scales.dart

@@ -4,6 +4,7 @@
 
 import 'package:flutter/material.dart';
 
+@immutable
 class GalleryTextScaleValue {
   const GalleryTextScaleValue(this.scale, this.label);
 
@@ -37,6 +38,7 @@ const List<GalleryTextScaleValue> kAllGalleryTextScaleValues = <GalleryTextScale
   GalleryTextScaleValue(2.0, 'Huge'),
 ];
 
+@immutable
 class GalleryVisualDensityValue {
   const GalleryVisualDensityValue(this.visualDensity, this.label);
 

dev/tools/localization/localizations_utils.dart

@@ -18,8 +18,9 @@ int sortFilesByPath (FileSystemEntity a, FileSystemEntity b) {
 }
 
 /// Simple data class to hold parsed locale. Does not promise validity of any data.
+@immutable
 class LocaleInfo implements Comparable<LocaleInfo> {
-  LocaleInfo({
+  const LocaleInfo({
     this.languageCode,
     this.scriptCode,
     this.countryCode,

dev/tools/vitool/lib/vitool.dart

@@ -260,6 +260,7 @@ List<Point<double>> parsePoints(String points) {
 }
 
 /// Data for a single animation frame.
+@immutable
 class FrameData {
   const FrameData(this.size, this.paths);
 
@@ -285,6 +286,7 @@ class FrameData {
 }
 
 /// Represents an SVG path element.
+@immutable
 class SvgPath {
   const SvgPath(this.id, this.commands, {this.opacity = 1.0});
 
@@ -348,6 +350,7 @@ class SvgPath {
 ///   * "Z" => SvgPathCommand('Z', [])
 ///   * "C 1.0, 1.0 2.0, 2.0 3.0, 3.0" SvgPathCommand('C', [Point(1.0, 1.0),
 ///      Point(2.0, 2.0), Point(3.0, 3.0)])
+@immutable
 class SvgPathCommand {
   const SvgPathCommand(this.type, this.points);
 

packages/flutter/lib/src/cupertino/nav_bar.dart

@@ -52,6 +52,7 @@ const Border _kDefaultNavBarBorder = Border(
 // all transition between each other (per Navigator) via Hero transitions.
 const _HeroTag _defaultHeroTag = _HeroTag(null);
 
+@immutable
 class _HeroTag {
   const _HeroTag(this.navigator);
 

packages/flutter/lib/src/gestures/velocity_tracker.dart

@@ -11,6 +11,7 @@ import 'lsq_solver.dart';
 export 'dart:ui' show Offset;
 
 /// A velocity in two dimensions.
+@immutable
 class Velocity {
   /// Creates a velocity.
   ///

packages/flutter/lib/src/material/app_bar_theme.dart

@@ -27,6 +27,7 @@ import 'theme.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class AppBarTheme with Diagnosticable {
   /// Creates a theme that can be used for [ThemeData.AppBarTheme].
   const AppBarTheme({

packages/flutter/lib/src/material/banner_theme.dart

@@ -23,6 +23,7 @@ import 'theme.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class MaterialBannerThemeData with Diagnosticable {
 
   /// Creates a theme that can be used for [MaterialBannerTheme] or

packages/flutter/lib/src/material/bottom_app_bar_theme.dart

@@ -25,6 +25,7 @@ import 'theme.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class BottomAppBarTheme with Diagnosticable {
   /// Creates a theme that can be used for [ThemeData.BottomAppBarTheme].
   const BottomAppBarTheme({

packages/flutter/lib/src/material/bottom_sheet_theme.dart

@@ -24,6 +24,7 @@ import 'package:flutter/rendering.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class BottomSheetThemeData with Diagnosticable {
   /// Creates a theme that can be used for [ThemeData.bottomSheetTheme].
   const BottomSheetThemeData({

packages/flutter/lib/src/material/button_bar_theme.dart

@@ -24,6 +24,7 @@ import 'theme.dart';
 ///    its subtree.
 ///  * [ButtonBar], which uses this to configure itself and its children
 ///    button widgets.
+@immutable
 class ButtonBarThemeData with Diagnosticable {
   /// Constructs the set of properties used to configure [ButtonBar] widgets.
   ///

packages/flutter/lib/src/material/button_theme.dart

@@ -248,6 +248,7 @@ class ButtonTheme extends InheritedTheme {
 /// A button theme can be specified as part of the overall Material theme
 /// using [ThemeData.buttonTheme]. The Material theme's button theme data
 /// can be overridden with [ButtonTheme].
+@immutable
 class ButtonThemeData with Diagnosticable {
   /// Create a button theme object that can be used with [ButtonTheme]
   /// or [ThemeData].

packages/flutter/lib/src/material/card_theme.dart

@@ -26,6 +26,7 @@ import 'theme.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class CardTheme with Diagnosticable {
 
   /// Creates a theme that can be used for [ThemeData.cardTheme].

packages/flutter/lib/src/material/chip.dart

@@ -2157,6 +2157,7 @@ class _RenderChipElement extends RenderObjectElement {
   }
 }
 
+@immutable
 class _ChipRenderTheme {
   const _ChipRenderTheme({
     @required this.avatar,

packages/flutter/lib/src/material/chip_theme.dart

@@ -168,6 +168,7 @@ class ChipTheme extends InheritedTheme {
 ///  * [Theme] widget, which performs a similar function to [ChipTheme],
 ///    but for overall themes.
 ///  * [ThemeData], which has a default [ChipThemeData].
+@immutable
 class ChipThemeData with Diagnosticable {
   /// Create a [ChipThemeData] given a set of exact values. All the values
   /// must be specified except for [shadowColor], [selectedShadowColor],

packages/flutter/lib/src/material/dialog_theme.dart

@@ -27,6 +27,7 @@ import 'theme.dart';
 ///  * [Dialog], a material dialog that can be customized using this [DialogTheme].
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class DialogTheme with Diagnosticable {
   /// Creates a dialog theme that can be used for [ThemeData.dialogTheme].
   const DialogTheme({

packages/flutter/lib/src/material/divider_theme.dart

@@ -26,6 +26,7 @@ import 'theme.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class DividerThemeData with Diagnosticable {
 
   /// Creates a theme that can be used for [DividerTheme] or

packages/flutter/lib/src/material/dropdown.dart

@@ -368,6 +368,7 @@ class _DropdownMenuRouteLayout<T> extends SingleChildLayoutDelegate {
 // We box the return value so that the return value can be null. Otherwise,
 // canceling the route (which returns null) would get confused with actually
 // returning a real null value.
+@immutable
 class _DropdownRouteResult<T> {
   const _DropdownRouteResult(this.result);
 

packages/flutter/lib/src/material/floating_action_button_theme.dart

@@ -26,6 +26,7 @@ import 'package:flutter/rendering.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class FloatingActionButtonThemeData with Diagnosticable {
   /// Creates a theme that can be used for
   /// [ThemeData.floatingActionButtonTheme].

packages/flutter/lib/src/material/input_decorator.dart

@@ -40,6 +40,7 @@ class _InputBorderGap extends ChangeNotifier {
   }
 
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes, this class is not used in collection
   bool operator ==(Object other) {
     if (identical(this, other))
       return true;
@@ -51,6 +52,7 @@ class _InputBorderGap extends ChangeNotifier {
   }
 
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes, this class is not used in collection
   int get hashCode => hashValues(start, extent);
 }
 
@@ -489,6 +491,7 @@ enum _DecorationSlot {
 }
 
 // An analog of InputDecoration for the _Decorator widget.
+@immutable
 class _Decoration {
   const _Decoration({
     @required this.contentPadding,

packages/flutter/lib/src/material/navigation_rail_theme.dart

@@ -33,6 +33,7 @@ import 'theme_data.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class NavigationRailThemeData with Diagnosticable {
   /// Creates a theme that can be used for [ThemeData.navigationRailTheme].
   const NavigationRailThemeData({

packages/flutter/lib/src/material/popup_menu_theme.dart

@@ -29,6 +29,7 @@ import 'theme.dart';
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class PopupMenuThemeData with Diagnosticable {
   /// Creates the set of properties used to configure [PopupMenuTheme].
   const PopupMenuThemeData({

packages/flutter/lib/src/material/slider_theme.dart

@@ -305,6 +305,7 @@ enum Thumb {
 /// {@macro flutter.material.slider.seeAlso.rangeSliderValueIndicatorShape}
 /// {@macro flutter.material.slider.seeAlso.rangeSliderTrackShape}
 /// {@macro flutter.material.slider.seeAlso.rangeSliderTickMarkShape}
+@immutable
 class SliderThemeData with Diagnosticable {
   /// Create a [SliderThemeData] given a set of exact values. All the values
   /// must be specified.
@@ -2866,6 +2867,7 @@ typedef RangeThumbSelector = Thumb Function(
 /// This object is passed into [RangeSlider.values] to set its values, and it
 /// is emitted in [RangeSlider.onChange], [RangeSlider.onChangeStart], and
 /// [RangeSlider.onChangeEnd] when the values change.
+@immutable
 class RangeValues {
   /// Creates pair of start and end values.
   const RangeValues(this.start, this.end);
@@ -2905,6 +2907,7 @@ class RangeValues {
 ///
 /// Used in combination with [RangeSlider.showValueIndicator] to display
 /// labels above the thumbs.
+@immutable
 class RangeLabels {
   /// Creates pair of start and end labels.
   const RangeLabels(this.start, this.end);

packages/flutter/lib/src/material/snack_bar_theme.dart

@@ -46,6 +46,7 @@ enum SnackBarBehavior {
 ///
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class SnackBarThemeData with Diagnosticable {
 
   /// Creates a theme that can be used for [ThemeData.snackBarTheme].

packages/flutter/lib/src/material/tab_bar_theme.dart

@@ -23,6 +23,7 @@ import 'theme.dart';
 ///  * [TabBar], a widget that displays a horizontal row of tabs.
 ///  * [ThemeData], which describes the overall theme information for the
 ///    application.
+@immutable
 class TabBarTheme with Diagnosticable {
   /// Creates a tab bar theme that can be used with [ThemeData.tabBarTheme].
   const TabBarTheme({

packages/flutter/lib/src/material/theme_data.dart

@@ -1636,8 +1636,9 @@ class MaterialBasedCupertinoThemeData extends CupertinoThemeData {
   }
 }
 
+@immutable
 class _IdentityThemeDataCacheKey {
-  _IdentityThemeDataCacheKey(this.baseTheme, this.localTextGeometry);
+  const _IdentityThemeDataCacheKey(this.baseTheme, this.localTextGeometry);
 
   final ThemeData baseTheme;
   final TextTheme localTextGeometry;
@@ -1713,6 +1714,7 @@ class _FifoCache<K, V> {
 ///  * [ThemeData.visualDensity], where this property is used to specify the base
 ///    horizontal density of Material components.
 ///  * [Material design guidance on density](https://material.io/design/layout/applying-density.html).
+@immutable
 class VisualDensity with Diagnosticable {
   /// A const constructor for [VisualDensity].
   ///

packages/flutter/lib/src/material/toggle_buttons_theme.dart

@@ -24,6 +24,7 @@ import 'theme.dart';
 ///
 ///  * [ToggleButtonsTheme], which describes the actual configuration of a
 ///    toggle buttons theme.
+@immutable
 class ToggleButtonsThemeData with Diagnosticable {
   /// Creates the set of color and border properties used to configure
   /// [ToggleButtons].

packages/flutter/lib/src/material/tooltip_theme.dart

@@ -23,6 +23,7 @@ import 'theme.dart';
 ///    subtree.
 ///  * [TooltipThemeData], which describes the actual configuration of a
 ///    tooltip theme.
+@immutable
 class TooltipThemeData with Diagnosticable {
   /// Creates the set of properties used to configure [Tooltip]s.
   const TooltipThemeData({

packages/flutter/lib/src/painting/_network_image_io.dart

@@ -15,6 +15,7 @@ import 'image_provider.dart' as image_provider;
 import 'image_stream.dart';
 
 /// The dart:io implementation of [image_provider.NetworkImage].
+@immutable
 class NetworkImage extends image_provider.ImageProvider<image_provider.NetworkImage> implements image_provider.NetworkImage {
   /// Creates an object that fetches the image at the given URL.
   ///

packages/flutter/lib/src/painting/_network_image_web.dart

@@ -13,6 +13,7 @@ import 'image_stream.dart';
 /// The dart:html implementation of [image_provider.NetworkImage].
 ///
 /// NetworkImage on the web does not support decoding to a specified size.
+@immutable
 class NetworkImage
     extends image_provider.ImageProvider<image_provider.NetworkImage>
     implements image_provider.NetworkImage {

packages/flutter/lib/src/painting/colors.dart

@@ -425,6 +425,7 @@ class HSLColor {
 ///    primary and accent color swatches.
 ///  * [material.Colors], which defines all of the standard material design
 ///    colors.
+@immutable
 class ColorSwatch<T> extends Color {
   /// Creates a color that has a small table of related colors called a "swatch".
   ///

packages/flutter/lib/src/painting/image_cache.dart

@@ -530,6 +530,7 @@ class ImageCache {
 ///
 /// To obtain an [ImageCacheStatus], use [ImageCache.statusForKey] or
 /// [ImageProvider.obtainCacheStatus].
+@immutable
 class ImageCacheStatus {
   const ImageCacheStatus._({
     this.pending = false,

packages/flutter/lib/src/painting/image_provider.dart

@@ -674,6 +674,7 @@ abstract class AssetBundleImageProvider extends ImageProvider<AssetBundleImageKe
   }
 }
 
+@immutable
 class _SizeAwareCacheKey {
   const _SizeAwareCacheKey(this.providerCacheKey, this.width, this.height);
 
@@ -818,6 +819,7 @@ abstract class NetworkImage extends ImageProvider<NetworkImage> {
 /// See also:
 ///
 ///  * [Image.file] for a shorthand of an [Image] widget backed by [FileImage].
+@immutable
 class FileImage extends ImageProvider<FileImage> {
   /// Creates an object that decodes a [File] as an image.
   ///
@@ -890,6 +892,7 @@ class FileImage extends ImageProvider<FileImage> {
 /// See also:
 ///
 ///  * [Image.memory] for a shorthand of an [Image] widget backed by [MemoryImage].
+@immutable
 class MemoryImage extends ImageProvider<MemoryImage> {
   /// Creates an object that decodes a [Uint8List] buffer as an image.
   ///
@@ -1008,6 +1011,7 @@ class MemoryImage extends ImageProvider<MemoryImage> {
 ///
 ///  * [Image.asset] for a shorthand of an [Image] widget backed by
 ///    [ExactAssetImage] when using a scale.
+@immutable
 class ExactAssetImage extends AssetBundleImageProvider {
   /// Creates an object that fetches the given image from an asset bundle.
   ///

packages/flutter/lib/src/painting/image_resolution.dart

@@ -120,6 +120,7 @@ const String _kAssetManifestFileName = 'AssetManifest.json';
 ///
 ///  * [Image.asset] for a shorthand of an [Image] widget backed by [AssetImage]
 ///    when used without a scale.
+@immutable
 class AssetImage extends AssetBundleImageProvider {
   /// Creates an object that fetches an image from an asset bundle.
   ///

packages/flutter/lib/src/services/keyboard_key.dart

@@ -121,6 +121,7 @@ abstract class KeyboardKey with Diagnosticable {
 ///    to keyboard events.
 ///  * [RawKeyboardListener], a widget used to listen to and supply handlers for
 ///    keyboard events.
+@immutable
 class LogicalKeyboardKey extends KeyboardKey {
   /// Creates a LogicalKeyboardKey object with an optional key label and debug
   /// name.
@@ -2043,6 +2044,7 @@ class LogicalKeyboardKey extends KeyboardKey {
 ///    to keyboard events.
 ///  * [RawKeyboardListener], a widget used to listen to and supply handlers for
 ///    keyboard events.
+@immutable
 class PhysicalKeyboardKey extends KeyboardKey {
   /// Creates a PhysicalKeyboardKey object with an optional debug name.
   ///

packages/flutter/lib/src/services/raw_keyboard.dart

@@ -623,6 +623,7 @@ class RawKeyboard {
   void clearKeysPressed() => _keysPressed.clear();
 }
 
+@immutable
 class _ModifierSidePair extends Object {
   const _ModifierSidePair(this.modifier, this.side);
 

packages/flutter/lib/src/services/system_chrome.dart

@@ -83,6 +83,7 @@ enum SystemUiOverlay {
 /// Specifies a preference for the style of the system overlays.
 ///
 /// Used by [SystemChrome.setSystemUIOverlayStyle].
+@immutable
 class SystemUiOverlayStyle {
   /// Creates a new [SystemUiOverlayStyle].
   const SystemUiOverlayStyle({

packages/flutter/lib/src/services/text_input.dart

@@ -82,6 +82,7 @@ enum SmartQuotesType {
 /// This class stays as close to [Enum] interface as possible, and allows
 /// for additional flags for some input types. For example, numeric input
 /// can specify whether it supports decimal numbers and/or signed numbers.
+@immutable
 class TextInputType {
   const TextInputType._(this.index)
     : signed = null,

packages/flutter/lib/src/widgets/framework.dart

@@ -2887,7 +2887,9 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
 
   // Custom implementation of `operator ==` optimized for the ".of" pattern
   // used with `InheritedWidgets`.
+  @nonVirtual
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes
   bool operator ==(Object other) => identical(this, other);
 
   // Custom implementation of hash code optimized for the ".of" pattern used
@@ -2904,7 +2906,9 @@ abstract class Element extends DiagnosticableTree implements BuildContext {
   //
   //  * https://dart.dev/articles/dart-vm/numeric-computation, which
   //    explains how numbers are represented in Dart.
+  @nonVirtual
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes
   int get hashCode => _cachedHash;
   final int _cachedHash = _nextHashCode = (_nextHashCode + 1) % 0xffffff;
   static int _nextHashCode = 1;

packages/flutter/lib/src/widgets/icon_theme_data.dart

@@ -18,6 +18,7 @@ import 'framework.dart' show BuildContext;
 /// To obtain the current icon theme, use [IconTheme.of]. To convert an icon
 /// theme to a version with all the fields filled in, use [new
 /// IconThemeData.fallback].
+@immutable
 class IconThemeData with Diagnosticable {
   /// Creates an icon theme data.
   ///

packages/flutter/lib/src/widgets/page_storage.dart

@@ -38,8 +38,9 @@ class PageStorageKey<T> extends ValueKey<T> {
   const PageStorageKey(T value) : super(value);
 }
 
+@immutable
 class _StorageEntryIdentifier {
-  _StorageEntryIdentifier(this.keys)
+  const _StorageEntryIdentifier(this.keys)
     : assert(keys != null);
 
   final List<PageStorageKey<dynamic>> keys;

packages/flutter/lib/src/widgets/shortcuts.dart

@@ -82,6 +82,7 @@ class KeySet<T extends KeyboardKey> {
   final HashSet<T> _keys;
 
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes, to remove in NNBD with a late final hashcode
   bool operator ==(Object other) {
     if (other.runtimeType != runtimeType) {
       return false;
@@ -99,6 +100,7 @@ class KeySet<T extends KeyboardKey> {
   int _hashCode;
 
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes, to remove in NNBD with a late final hashcode
   int get hashCode {
     // Return cached hash code if available.
     if (_hashCode != null) {

packages/flutter/lib/src/widgets/widget_inspector.dart

@@ -2426,6 +2426,7 @@ class _RenderInspectorOverlay extends RenderBox {
   }
 }
 
+@immutable
 class _TransformedRect {
   _TransformedRect(RenderObject object)
     : rect = object.semanticBounds,
@@ -2451,8 +2452,9 @@ class _TransformedRect {
 ///
 /// The equality operator can be used to determine whether the overlay needs to
 /// be rendered again.
+@immutable
 class _InspectorOverlayRenderState {
-  _InspectorOverlayRenderState({
+  const _InspectorOverlayRenderState({
     @required this.overlayRect,
     @required this.selected,
     @required this.candidates,

packages/flutter/test/painting/image_provider_test.dart

@@ -553,7 +553,7 @@ Future<Size> _resolveAndGetSize(ImageProvider imageProvider,
 // This version of MemoryImage guarantees obtainKey returns a future that has not been
 // completed synchronously.
 class AsyncKeyMemoryImage extends MemoryImage {
-  AsyncKeyMemoryImage(Uint8List bytes) : super(bytes);
+  const AsyncKeyMemoryImage(Uint8List bytes) : super(bytes);
 
   @override
   Future<MemoryImage> obtainKey(ImageConfiguration configuration) {

packages/flutter/test/services/fake_platform_views.dart

@@ -157,7 +157,7 @@ class FakeAndroidPlatformViewsController {
     if (resizeCompleter != null) {
       await resizeCompleter.future;
     }
-    _views[id].size = Size(width, height);
+    _views[id] = _views[id].copyWith(size: Size(width, height));
 
     return Future<dynamic>.sync(() => null);
   }
@@ -195,7 +195,7 @@ class FakeAndroidPlatformViewsController {
         message: 'Trying to resize a platform view with unknown id: $id',
       );
 
-    _views[id].layoutDirection = layoutDirection;
+    _views[id] = _views[id].copyWith(layoutDirection: layoutDirection);
 
     return Future<dynamic>.sync(() => null);
   }
@@ -377,14 +377,23 @@ class FakeHtmlPlatformViewsController {
   }
 }
 
+@immutable
 class FakeAndroidPlatformView {
-  FakeAndroidPlatformView(this.id, this.type, this.size, this.layoutDirection, [this.creationParams]);
+  const FakeAndroidPlatformView(this.id, this.type, this.size, this.layoutDirection, [this.creationParams]);
 
   final int id;
   final String type;
   final Uint8List creationParams;
-  Size size;
-  int layoutDirection;
+  final Size size;
+  final int layoutDirection;
+
+  FakeAndroidPlatformView copyWith({Size size, int layoutDirection}) => FakeAndroidPlatformView(
+    id,
+    type,
+    size ?? this.size,
+    layoutDirection ?? this.layoutDirection,
+    creationParams,
+  );
 
   @override
   bool operator ==(Object other) {
@@ -393,12 +402,13 @@ class FakeAndroidPlatformView {
     return other is FakeAndroidPlatformView
         && other.id == id
         && other.type == type
-        && other.creationParams == creationParams
-        && other.size == size;
+        && listEquals<int>(other.creationParams, creationParams)
+        && other.size == size
+        && other.layoutDirection == layoutDirection;
   }
 
   @override
-  int get hashCode => hashValues(id, type, size, layoutDirection);
+  int get hashCode => hashValues(id, type, hashList(creationParams), size, layoutDirection);
 
   @override
   String toString() {
@@ -406,6 +416,7 @@ class FakeAndroidPlatformView {
   }
 }
 
+@immutable
 class FakeAndroidMotionEvent {
   const FakeAndroidMotionEvent(this.action, this.pointerIds, this.pointers);
 
@@ -431,8 +442,9 @@ class FakeAndroidMotionEvent {
   }
 }
 
+@immutable
 class FakeUiKitView {
-  FakeUiKitView(this.id, this.type, [this.creationParams]);
+  const FakeUiKitView(this.id, this.type, [this.creationParams]);
 
   final int id;
   final String type;
@@ -457,8 +469,9 @@ class FakeUiKitView {
   }
 }
 
+@immutable
 class FakeHtmlPlatformView {
-  FakeHtmlPlatformView(this.id, this.type);
+  const FakeHtmlPlatformView(this.id, this.type);
 
   final int id;
   final String type;

packages/flutter/test/services/platform_views_test.dart

@@ -40,8 +40,8 @@ void main() {
       expect(
           viewsController.views,
           unorderedEquals(<FakeAndroidPlatformView>[
-            FakeAndroidPlatformView(0, 'webview', const Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
-            FakeAndroidPlatformView(1, 'webview', const Size(200.0, 300.0), AndroidViewController.kAndroidLayoutDirectionRtl),
+            const FakeAndroidPlatformView(0, 'webview', Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
+            const FakeAndroidPlatformView(1, 'webview', Size(200.0, 300.0), AndroidViewController.kAndroidLayoutDirectionRtl),
           ]));
     });
 
@@ -70,7 +70,7 @@ void main() {
       expect(
           viewsController.views,
           unorderedEquals(<FakeAndroidPlatformView>[
-            FakeAndroidPlatformView(0, 'webview', const Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
+            const FakeAndroidPlatformView(0, 'webview', Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
           ]));
     });
 
@@ -96,8 +96,8 @@ void main() {
       expect(
           viewsController.views,
           unorderedEquals(<FakeAndroidPlatformView>[
-            FakeAndroidPlatformView(0, 'webview', const Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
-            FakeAndroidPlatformView(1, 'webview', const Size(500.0, 500.0), AndroidViewController.kAndroidLayoutDirectionLtr),
+            const FakeAndroidPlatformView(0, 'webview', Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
+            const FakeAndroidPlatformView(1, 'webview', Size(500.0, 500.0), AndroidViewController.kAndroidLayoutDirectionLtr),
           ]));
     });
 
@@ -137,7 +137,7 @@ void main() {
       expect(
           viewsController.views,
           unorderedEquals(<FakeAndroidPlatformView>[
-            FakeAndroidPlatformView(0, 'webview', const Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
+            const FakeAndroidPlatformView(0, 'webview', Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr),
           ]));
     });
 
@@ -150,7 +150,7 @@ void main() {
       expect(
           viewsController.views,
           unorderedEquals(<FakeAndroidPlatformView>[
-            FakeAndroidPlatformView(0, 'webview', const Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionRtl),
+            const FakeAndroidPlatformView(0, 'webview', Size(100.0, 100.0), AndroidViewController.kAndroidLayoutDirectionRtl),
           ]));
     });
   });
@@ -183,8 +183,8 @@ void main() {
       expect(
         viewsController.views,
         unorderedEquals(<FakeUiKitView>[
-          FakeUiKitView(0, 'webview'),
-          FakeUiKitView(1, 'webview'),
+          const FakeUiKitView(0, 'webview'),
+          const FakeUiKitView(1, 'webview'),
         ]),
       );
     });
@@ -214,7 +214,7 @@ void main() {
       expect(
           viewsController.views,
           unorderedEquals(<FakeUiKitView>[
-            FakeUiKitView(0, 'webview'),
+            const FakeUiKitView(0, 'webview'),
           ]));
     });
 

packages/flutter/test/widgets/image_resolution_test.dart

@@ -103,7 +103,7 @@ class FakeImageStreamCompleter extends ImageStreamCompleter {
 }
 
 class TestAssetImage extends AssetImage {
-  TestAssetImage(String name) : super(name);
+  const TestAssetImage(String name) : super(name);
 
   @override
   ImageStreamCompleter load(AssetBundleImageKey key, DecoderCallback decode) {

packages/flutter/test/widgets/image_test.dart

@@ -1622,6 +1622,7 @@ void main() {
   });
 }
 
+@immutable
 class ConfigurationAwareKey {
   const ConfigurationAwareKey(this.provider, this.configuration)
     : assert(provider != null),

packages/flutter/test/widgets/key_test.dart

@@ -9,6 +9,7 @@ class TestValueKey<T> extends ValueKey<T> {
   const TestValueKey(T value) : super(value);
 }
 
+@immutable
 class NotEquals {
   const NotEquals();
   @override

packages/flutter/test/widgets/shortcuts_test.dart

@@ -68,6 +68,7 @@ void main() {
         LogicalKeyboardKey.keyC,
         LogicalKeyboardKey.keyD,
       );
+      // ignore: prefer_const_literals_to_create_immutables, https://github.com/dart-lang/linter/issues/2026
       final LogicalKeySet setFromSet = LogicalKeySet.fromSet(<LogicalKeyboardKey>{
         LogicalKeyboardKey.keyA,
         LogicalKeyboardKey.keyB,
@@ -123,6 +124,7 @@ void main() {
         LogicalKeyboardKey.keyB,
         LogicalKeyboardKey.keyA,
       );
+      // ignore: prefer_const_literals_to_create_immutables, https://github.com/dart-lang/linter/issues/2026
       final LogicalKeySet set4 = LogicalKeySet.fromSet(<LogicalKeyboardKey>{
         LogicalKeyboardKey.keyD,
         LogicalKeyboardKey.keyC,
@@ -138,6 +140,7 @@ void main() {
       expect(map.containsKey(LogicalKeySet(LogicalKeyboardKey.keyA)), isTrue);
       expect(
           set2,
+          // ignore: prefer_const_literals_to_create_immutables, https://github.com/dart-lang/linter/issues/2026
           equals(LogicalKeySet.fromSet(<LogicalKeyboardKey>{
             LogicalKeyboardKey.keyA,
             LogicalKeyboardKey.keyB,

packages/flutter_driver/lib/src/driver/driver.dart

@@ -748,6 +748,7 @@ class CommonFinders {
 }
 
 /// An immutable 2D floating-point offset used by Flutter Driver.
+@immutable
 class DriverOffset {
   /// Creates an offset.
   const DriverOffset(this.dx, this.dy);

packages/flutter_test/test/matchers_test.dart

@@ -240,27 +240,27 @@ void main() {
   test('isSameColorAs', () {
     expect(
       const Color(0x87654321),
-      isSameColorAs(_CustomColor(0x87654321)),
+      isSameColorAs(const _CustomColor(0x87654321)),
     );
 
     expect(
-      _CustomColor(0x87654321),
+      const _CustomColor(0x87654321),
       isSameColorAs(const Color(0x87654321)),
     );
 
     expect(
       const Color(0x12345678),
-      isNot(isSameColorAs(_CustomColor(0x87654321))),
+      isNot(isSameColorAs(const _CustomColor(0x87654321))),
     );
 
     expect(
-      _CustomColor(0x87654321),
+      const _CustomColor(0x87654321),
       isNot(isSameColorAs(const Color(0x12345678))),
     );
 
     expect(
-      _CustomColor(0xFF123456),
-      isSameColorAs(_CustomColor(0xFF123456)..isEqual = false),
+      const _CustomColor(0xFF123456),
+      isSameColorAs(const _CustomColor(0xFF123456, isEqual: false)),
     );
   });
 
@@ -704,9 +704,10 @@ class _FakeSemanticsNode extends SemanticsNode {
   SemanticsData getSemanticsData() => data;
 }
 
+@immutable
 class _CustomColor extends Color {
-  _CustomColor(int value) : super(value);
-  bool isEqual;
+  const _CustomColor(int value, {this.isEqual}) : super(value);
+  final bool isEqual;
 
   @override
   bool operator ==(Object other) => isEqual ?? super == other;

packages/flutter_tools/lib/src/asset.dart

@@ -273,8 +273,9 @@ class _ManifestAssetBundle implements AssetBundle {
   List<File> additionalDependencies = <File>[];
 }
 
+@immutable
 class _Asset {
-  _Asset({ this.baseDir, this.relativeUri, this.entryUri });
+  const _Asset({ this.baseDir, this.relativeUri, this.entryUri });
 
   final String baseDir;
 

packages/flutter_tools/lib/src/base/fingerprint.dart

@@ -98,39 +98,49 @@ class Fingerprinter {
 /// properties.
 ///
 /// See [Fingerprinter].
+@immutable
 class Fingerprint {
-  Fingerprint.fromBuildInputs(Map<String, String> properties, Iterable<String> inputPaths) {
+  const Fingerprint._({
+    Map<String, String> checksums,
+    Map<String, String> properties,
+  })  : _checksums = checksums,
+        _properties = properties;
+
+  factory Fingerprint.fromBuildInputs(Map<String, String> properties, Iterable<String> inputPaths) {
     final Iterable<File> files = inputPaths.map<File>(globals.fs.file);
     final Iterable<File> missingInputs = files.where((File file) => !file.existsSync());
     if (missingInputs.isNotEmpty) {
       throw Exception('Missing input files:\n' + missingInputs.join('\n'));
     }
-
-    _checksums = <String, String>{};
-    for (final File file in files) {
-      final List<int> bytes = file.readAsBytesSync();
-      _checksums[file.path] = md5.convert(bytes).toString();
-    }
-    _properties = <String, String>{...properties};
+    return Fingerprint._(
+      // ignore: prefer_const_literals_to_create_immutables, https://github.com/dart-lang/linter/issues/2025
+      checksums: <String, String>{
+        for (final File file in files)
+          file.path: md5.convert(file.readAsBytesSync()).toString(),
+      },
+      properties: <String, String>{...properties},
+    );
   }
 
   /// Creates a Fingerprint from serialized JSON.
   ///
   /// Throws [Exception], if there is a version mismatch between the
   /// serializing framework and this framework.
-  Fingerprint.fromJson(String jsonData) {
+  factory Fingerprint.fromJson(String jsonData) {
     final Map<String, dynamic> content = castStringKeyedMap(json.decode(jsonData));
 
     final String version = content['version'] as String;
     if (version != globals.flutterVersion.frameworkRevision) {
       throw Exception('Incompatible fingerprint version: $version');
     }
-    _checksums = castStringKeyedMap(content['files'])?.cast<String,String>() ?? <String, String>{};
-    _properties = castStringKeyedMap(content['properties'])?.cast<String,String>() ?? <String, String>{};
+    return Fingerprint._(
+      checksums: castStringKeyedMap(content['files'])?.cast<String,String>() ?? <String, String>{},
+      properties: castStringKeyedMap(content['properties'])?.cast<String,String>() ?? <String, String>{},
+    );
   }
 
-  Map<String, String> _checksums;
-  Map<String, String> _properties;
+  final Map<String, String> _checksums;
+  final Map<String, String> _properties;
 
   String toJson() => json.encode(<String, dynamic>{
     'version': globals.flutterVersion.frameworkRevision,

packages/flutter_tools/lib/src/base/version.dart

@@ -2,6 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+import 'package:meta/meta.dart';
+
+@immutable
 class Version implements Comparable<Version> {
   /// Creates a new [Version] object.
   factory Version(int major, int minor, int patch, {String text}) {

packages/flutter_tools/lib/src/device.dart

@@ -480,10 +480,14 @@ abstract class Device {
 
   Future<void> takeScreenshot(File outputFile) => Future<void>.error('unimplemented');
 
+  @nonVirtual
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes
   int get hashCode => id.hashCode;
 
+  @nonVirtual
   @override
+  // ignore: avoid_equals_and_hash_code_on_mutable_classes
   bool operator ==(Object other) {
     if (identical(this, other)) {
       return true;

packages/flutter_tools/lib/src/doctor.dart

@@ -481,14 +481,15 @@ class GroupedValidator extends DoctorValidator {
   }
 }
 
+@immutable
 class ValidationResult {
   /// [ValidationResult.type] should only equal [ValidationResult.installed]
   /// if no [messages] are hints or errors.
-  ValidationResult(this.type, this.messages, { this.statusInfo });
+  const ValidationResult(this.type, this.messages, { this.statusInfo });
 
   factory ValidationResult.crash(Object error, [StackTrace stackTrace]) {
     return ValidationResult(ValidationType.crash, <ValidationMessage>[
-      ValidationMessage.error(
+      const ValidationMessage.error(
           'Due to an error, the doctor check did not complete. '
           'If the error message below is not helpful, '
           'please let us know about this issue at https://github.com/flutter/flutter/issues.'),
@@ -555,10 +556,11 @@ class ValidationResult {
   }
 }
 
+@immutable
 class ValidationMessage {
-  ValidationMessage(this.message) : type = ValidationMessageType.information;
-  ValidationMessage.error(this.message) : type = ValidationMessageType.error;
-  ValidationMessage.hint(this.message) : type = ValidationMessageType.hint;
+  const ValidationMessage(this.message) : type = ValidationMessageType.information;
+  const ValidationMessage.error(this.message) : type = ValidationMessageType.error;
+  const ValidationMessage.hint(this.message) : type = ValidationMessageType.hint;
 
   final ValidationMessageType type;
   bool get isError => type == ValidationMessageType.error;
@@ -714,7 +716,7 @@ abstract class IntelliJValidator extends DoctorValidator {
     final List<ValidationMessage> messages = <ValidationMessage>[];
 
     if (pluginsPath == null) {
-      messages.add(ValidationMessage.error('Invalid IntelliJ version number.'));
+      messages.add(const ValidationMessage.error('Invalid IntelliJ version number.'));
     } else {
       messages.add(ValidationMessage(userMessages.intellijLocation(installPath)));
 

packages/flutter_tools/lib/src/emulator.dart

@@ -5,6 +5,8 @@
 import 'dart:async';
 import 'dart:math' as math;
 
+import 'package:meta/meta.dart';
+
 import 'android/android_emulator.dart';
 import 'android/android_sdk.dart';
 import 'base/context.dart';
@@ -214,8 +216,9 @@ abstract class EmulatorDiscovery {
   Future<List<Emulator>> get emulators;
 }
 
+@immutable
 abstract class Emulator {
-  Emulator(this.id, this.hasConfig);
+  const Emulator(this.id, this.hasConfig);
 
   final String id;
   final bool hasConfig;

packages/flutter_tools/lib/src/ios/ios_emulators.dart

@@ -22,7 +22,7 @@ class IOSEmulators extends EmulatorDiscovery {
 }
 
 class IOSEmulator extends Emulator {
-  IOSEmulator(String id) : super(id, true);
+  const IOSEmulator(String id) : super(id, true);
 
   @override
   String get name => 'iOS Simulator';

packages/flutter_tools/lib/src/linux/linux_doctor.dart

@@ -37,7 +37,7 @@ class LinuxDoctorValidator extends DoctorValidator {
     }
     if (clangResult == null || clangResult.exitCode != 0) {
       validationType = ValidationType.missing;
-      messages.add(ValidationMessage.error('clang++ is not installed'));
+      messages.add(const ValidationMessage.error('clang++ is not installed'));
     } else {
       final String firstLine = (clangResult.stdout as String).split('\n').first.trim();
       final String versionString = RegExp(r'[0-9]+\.[0-9]+\.[0-9]+').firstMatch(firstLine).group(0);
@@ -64,7 +64,7 @@ class LinuxDoctorValidator extends DoctorValidator {
     }
     if (makeResult == null || makeResult.exitCode != 0) {
       validationType = ValidationType.missing;
-      messages.add(ValidationMessage.error('make is not installed'));
+      messages.add(const ValidationMessage.error('make is not installed'));
     } else {
       final String firstLine = (makeResult.stdout as String).split('\n').first.trim();
       messages.add(ValidationMessage(firstLine));

packages/flutter_tools/lib/src/proxy_validator.dart

@@ -28,10 +28,10 @@ class ProxyValidator extends DoctorValidator {
     final List<ValidationMessage> messages = <ValidationMessage>[];
 
     if (_httpProxy.isNotEmpty) {
-      messages.add(ValidationMessage('HTTP_PROXY is set'));
+      messages.add(const ValidationMessage('HTTP_PROXY is set'));
 
       if (_noProxy.isEmpty) {
-        messages.add(ValidationMessage.hint('NO_PROXY is not set'));
+        messages.add(const ValidationMessage.hint('NO_PROXY is not set'));
       } else {
         messages.add(ValidationMessage('NO_PROXY is $_noProxy'));
         for (final String host in const <String>['127.0.0.1', 'localhost']) {

packages/flutter_tools/lib/src/vscode/vscode.dart

@@ -30,7 +30,7 @@ class VsCode {
 
     // If the extensions directory doesn't exist at all, the listSync()
     // below will fail, so just bail out early.
-    final ValidationMessage notInstalledMessage = ValidationMessage.error(
+    const ValidationMessage notInstalledMessage = ValidationMessage.error(
           'Flutter extension not installed; install from\n$extensionMarketplaceUrl');
     if (!globals.fs.isDirectorySync(extensionDirectory)) {
       _validationMessages.add(notInstalledMessage);

packages/flutter_tools/lib/src/web/web_validator.dart

@@ -36,7 +36,7 @@ class WebValidator extends DoctorValidator {
           ValidationMessage('$kChromeEnvironment = $chrome')
       else
         if (!canRunChrome)
-          ValidationMessage.hint('Cannot find Chrome. Try setting '
+          const ValidationMessage.hint('Cannot find Chrome. Try setting '
             '$kChromeEnvironment to a Chrome executable.')
         else
           ValidationMessage('Chrome at $chrome'),

packages/flutter_tools/test/commands.shard/hermetic/doctor_test.dart

@@ -801,11 +801,11 @@ class PassingValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage('A helpful message'),
       ValidationMessage('A second, somewhat longer helpful message'),
     ];
-    return ValidationResult(ValidationType.installed, messages, statusInfo: 'with statusInfo');
+    return const ValidationResult(ValidationType.installed, messages, statusInfo: 'with statusInfo');
   }
 }
 
@@ -814,12 +814,12 @@ class MissingValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage.error('A useful error message'),
       ValidationMessage('A message that is not an error'),
       ValidationMessage.hint('A hint message'),
     ];
-    return ValidationResult(ValidationType.missing, messages);
+    return const ValidationResult(ValidationType.missing, messages);
   }
 }
 
@@ -828,12 +828,12 @@ class NotAvailableValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage.error('A useful error message'),
       ValidationMessage('A message that is not an error'),
       ValidationMessage.hint('A hint message'),
     ];
-    return ValidationResult(ValidationType.notAvailable, messages);
+    return const ValidationResult(ValidationType.notAvailable, messages);
   }
 }
 
@@ -842,12 +842,12 @@ class PartialValidatorWithErrors extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage.error('An error message indicating partial installation'),
       ValidationMessage.hint('Maybe a hint will help the user'),
       ValidationMessage('An extra message with some verbose details'),
     ];
-    return ValidationResult(ValidationType.partial, messages);
+    return const ValidationResult(ValidationType.partial, messages);
   }
 }
 
@@ -856,11 +856,11 @@ class PartialValidatorWithHintsOnly extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage.hint('There is a hint here'),
       ValidationMessage('But there is no error'),
     ];
-    return ValidationResult(ValidationType.partial, messages);
+    return const ValidationResult(ValidationType.partial, messages);
   }
 }
 
@@ -1006,10 +1006,10 @@ class PassingGroupedValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage('A helpful message'),
     ];
-    return ValidationResult(ValidationType.installed, messages);
+    return const ValidationResult(ValidationType.installed, messages);
   }
 }
 
@@ -1018,10 +1018,10 @@ class MissingGroupedValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage.error('A useful error message'),
     ];
-    return ValidationResult(ValidationType.missing, messages);
+    return const ValidationResult(ValidationType.missing, messages);
   }
 }
 
@@ -1030,10 +1030,10 @@ class PartialGroupedValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage.error('An error message for partial installation'),
     ];
-    return ValidationResult(ValidationType.partial, messages);
+    return const ValidationResult(ValidationType.partial, messages);
   }
 }
 
@@ -1042,10 +1042,10 @@ class PassingGroupedValidatorWithStatus extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    final List<ValidationMessage> messages = <ValidationMessage>[
+    const List<ValidationMessage> messages = <ValidationMessage>[
       ValidationMessage('A different message'),
     ];
-    return ValidationResult(ValidationType.installed, messages, statusInfo: 'A status message');
+    return const ValidationResult(ValidationType.installed, messages, statusInfo: 'A status message');
   }
 }
 

packages/flutter_tools/test/general.shard/android/android_emulator_test.dart

@@ -31,7 +31,7 @@ void main() {
       const String emulatorID = '1234';
       final AndroidEmulator emulator = AndroidEmulator(
         emulatorID,
-        <String, String>{'name': 'test'},
+        const <String, String>{'name': 'test'},
       );
       expect(emulator.id, emulatorID);
       expect(emulator.hasConfig, true);

packages/flutter_tools/test/general.shard/base/fingerprint_test.dart

@@ -64,10 +64,10 @@ void main() {
         },
       );
       final Fingerprint fingerprint = fingerprinter.buildFingerprint();
-      expect(fingerprint, Fingerprint.fromBuildInputs(<String, String>{
+      expect(fingerprint, Fingerprint.fromBuildInputs(const <String, String>{
         'foo': 'bar',
         'wibble': 'wobble',
-      }, <String>['a.dart']));
+      }, const <String>['a.dart']));
     }, overrides: contextOverrides);
 
     testUsingContext('creates fingerprint with file checksums', () {
@@ -85,10 +85,10 @@ void main() {
         },
       );
       final Fingerprint fingerprint = fingerprinter.buildFingerprint();
-      expect(fingerprint, Fingerprint.fromBuildInputs(<String, String>{
+      expect(fingerprint, Fingerprint.fromBuildInputs(const <String, String>{
         'bar': 'baz',
         'wobble': 'womble',
-      }, <String>['a.dart', 'b.dart']));
+      }, const <String>['a.dart', 'b.dart']));
     }, overrides: contextOverrides);
 
     testUsingContext('fingerprint does not match if not present', () {
@@ -248,7 +248,7 @@ void main() {
       testUsingContext('throws if any input file does not exist', () {
         globals.fs.file('a.dart').createSync();
         expect(
-          () => Fingerprint.fromBuildInputs(<String, String>{}, <String>['a.dart', 'b.dart']),
+          () => Fingerprint.fromBuildInputs(const <String, String>{}, const <String>['a.dart', 'b.dart']),
           throwsException,
         );
       }, overrides: <Type, Generator>{
@@ -259,7 +259,7 @@ void main() {
       testUsingContext('populates checksums for valid files', () {
         globals.fs.file('a.dart').writeAsStringSync('This is a');
         globals.fs.file('b.dart').writeAsStringSync('This is b');
-        final Fingerprint fingerprint = Fingerprint.fromBuildInputs(<String, String>{}, <String>['a.dart', 'b.dart']);
+        final Fingerprint fingerprint = Fingerprint.fromBuildInputs(const <String, String>{}, const <String>['a.dart', 'b.dart']);
 
         final Map<String, dynamic> jsonObject = castStringKeyedMap(json.decode(fingerprint.toJson()));
         expect(jsonObject['files'], hasLength(2));
@@ -271,14 +271,14 @@ void main() {
       });
 
       testUsingContext('includes framework version', () {
-        final Fingerprint fingerprint = Fingerprint.fromBuildInputs(<String, String>{}, <String>[]);
+        final Fingerprint fingerprint = Fingerprint.fromBuildInputs(const <String, String>{}, const <String>[]);
 
         final Map<String, dynamic> jsonObject = castStringKeyedMap(json.decode(fingerprint.toJson()));
         expect(jsonObject['version'], mockVersion.frameworkRevision);
       }, overrides: <Type, Generator>{FlutterVersion: () => mockVersion});
 
       testUsingContext('includes provided properties', () {
-        final Fingerprint fingerprint = Fingerprint.fromBuildInputs(<String, String>{'a': 'A', 'b': 'B'}, <String>[]);
+        final Fingerprint fingerprint = Fingerprint.fromBuildInputs(const <String, String>{'a': 'A', 'b': 'B'}, const <String>[]);
 
         final Map<String, dynamic> jsonObject = castStringKeyedMap(json.decode(fingerprint.toJson()));
         expect(jsonObject['properties'], hasLength(2));
@@ -347,7 +347,7 @@ void main() {
         final String jsonString = json.encode(<String, dynamic>{
           'version': kVersion,
         });
-        expect(Fingerprint.fromJson(jsonString), Fingerprint.fromBuildInputs(<String, String>{}, <String>[]));
+        expect(Fingerprint.fromJson(jsonString), Fingerprint.fromBuildInputs(const <String, String>{}, const <String>[]));
       }, overrides: <Type, Generator>{
         FlutterVersion: () => mockVersion,
       });

packages/flutter_tools/test/general.shard/emulator_test.dart

@@ -45,11 +45,11 @@ void main() {
     });
 
     testUsingContext('getEmulatorsById', () async {
-      final _MockEmulator emulator1 =
+      const _MockEmulator emulator1 =
           _MockEmulator('Nexus_5', 'Nexus 5', 'Google');
-      final _MockEmulator emulator2 =
+      const _MockEmulator emulator2 =
           _MockEmulator('Nexus_5X_API_27_x86', 'Nexus 5X', 'Google');
-      final _MockEmulator emulator3 =
+      const _MockEmulator emulator3 =
           _MockEmulator('iOS Simulator', 'iOS Simulator', 'Apple');
       final List<Emulator> emulators = <Emulator>[
         emulator1,
@@ -137,7 +137,7 @@ void main() {
       });
     });
     testUsingContext('runs correct launch commands', () async {
-      final Emulator emulator = IOSEmulator('ios');
+      const Emulator emulator = IOSEmulator('ios');
       await emulator.launch();
       expect(didAttemptToRunSimulator, equals(true));
     }, overrides: <Type, Generator>{
@@ -160,7 +160,7 @@ class TestEmulatorManager extends EmulatorManager {
 }
 
 class _MockEmulator extends Emulator {
-  _MockEmulator(String id, this.name, this.manufacturer)
+  const _MockEmulator(String id, this.name, this.manufacturer)
     : super(id, true);
 
   @override

packages/flutter_tools/test/general.shard/linux/linux_doctor_test.dart

@@ -27,7 +27,7 @@ void main() {
     final ValidationResult result = await linuxDoctorValidator.validate();
 
     expect(result.type, ValidationType.installed);
-    expect(result.messages, <ValidationMessage>[
+    expect(result.messages, const <ValidationMessage>[
       ValidationMessage('clang++ 4.0.1'),
       ValidationMessage('GNU Make 4.1'),
     ]);
@@ -50,7 +50,7 @@ void main() {
     final ValidationResult result = await linuxDoctorValidator.validate();
 
     expect(result.type, ValidationType.partial);
-    expect(result.messages, <ValidationMessage>[
+    expect(result.messages, const <ValidationMessage>[
       ValidationMessage.error('clang++ 2.0.1 is below minimum version of 3.4.0'),
       ValidationMessage('GNU Make 4.1'),
     ]);
@@ -73,7 +73,7 @@ void main() {
     final ValidationResult result = await linuxDoctorValidator.validate();
 
     expect(result.type, ValidationType.missing);
-    expect(result.messages, <ValidationMessage>[
+    expect(result.messages, const <ValidationMessage>[
       ValidationMessage('clang++ 4.0.1'),
       ValidationMessage.error('make is not installed'),
     ]);
@@ -96,7 +96,7 @@ void main() {
     final ValidationResult result = await linuxDoctorValidator.validate();
 
     expect(result.type, ValidationType.missing);
-    expect(result.messages, <ValidationMessage>[
+    expect(result.messages, const <ValidationMessage>[
       ValidationMessage.error('clang++ is not installed'),
       ValidationMessage('GNU Make 4.1'),
     ]);

packages/flutter_tools/test/general.shard/web/web_validator_test.dart

@@ -63,7 +63,7 @@ void main() {
 
     final ValidationResult result = await webValidator.validate();
 
-    expect(result.messages, <ValidationMessage>[
+    expect(result.messages, const <ValidationMessage>[
       ValidationMessage.hint(
           'Cannot find Chrome. Try setting CHROME_EXECUTABLE to a Chrome executable.'),
     ]);