Banner m3 defaults migration

packages/material_ui/lib/src/banner.dart

@@ -18,6 +18,8 @@ import 'scaffold.dart';
 import 'text_theme.dart';
 import 'theme.dart';
 
+part 'generated/banner_defaults_m3.g.dart';
+
 // Examples can assume:
 // late BuildContext context;
 
@@ -489,35 +491,3 @@ class _BannerDefaultsM2 extends MaterialBannerThemeData {
   @override
   TextStyle? get contentTextStyle => _theme.textTheme.bodyMedium;
 }
-
-// BEGIN GENERATED TOKEN PROPERTIES - Banner
-
-// Do not edit by hand. The code between the "BEGIN GENERATED" and
-// "END GENERATED" comments are generated from data in the Material
-// Design token database by the script:
-//   dev/tools/gen_defaults/bin/gen_defaults.dart.
-
-// dart format off
-class _BannerDefaultsM3 extends MaterialBannerThemeData {
-  _BannerDefaultsM3(this.context)
-    : super(elevation: 1.0);
-
-  final BuildContext context;
-  late final ColorScheme _colors = Theme.of(context).colorScheme;
-  late final TextTheme _textTheme = Theme.of(context).textTheme;
-
-  @override
-  Color? get backgroundColor => _colors.surfaceContainerLow;
-
-  @override
-  Color? get surfaceTintColor => Colors.transparent;
-
-  @override
-  Color? get dividerColor => _colors.outlineVariant;
-
-  @override
-  TextStyle? get contentTextStyle => _textTheme.bodyMedium;
-}
-// dart format on
-
-// END GENERATED TOKEN PROPERTIES - Banner

packages/material_ui/tool/gen_defaults/temporarily_excluded/generated/banner_defaults.g.dart → packages/material_ui/lib/src/generated/banner_defaults_m3.g.dart

@@ -2,6 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+// Do not edit by hand. The code is generated from data in the Material
+// Design token database by the script:
+//   packages/material_ui/tool/gen_defaults/bin/gen_defaults.dart.
+part of '../banner.dart';
+
 class _BannerDefaultsM3 extends MaterialBannerThemeData {
   _BannerDefaultsM3(this.context) : super(elevation: 1.0);
 

packages/material_ui/tool/gen_defaults/bin/gen_defaults.dart

@@ -13,6 +13,7 @@
 import 'package:args/args.dart';
 
 import '../templates/app_bar_template.dart';
+import '../templates/banner_template.dart';
 
 Future<void> main(List<String> args) async {
   // Parse arguments
@@ -22,4 +23,5 @@ Future<void> main(List<String> args) async {
   // TODO(elliette): Add token logger when verbose flag is used.
   final verbose = argResults['verbose'] as bool;
   const AppBarTemplateM3().generateFile(verbose: verbose);
+  const BannerTemplateM3().generateFile(verbose: verbose);
 }

packages/material_ui/tool/gen_defaults/templates/banner_template.dart

@@ -0,0 +1,42 @@
+// Copyright 2013 The Flutter Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import '../data/banner.dart';
+import '../data/divider.dart';
+import 'template.dart';
+
+class BannerTemplateM3 extends TokenTemplateM3 {
+  const BannerTemplateM3();
+
+  @override
+  String get name => 'Banner';
+
+  @override
+  String get parentFilePath => 'banner.dart';
+
+  @override
+  String generateContents(String className) =>
+      '''
+class $className extends MaterialBannerThemeData {
+  $className(this.context)
+    : super(elevation: ${number(TokenBanner.containerElevation)});
+
+  final BuildContext context;
+  late final ColorScheme _colors = Theme.of(context).colorScheme;
+  late final TextTheme _textTheme = Theme.of(context).textTheme;
+
+  @override
+  Color? get backgroundColor => ${color(TokenBanner.containerColor, '_colors')};
+
+  @override
+  Color? get surfaceTintColor => Colors.transparent;
+
+  @override
+  Color? get dividerColor => ${color(TokenDivider.color, '_colors')};
+
+  @override
+  TextStyle? get contentTextStyle => _textTheme.bodyMedium;
+}
+''';
+}

packages/material_ui/tool/gen_defaults/test/gen_defaults_test.dart

@@ -8,6 +8,7 @@ import 'package:test/test.dart';
 import '../data/color_role.dart';
 import '../data/shape_struct.dart';
 import '../templates/app_bar_template.dart';
+import '../templates/banner_template.dart';
 import '../templates/template.dart';
 import 'test_fixtures/test_templates.dart';
 
@@ -159,6 +160,17 @@ void main() {
       expect(contents, contains('static const double expandedHeight = 112.0'));
       expect(contents, contains('static const double expandedHeight = 152.0'));
     });
+
+    test('BannerTemplateM3 emits M3 Banner defaults from banner tokens', () {
+      final String contents = const BannerTemplateM3().generateContents('_BannerDefaultsM3');
+      expect(contents, contains('class _BannerDefaultsM3 extends MaterialBannerThemeData'));
+      expect(contents, contains('elevation: 1.0'));
+      expect(contents, contains('Color? get backgroundColor => _colors.surfaceContainerLow'));
+      expect(contents, contains('Color? get surfaceTintColor => Colors.transparent'));
+      expect(contents, contains('Color? get dividerColor => _colors.outlineVariant'));
+      expect(contents, contains('TextStyle? get contentTextStyle => _textTheme.bodyMedium'));
+    });
+
     test('will run dart format over the generated file', () {
       final template = UnformattedTemplate(testPath());
       template.generateFile();