Script to generate widget theme data defaults from the Material token database. (#95370)

dev/bots/test.dart

@@ -874,6 +874,7 @@ Future<void> _runFrameworkTests() async {
     await _runFlutterTest(path.join(flutterRoot, 'dev', 'integration_tests', 'android_semantics_testing'), fatalWarnings: false);
     await _runFlutterTest(path.join(flutterRoot, 'dev', 'manual_tests'));
     await _runFlutterTest(path.join(flutterRoot, 'dev', 'tools', 'vitool'));
+    await _runFlutterTest(path.join(flutterRoot, 'dev', 'tools', 'gen_defaults'));
     await _runFlutterTest(path.join(flutterRoot, 'dev', 'tools', 'gen_keycodes'));
     await _runFlutterTest(path.join(flutterRoot, 'dev', 'benchmarks', 'test_apps', 'stocks'));
     await _runFlutterTest(path.join(flutterRoot, 'packages', 'flutter_driver'), tests: <String>[path.join('test', 'src', 'real_tests')], options: soundNullSafetyOptions);

dev/tools/gen_defaults/README.md

+## Token Defaults Generator
+
+Script that generates widget component theme data defaults
+based on the Material Token database. These tokens were
+extracted into a JSON file from an internal Google database.
+
+## Usage
+Run this program from the root of the git repository:
+```
+dart dev/tools/gen_defaults/bin/gen_defaults.dart
+```
+
+## Templates
+
+There is a template file for every component that needs defaults from
+the token database. These templates are implemented as subclasses of
+`TokenTemplate`. This base class provides some utilities and a structure
+for adding a new chunk of generated code to the bottom of a given file.
+
+Templates need to override the `generate` method to provide the generated
+code chunk as a string. The tokens are represented as a `Map<String, dynamic>`
+that is loaded from `data/material-tokens.json`. Templates can look up
+whatever properties are needed in this structure to provide the properties
+needed for the component.
+
+See `lib/fab_template.dart` for an example that generates defaults for the
+Floating Action Button.

dev/tools/gen_defaults/bin/gen_defaults.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Generate component theme data defaults based on the Material
+// Design Token database. These tokens were extracted into a
+// JSON file from the internal Google database.
+//
+// ## Usage
+//
+// Run this program from the root of the git repository.
+//
+// ```
+// dart dev/tools/gen_defaults/bin/gen_defaults.dart
+// ```
+
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:gen_defaults/fab_template.dart';
+
+Future<void> main(List<String> args) async {
+  const String tokensDB = 'dev/tools/gen_defaults/data/material-tokens.json';
+  final Map<String, dynamic> tokens = jsonDecode(File(tokensDB).readAsStringSync()) as Map<String, dynamic>;
+
+  const String materialLib = 'packages/flutter/lib/src/material';
+
+  FABTemplate('$materialLib/floating_action_button.dart', tokens).updateFile();
+}

dev/tools/gen_defaults/lib/fab_template.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'template.dart';
+
+class FABTemplate extends TokenTemplate {
+  const FABTemplate(String fileName, Map<String, dynamic> tokens) : super(fileName, tokens);
+
+  @override
+  String generate() => '''
+// Generated version ${tokens["version"]}, ${tokens["date"]}
+class _M3Defaults extends FloatingActionButtonThemeData {
+  _M3Defaults(this.context, this.type, this.hasChild)
+    : _colors = Theme.of(context).colorScheme,
+      _textTheme = Theme.of(context).textTheme;
+
+  final BuildContext context;
+  final _FloatingActionButtonType type;
+  final bool hasChild;
+  final ColorScheme _colors;
+  final TextTheme _textTheme;
+
+  bool get _isExtended => type == _FloatingActionButtonType.extended;
+
+  @override Color? get foregroundColor => _colors.${color("md.comp.fab.primary.icon")};
+  @override Color? get backgroundColor => _colors.${color("md.comp.fab.primary.container")};
+  @override Color? get splashColor => _colors.${color("md.comp.fab.primary.pressed.state-layer")};
+  @override double get elevation => ${elevation("md.comp.fab.primary.container")};
+  @override Color? get focusColor => _colors.${color("md.comp.fab.primary.focus.state-layer")};
+  @override double get focusElevation => ${elevation("md.comp.fab.primary.focus.container")};
+  @override Color? get hoverColor => _colors.${color("md.comp.fab.primary.hover.state-layer")};
+  @override double get hoverElevation => ${elevation("md.comp.fab.primary.hover.container")};
+  @override double get highlightElevation => ${elevation("md.comp.fab.primary.pressed.container")};
+
+  @override
+  ShapeBorder? get shape {
+    switch (type) {
+      case _FloatingActionButtonType.regular:
+       return ${shape("md.comp.fab.primary.container.shape")};
+      case _FloatingActionButtonType.small:
+       return ${shape("md.comp.fab.primary.small.container.shape")};
+      case _FloatingActionButtonType.large:
+       return ${shape("md.comp.fab.primary.large.container.shape")};
+      case _FloatingActionButtonType.extended:
+       return ${shape("md.comp.extended-fab.primary.container.shape")};
+     }
+  }
+
+  @override bool? get enableFeedback => true;
+
+  @override
+  double? get iconSize {
+    switch (type) {
+      case _FloatingActionButtonType.regular: return ${value("md.comp.fab.primary.icon.size")};
+      case _FloatingActionButtonType.small: return  ${value("md.comp.fab.primary.small.icon.size")};
+      case _FloatingActionButtonType.large: return ${value("md.comp.fab.primary.large.icon.size")};
+      case _FloatingActionButtonType.extended: return ${value("md.comp.extended-fab.primary.icon.size")};
+    }
+  }
+
+  @override
+  BoxConstraints? get sizeConstraints => const BoxConstraints.tightFor(
+    width: ${value("md.comp.fab.primary.container.width")},
+    height: ${value("md.comp.fab.primary.container.height")},
+  );
+
+  @override
+  BoxConstraints? get smallSizeConstraints => const BoxConstraints.tightFor(
+    width: ${value("md.comp.fab.primary.small.container.width")},
+    height: ${value("md.comp.fab.primary.small.container.height")},
+  );
+
+  @override
+  BoxConstraints? get largeSizeConstraints => const BoxConstraints.tightFor(
+    width: ${value("md.comp.fab.primary.large.container.width")},
+    height: ${value("md.comp.fab.primary.large.container.height")},
+  );
+
+  @override
+  BoxConstraints? get extendedSizeConstraints => const BoxConstraints.tightFor(
+    height: ${value("md.comp.extended-fab.primary.container.height")},
+  );
+
+  @override double? get extendedIconLabelSpacing => 8.0;
+  @override EdgeInsetsGeometry? get extendedPadding => EdgeInsetsDirectional.only(start: hasChild && _isExtended ? 16.0 : 20.0, end: 20.0);
+  @override TextStyle? get extendedTextStyle => _textTheme.${textStyle("md.comp.extended-fab.primary.label-text")};
+}
+''';
+}

dev/tools/gen_defaults/lib/template.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io';
+
+abstract class TokenTemplate {
+  const TokenTemplate(this.fileName, this.tokens);
+
+  static const String beginGeneratedComment = '''
+
+// BEGIN GENERATED TOKEN PROPERTIES
+''';
+
+  static const String headerComment = '''
+
+// Generated code to the end of this file. Do not edit by hand.
+// These defaults are generated from the Material Design Token
+// database by the script dev/tools/gen_defaults/bin/gen_defaults.dart.
+
+''';
+
+  static const String endGeneratedComment = '''
+
+// END GENERATED TOKEN PROPERTIES
+''';
+
+  final String fileName;
+  final Map<String, dynamic> tokens;
+
+  /// Replace or append the contents of the file with the text from [generate].
+  ///
+  /// If the file already contains generated block at the end, it will
+  /// be replaced by the [generate] output. Otherwise the content will
+  /// just be appended to the end of the file.
+  Future<void> updateFile() async {
+    String contents = File(fileName).readAsStringSync();
+    final int previousGeneratedIndex = contents.indexOf(beginGeneratedComment);
+    if (previousGeneratedIndex != -1) {
+      contents = contents.substring(0, previousGeneratedIndex);
+    }
+    final StringBuffer buffer = StringBuffer(contents);
+    buffer.write(beginGeneratedComment);
+    buffer.write(headerComment);
+    buffer.write(generate());
+    buffer.write(endGeneratedComment);
+    File(fileName).writeAsStringSync(buffer.toString());
+  }
+
+  /// Provide the generated content for the template.
+  ///
+  /// This abstract method needs to be implemented by subclasses
+  /// to provide the content that [updateFile] will append to the
+  /// bottom of the file.
+  String generate();
+
+  String color(String tokenName) {
+    final String tokenColor = '$tokenName.color';
+    final String tokenOpacity = '$tokenName.opacity';
+    String value = '${tokens[tokenColor]!}';
+    if (tokens.containsKey(tokenOpacity)) {
+      final String opacity = tokens[tokens[tokenOpacity]!]!.toString();
+      value += '.withOpacity($opacity)';
+    }
+    return value;
+  }
+
+  String elevation(String tokenName) {
+    final String elevationName = '$tokenName.elevation';
+    final Map<String, dynamic> elevationValue = tokens[tokens[elevationName]!]! as Map<String, dynamic>;
+    return elevationValue['value']!.toString();
+  }
+
+  String shape(String tokenName) {
+    // TODO(darrenaustin): handle more than just rounded rectangle shapes
+    final String shapeToken = tokens[tokenName]! as String;
+    final Map<String, dynamic> shape = tokens[shapeToken]! as Map<String, dynamic>;
+    final Map<String, dynamic> shapeValue = shape['value']! as Map<String, dynamic>;
+    return 'const RoundedRectangleBorder(borderRadius: BorderRadius.all(Radius.circular(${shapeValue['value']!})))';
+  }
+
+  String value(String tokenName) {
+    final Map<String, dynamic> value = tokens[tokenName]! as Map<String, dynamic>;
+    return value['value'].toString();
+  }
+
+  String textStyle(String tokenName) {
+    final String fontName = '$tokenName.font';
+    return tokens[fontName]!.toString();
+  }
+}

dev/tools/gen_defaults/pubspec.yaml

+name: gen_defaults
+description: A command line script to generate Material component defaults from the token database.
+version: 1.0.0
+
+environment:
+  sdk: ">=2.12.0-0 <3.0.0"
+
+dependencies:
+
+  async: 2.8.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  charcode: 1.3.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  collection: 1.15.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  http_parser: 4.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  source_span: 1.8.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  string_scanner: 1.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  term_glyph: 1.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  typed_data: 1.3.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+
+dev_dependencies:
+  path: 1.8.0
+  test: 1.19.5
+
+  _fe_analyzer_shared: 31.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  analyzer: 2.8.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  boolean_selector: 2.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  cli_util: 0.3.5 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  convert: 3.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  coverage: 1.0.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  crypto: 3.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  file: 6.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  frontend_server_client: 2.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  glob: 2.0.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  http_multi_server: 3.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  io: 1.0.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  js: 0.6.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  logging: 1.0.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  matcher: 0.12.11 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  mime: 1.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  node_preamble: 2.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  package_config: 2.0.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  pool: 1.5.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  pub_semver: 2.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf: 1.1.4 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf_packages_handler: 3.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf_static: 1.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  shelf_web_socket: 1.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  source_map_stack_trace: 2.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  source_maps: 0.10.10 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  stack_trace: 1.10.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  stream_channel: 2.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  test_core: 0.4.9 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  vm_service: 7.5.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  watcher: 1.0.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  web_socket_channel: 2.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  webkit_inspection_protocol: 1.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  yaml: 3.1.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+
+# PUBSPEC CHECKSUM: aa20

dev/tools/gen_defaults/test/gen_defaults_test.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:io';
+
+import 'package:gen_defaults/template.dart';
+import 'package:path/path.dart' as path;
+import 'package:test/test.dart';
+
+void main() {
+  test('Templates will append to the end of a file', () {
+    final Directory tempDir = Directory.systemTemp.createTempSync('gen_defaults');
+    try {
+      // Create a temporary file with some content.
+      final File tempFile = File(path.join(tempDir.path, 'test_template.txt'));
+      tempFile.createSync();
+      tempFile.writeAsStringSync('''
+// This is a file with stuff in it.
+// This part shouldn't be changed by
+// the template.
+''');
+
+      // Have a test template append new parameterized content to the end of
+      // the file.
+      final Map<String, dynamic> tokens = <String, dynamic>{'foo': 'Foobar', 'bar': 'Barfoo'};
+      TestTemplate(tempFile.path, tokens).updateFile();
+
+      expect(tempFile.readAsStringSync(), '''
+// This is a file with stuff in it.
+// This part shouldn't be changed by
+// the template.
+
+// BEGIN GENERATED TOKEN PROPERTIES
+
+// Generated code to the end of this file. Do not edit by hand.
+// These defaults are generated from the Material Design Token
+// database by the script dev/tools/gen_defaults/bin/gen_defaults.dart.
+
+static final String tokenFoo = 'Foobar';
+static final String tokenBar = 'Barfoo';
+
+// END GENERATED TOKEN PROPERTIES
+''');
+
+    } finally {
+      tempDir.deleteSync(recursive: true);
+    }
+  });
+
+  test('Templates will update over previously generated code at the end of a file', () {
+    final Directory tempDir = Directory.systemTemp.createTempSync('gen_defaults');
+    try {
+      // Create a temporary file with some content.
+      final File tempFile = File(path.join(tempDir.path, 'test_template.txt'));
+      tempFile.createSync();
+      tempFile.writeAsStringSync('''
+// This is a file with stuff in it.
+// This part shouldn't be changed by
+// the template.
+
+// BEGIN GENERATED TOKEN PROPERTIES
+
+// Generated code to the end of this file. Do not edit by hand.
+// These defaults are generated from the Material Design Token
+// database by the script dev/tools/gen_defaults/bin/gen_defaults.dart.
+
+static final String tokenFoo = 'Foobar';
+static final String tokenBar = 'Barfoo';
+
+// END GENERATED TOKEN PROPERTIES
+''');
+
+      // Have a test template append new parameterized content to the end of
+      // the file.
+      final Map<String, dynamic> tokens = <String, dynamic>{'foo': 'foo', 'bar': 'bar'};
+      TestTemplate(tempFile.path, tokens).updateFile();
+
+      expect(tempFile.readAsStringSync(), '''
+// This is a file with stuff in it.
+// This part shouldn't be changed by
+// the template.
+
+// BEGIN GENERATED TOKEN PROPERTIES
+
+// Generated code to the end of this file. Do not edit by hand.
+// These defaults are generated from the Material Design Token
+// database by the script dev/tools/gen_defaults/bin/gen_defaults.dart.
+
+static final String tokenFoo = 'foo';
+static final String tokenBar = 'bar';
+
+// END GENERATED TOKEN PROPERTIES
+''');
+
+    } finally {
+      tempDir.deleteSync(recursive: true);
+    }
+  });
+}
+
+class TestTemplate extends TokenTemplate {
+  TestTemplate(String fileName, Map<String, dynamic> tokens) : super(fileName, tokens);
+
+  @override
+  String generate() => '''
+static final String tokenFoo = '${tokens['foo']}';
+static final String tokenBar = '${tokens['bar']}';
+''';
+}