[material_ui] Set up m3e_gen_defaults sub-directory

packages/material_ui/pubspec.yaml

@@ -11,6 +11,7 @@ environment:
 
 workspace:
   - example
+  - tool/m3e_gen_defaults
 
 dependencies:
   cupertino_ui:

packages/material_ui/tool/m3e_gen_defaults/README.md

@@ -0,0 +1,24 @@
+## Token Defaults Generator
+
+Script that generates component theme data defaults based on token data.
+
+## Usage
+Run this program from the root of the git repository:
+```sh
+dart packages/material_ui/tool/m3e_gen_defaults/bin/gen_defaults.dart [-v]
+```
+
+This updates generated component theming files under
+`packages/material_ui/lib/src/m3e/generated`.
+
+## Templates
+
+There is a template file for every component that needs defaults from the token
+database. These templates are implemented as subclasses of `TokenTemplate`.
+
+Templates need to override the `generateContents` method to provide the
+generated code block as a string.
+
+## Tokens
+
+Tokens are stored in `data/`, and are sourced from an internal Google database.

packages/material_ui/tool/m3e_gen_defaults/analysis_options.yaml

@@ -0,0 +1,4 @@
+include: ../../../../analysis_options.yaml
+
+formatter:
+  page_width: 100

packages/material_ui/tool/m3e_gen_defaults/bin/gen_defaults.dart

@@ -0,0 +1,28 @@
+// 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.
+//
+// ## Usage
+//
+// Run from the root of flutter/packages:
+//
+// ```
+// dart packages/material_ui/tool/m3e_gen_defaults/bin/gen_defaults.dart [-v]
+// ```
+
+import 'package:args/args.dart';
+
+// TODO(elliette): Import template files.
+// import '../templates/x_template.dart';
+
+Future<void> main(List<String> args) async {
+  // Parse arguments
+  final parser = ArgParser();
+  parser.addFlag('verbose', abbr: 'v', help: 'Enable verbose output', negatable: false);
+  final ArgResults argResults = parser.parse(args);
+  // TODO(elliette): Add token logger when verbose flag is used.
+  // ignore: unused_local_variable
+  final verbose = argResults['verbose'] as bool;
+  // TODO(elliette): Invoke template generators.
+  // const XTemplate().generateFile(verbose: verbose);
+}

packages/material_ui/tool/m3e_gen_defaults/pubspec.yaml

@@ -0,0 +1,15 @@
+name: gen_defaults
+description: A command line script to generate Material component defaults from the token database.
+version: 1.0.0
+
+environment:
+  sdk: ^3.10.0-0
+
+resolution: workspace
+
+dependencies:
+  args: any
+
+dev_dependencies:
+  path: any
+  test: any

packages/material_ui/tool/m3e_gen_defaults/templates/template.dart

@@ -0,0 +1,78 @@
+// 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 'dart:io';
+
+abstract class TokenTemplate {
+  const TokenTemplate();
+
+  /// The name of the template, which corresponds to the target file name.
+  /// E.g., 'typography' for generating 'typography_defaults.g.dart'.
+  String get name;
+
+  static const String copyrightHeader = '''
+// 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.
+''';
+
+  static const String headerComment = '''
+
+// Do not edit by hand. The code is generated from data in the Material
+// Design token database by the script:
+//   packages/material_ui/tool/m3e_gen_defaults/bin/gen_defaults.dart.
+
+// dart format off
+''';
+
+  static const String footerComment = '''
+// dart format on
+''';
+
+  String generateContents();
+
+  void generateFile({bool verbose = false}) {
+    final fileName = '$materialLib/${name}_defaults.g.dart';
+    if (verbose) {
+      stdout.writeln('Generating file: $fileName');
+      stdout.writeln('Target parent file name: $name.dart');
+    }
+    final file = File(fileName);
+    if (!file.existsSync()) {
+      if (verbose) {
+        stdout.writeln('File does not exist, creating it.');
+      }
+      file.createSync(recursive: true);
+    }
+
+    final parentName = '$name.dart';
+
+    if (verbose) {
+      stdout.writeln('Generating contents...');
+    }
+    final buffer = StringBuffer();
+    buffer.write(copyrightHeader);
+    buffer.write(headerComment);
+    buffer.write("part of '../$parentName';\n\n");
+    buffer.write(generateContents());
+    buffer.write(footerComment);
+
+    if (verbose) {
+      stdout.writeln('Writing generated contents to $fileName...');
+    }
+    file.writeAsStringSync(buffer.toString());
+    if (verbose) {
+      stdout.writeln('Done generating $fileName.');
+    }
+  }
+
+  String get materialLib {
+    const packagePath = 'packages/material_ui';
+    const relativeOutputPath = 'lib/src/m3e/generated';
+    if (Directory(packagePath).existsSync()) {
+      return '$packagePath/$relativeOutputPath';
+    }
+    return relativeOutputPath;
+  }
+}

packages/material_ui/tool/m3e_gen_defaults/test/gen_defaults_test.dart

@@ -0,0 +1,77 @@
+// 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 'dart:io';
+
+import 'package:test/test.dart';
+import 'test_fixtures/button_template.dart';
+
+void main() {
+  group('TokenTemplate', () {
+    test(
+      'Templates will generate a part file ending in _defaults.g.dart with correct parent reference',
+      () {
+        final Directory tempDir = Directory.systemTemp.createTempSync('gen_defaults');
+        try {
+          final template = ButtonTemplate(tempDir.path);
+          template.generateFile();
+
+          final file = File('${tempDir.path}/button_defaults.g.dart');
+          expect(file.readAsStringSync(), '''
+// Copyright 2013 The Flutter Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Do not edit by hand. The code is generated from data in the Material
+// Design token database by the script:
+//   packages/material_ui/tool/m3e_gen_defaults/bin/gen_defaults.dart.
+
+// dart format off
+part of '../button.dart';
+
+abstract final class _ButtonDefaults {
+  static const double height = 40.0;
+  static const double borderRadius = 8.0;
+}
+// dart format on
+''');
+        } finally {
+          tempDir.deleteSync(recursive: true);
+        }
+      },
+    );
+
+    test('Templates will completely overwrite any previous code', () {
+      final Directory tempDir = Directory.systemTemp.createTempSync('gen_defaults');
+      try {
+        // Seed the file with pre-existing random text.
+        final file = File('${tempDir.path}/button_defaults.g.dart');
+        file.writeAsStringSync('Pre-existing random text.');
+
+        final templateNew = ButtonTemplate(tempDir.path);
+        templateNew.generateFile();
+        expect(file.readAsStringSync(), '''
+// 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.
+
+// Do not edit by hand. The code is generated from data in the Material
+// Design token database by the script:
+//   packages/material_ui/tool/m3e_gen_defaults/bin/gen_defaults.dart.
+
+// dart format off
+part of '../button.dart';
+
+abstract final class _ButtonDefaults {
+  static const double height = 40.0;
+  static const double borderRadius = 8.0;
+}
+// dart format on
+''');
+      } finally {
+        tempDir.deleteSync(recursive: true);
+      }
+    });
+  });
+}

packages/material_ui/tool/m3e_gen_defaults/test/test_fixtures/button_template.dart

@@ -0,0 +1,28 @@
+// 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 '../../templates/template.dart';
+import 'button_token_data.dart';
+
+class ButtonTemplate extends TokenTemplate {
+  ButtonTemplate(this.customMaterialLib);
+
+  final String customMaterialLib;
+
+  @override
+  String get name => 'button';
+
+  @override
+  String get materialLib => customMaterialLib;
+
+  @override
+  String generateContents() {
+    return '''
+abstract final class _ButtonDefaults {
+  static const double height = ${TokenButton.height};
+  static const double borderRadius = ${TokenButton.borderRadius};
+}
+''';
+  }
+}

packages/material_ui/tool/m3e_gen_defaults/test/test_fixtures/button_token_data.dart

@@ -0,0 +1,8 @@
+// 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.
+
+abstract final class TokenButton {
+  static const double height = 40.0;
+  static const double borderRadius = 8.0;
+}