[ci]Adds mechanism for packages to opt in to batched release

packages/go_router/ci_config.yaml

@@ -0,0 +1,3 @@
+release:
+  # TODO(chunhtai): Opt in when ready.
+  batch: false

packages/go_router_builder/ci_config.yaml

@@ -0,0 +1,3 @@
+release:
+  # TODO(chunhtai): Opt in when ready.
+  batch: false

script/tool/lib/src/common/repository_package.dart

@@ -60,6 +60,9 @@ class RepositoryPackage {
   /// The package's top-level README.
   File get authorsFile => directory.childFile('AUTHORS');
 
+  /// The package's top-level ci_config.yaml.
+  File get ciConfigFile => directory.childFile('ci_config.yaml');
+
   /// The lib directory containing the package's code.
   Directory get libDirectory => directory.childDirectory('lib');
 

script/tool/lib/src/repo_package_info_check_command.dart

@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 import 'package:file/file.dart';
+import 'package:yaml/yaml.dart';
 
 import 'common/core.dart';
 import 'common/output_utils.dart';
@@ -12,6 +13,12 @@ import 'common/repository_package.dart';
 const int _exitBadTableEntry = 3;
 const int _exitUnknownPackageEntry = 4;
 
+const Map<String, Object?> _validCiConfigSyntax = <String, Object?>{
+  'release': <String, Object?>{
+    'batch': <bool>{true, false}
+  },
+};
+
 /// A command to verify repository-level metadata about packages, such as
 /// repo README and CODEOWNERS entries.
 class RepoPackageInfoCheckCommand extends PackageLoopingCommand {
@@ -108,6 +115,12 @@ class RepoPackageInfoCheckCommand extends PackageLoopingCommand {
       errors.add('Missing CODEOWNERS entry');
     }
 
+    // The content of ci_config.yaml must be valid if there is one.
+    if (package.ciConfigFile.existsSync()) {
+      errors.addAll(
+          _validateCiConfig(package.ciConfigFile, mainPackage: package));
+    }
+
     // Any published package should be in the README table.
     // For federated plugins, only the app-facing package is listed.
     if (package.isPublishable() &&
@@ -190,6 +203,67 @@ class RepoPackageInfoCheckCommand extends PackageLoopingCommand {
         : PackageResult.fail(errors);
   }
 
+  List<String> _validateCiConfig(File ciConfig,
+      {required RepositoryPackage mainPackage}) {
+    print('${indentation}Checking '
+        '${getRelativePosixPath(ciConfig, from: mainPackage.directory)}...');
+    final YamlMap config;
+    try {
+      final Object? yaml = loadYaml(ciConfig.readAsStringSync());
+      if (yaml is! YamlMap) {
+        printError('${indentation}The ci_config.yaml file must be a map.');
+        return <String>['Root of config is not a map.'];
+      }
+      config = yaml;
+    } on YamlException catch (e) {
+      printError(
+          '${indentation}Invalid YAML in ${getRelativePosixPath(ciConfig, from: mainPackage.directory)}:');
+      printError(e.toString());
+      return <String>['Invalid YAML'];
+    }
+
+    return _checkCiConfigEntries(config, syntax: _validCiConfigSyntax);
+  }
+
+  List<String> _checkCiConfigEntries(YamlMap config,
+      {required Map<String, Object?> syntax, String configPrefix = ''}) {
+    final List<String> errors = <String>[];
+    for (final MapEntry<Object?, Object?> entry in config.entries) {
+      if (!syntax.containsKey(entry.key)) {
+        printError(
+            '${indentation}Unknown key `${entry.key}` in config${_formatConfigPrefix(configPrefix)}, the possible keys are ${syntax.keys.toList()}');
+        errors.add(
+            'Unknown key `${entry.key}` in config${_formatConfigPrefix(configPrefix)}');
+      } else {
+        final Object syntaxValue = syntax[entry.key]!;
+        configPrefix = configPrefix.isEmpty
+            ? entry.key! as String
+            : '$configPrefix.${entry.key}';
+        if (syntaxValue is Set) {
+          if (!syntaxValue.contains(entry.value)) {
+            printError(
+                '${indentation}Invalid value `${entry.value}` for key${_formatConfigPrefix(configPrefix)}, the possible values are ${syntaxValue.toList()}');
+            errors.add(
+                'Invalid value `${entry.value}` for key${_formatConfigPrefix(configPrefix)}');
+          }
+        } else if (entry.value is! YamlMap) {
+          printError(
+              '${indentation}Invalid value `${entry.value}` for key${_formatConfigPrefix(configPrefix)}, the value must be a map');
+          errors.add(
+              'Invalid value `${entry.value}` for key${_formatConfigPrefix(configPrefix)}');
+        } else {
+          errors.addAll(_checkCiConfigEntries(entry.value! as YamlMap,
+              syntax: syntaxValue as Map<String, Object?>,
+              configPrefix: configPrefix));
+        }
+      }
+    }
+    return errors;
+  }
+
+  String _formatConfigPrefix(String configPrefix) =>
+      configPrefix.isEmpty ? '' : ' `$configPrefix`';
+
   String _prTagForPackage(String packageName) => 'p: $packageName';
 
   String _issueTagForPackage(String packageName) {

script/tool/test/repo_package_info_check_command_test.dart

@@ -408,4 +408,113 @@ ${readmeTableEntry(packageName)}
               '    Missing CODEOWNERS entry')
         ]));
   });
+
+  group('ci_config check', () {
+    test('control test', () async {
+      final RepositoryPackage package =
+          createFakePackage('a_package', packagesDir);
+
+      root.childFile('README.md').writeAsStringSync('''
+${readmeTableHeader()}
+${readmeTableEntry('a_package')}
+''');
+      writeCodeOwners(<RepositoryPackage>[package]);
+
+      package.ciConfigFile.writeAsStringSync('''
+release:
+  batch: false
+    ''');
+
+      final List<String> output =
+          await runCapturingPrint(runner, <String>['repo-package-info-check']);
+
+      expect(
+        output,
+        containsAll(<Matcher>[
+          contains('  Checking ci_config.yaml...'),
+          contains('No issues found!'),
+        ]),
+      );
+    });
+
+    test('missing ci_config file is ok', () async {
+      final RepositoryPackage package =
+          createFakePackage('a_package', packagesDir);
+
+      root.childFile('README.md').writeAsStringSync('''
+${readmeTableHeader()}
+${readmeTableEntry('a_package')}
+''');
+      writeCodeOwners(<RepositoryPackage>[package]);
+
+      final List<String> output =
+          await runCapturingPrint(runner, <String>['repo-package-info-check']);
+
+      expect(
+        output,
+        containsAllInOrder(<Matcher>[
+          contains('No issues found!'),
+        ]),
+      );
+    });
+
+    test('fails for unknown key', () async {
+      final RepositoryPackage package =
+          createFakePackage('a_package', packagesDir);
+
+      root.childFile('README.md').writeAsStringSync('''
+${readmeTableHeader()}
+${readmeTableEntry('a_package')}
+''');
+      writeCodeOwners(<RepositoryPackage>[package]);
+      package.ciConfigFile.writeAsStringSync('''
+something: true
+    ''');
+
+      Error? commandError;
+      final List<String> output = await runCapturingPrint(
+          runner, <String>['repo-package-info-check'], errorHandler: (Error e) {
+        commandError = e;
+      });
+
+      expect(commandError, isA<ToolExit>());
+      expect(
+        output,
+        containsAllInOrder(<Matcher>[
+          contains('Unknown key `something` in config, the possible keys are'),
+        ]),
+      );
+    });
+
+    test('fails for invalid value type for batch property in release',
+        () async {
+      final RepositoryPackage package =
+          createFakePackage('a_package', packagesDir);
+
+      root.childFile('README.md').writeAsStringSync('''
+${readmeTableHeader()}
+${readmeTableEntry('a_package')}
+''');
+      writeCodeOwners(<RepositoryPackage>[package]);
+      package.ciConfigFile.writeAsStringSync('''
+release:
+  batch: 1
+    ''');
+
+      Error? commandError;
+      final List<String> output = await runCapturingPrint(
+          runner, <String>['repo-package-info-check'], errorHandler: (Error e) {
+        commandError = e;
+      });
+
+      expect(commandError, isA<ToolExit>());
+      expect(
+        output,
+        containsAllInOrder(<Matcher>[
+          contains(
+              'Invalid value `1` for key `release.batch`, the possible values are [true, false]'),
+        ]),
+      );
+    });
+  });
 }