script/tool/lib/src/gradle_check_command.dart - mirrors/packages - Git at Google

 // Copyright 2013 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 'package:file/file.dart';
 import 'package:meta/meta.dart';
 import 'package:pub_semver/pub_semver.dart';

 import 'common/core.dart';
 import 'common/output_utils.dart';
 import 'common/package_looping_command.dart';
 import 'common/plugin_utils.dart';
 import 'common/repository_package.dart';

 /// The lowest `ext.kotlin_version` that example apps are allowed to use.
 @visibleForTesting
 final Version minKotlinVersion = Version(1, 7, 10);

 /// A command to enforce gradle file conventions and best practices.
 class GradleCheckCommand extends PackageLoopingCommand {
   /// Creates an instance of the gradle check command.
   GradleCheckCommand(super.packagesDir);

   @override
   final String name = 'gradle-check';

   @override
   List<String> get aliases => <String>['check-gradle'];

   @override
   final String description =
       'Checks that gradle files follow repository conventions.';

   @override
   bool get hasLongOutput => false;

   @override
   PackageLoopingType get packageLoopingType =>
       PackageLoopingType.includeAllSubpackages;

   @override
   Future<PackageResult> runForPackage(RepositoryPackage package) async {
     if (!package.platformDirectory(FlutterPlatform.android).existsSync()) {
       return PackageResult.skip('No android/ directory.');
     }

     const String exampleDirName = 'example';
     final bool isExample = package.directory.basename == exampleDirName ||
         package.directory.parent.basename == exampleDirName;
     if (!_validateBuildGradles(package, isExample: isExample)) {
       return PackageResult.fail();
     }
     return PackageResult.success();
   }

   bool _validateBuildGradles(RepositoryPackage package,
       {required bool isExample}) {
     final Directory androidDir =
         package.platformDirectory(FlutterPlatform.android);
     final File topLevelGradleFile = _getBuildGradleFile(androidDir);

     // This is tracked as a variable rather than a sequence of &&s so that all
     // failures are reported at once, not just the first one.
     bool succeeded = true;
     if (isExample) {
       if (!_validateExampleTopLevelBuildGradle(package, topLevelGradleFile)) {
         succeeded = false;
       }

       final File appGradleFile =
           _getBuildGradleFile(androidDir.childDirectory('app'));
       if (!_validateExampleAppBuildGradle(package, appGradleFile)) {
         succeeded = false;
       }
     } else {
       succeeded = _validatePluginBuildGradle(package, topLevelGradleFile);
     }

     return succeeded;
   }

   // Returns the gradle file in the given directory.
   File _getBuildGradleFile(Directory dir) => dir.childFile('build.gradle');

   // Returns the main/AndroidManifest.xml file for the given package.
   File _getMainAndroidManifest(RepositoryPackage package,
       {required bool isExample}) {
     final Directory androidDir =
         package.platformDirectory(FlutterPlatform.android);
     final Directory baseDir =
         isExample ? androidDir.childDirectory('app') : androidDir;
     return baseDir
         .childDirectory('src')
         .childDirectory('main')
         .childFile('AndroidManifest.xml');
   }

   bool _isCommented(String line) => line.trim().startsWith('//');

   /// Validates the build.gradle file for a plugin
   /// (some_plugin/android/build.gradle).
   bool _validatePluginBuildGradle(RepositoryPackage package, File gradleFile) {
     print('${indentation}Validating '
         '${getRelativePosixPath(gradleFile, from: package.directory)}.');
     final String contents = gradleFile.readAsStringSync();
     final List<String> lines = contents.split('\n');

     // This is tracked as a variable rather than a sequence of &&s so that all
     // failures are reported at once, not just the first one.
     bool succeeded = true;
     if (!_validateNamespace(package, contents, isExample: false)) {
       succeeded = false;
     }
     if (!_validateCompatibilityVersions(lines)) {
       succeeded = false;
     }
     if (!_validateGradleDrivenLintConfig(package, lines)) {
       succeeded = false;
     }
     return succeeded;
   }

   /// Validates the top-level build.gradle for an example app (e.g.,
   /// some_package/example/android/build.gradle).
   bool _validateExampleTopLevelBuildGradle(
       RepositoryPackage package, File gradleFile) {
     print('${indentation}Validating '
         '${getRelativePosixPath(gradleFile, from: package.directory)}.');
     final String contents = gradleFile.readAsStringSync();
     final List<String> lines = contents.split('\n');

     // This is tracked as a variable rather than a sequence of &&s so that all
     // failures are reported at once, not just the first one.
     bool succeeded = true;
     if (!_validateJavacLintConfig(package, lines)) {
       succeeded = false;
     }
     if (!_validateKotlinVersion(package, lines)) {
       succeeded = false;
     }
     return succeeded;
   }

   /// Validates the app-level build.gradle for an example app (e.g.,
   /// some_package/example/android/app/build.gradle).
   bool _validateExampleAppBuildGradle(
       RepositoryPackage package, File gradleFile) {
     print('${indentation}Validating '
         '${getRelativePosixPath(gradleFile, from: package.directory)}.');
     final String contents = gradleFile.readAsStringSync();

     // This is tracked as a variable rather than a sequence of &&s so that all
     // failures are reported at once, not just the first one.
     bool succeeded = true;
     if (!_validateNamespace(package, contents, isExample: true)) {
       succeeded = false;
     }
     return succeeded;
   }

   /// Validates that [gradleContents] sets a namespace, which is required for
   /// compatibility with apps that use AGP 8+.
   bool _validateNamespace(RepositoryPackage package, String gradleContents,
       {required bool isExample}) {
     final RegExp namespaceRegex =
         RegExp('^\\s*namespace\\s+[\'"](.*?)[\'"]', multiLine: true);
     final RegExpMatch? namespaceMatch =
         namespaceRegex.firstMatch(gradleContents);

     // For plugins, make sure the namespace is conditionalized so that it
     // doesn't break client apps using AGP 4.1 and earlier (which don't have
     // a namespace property, and will fail to build if it's set).
     const String namespaceConditional =
         'if (project.android.hasProperty("namespace"))';
     String exampleSetNamespace = "namespace 'dev.flutter.foo'";
     if (!isExample) {
       exampleSetNamespace = '''
 $namespaceConditional {
     $exampleSetNamespace
 }''';
     }
     // Wrap the namespace command in an `android` block, adding the indentation
     // to make it line up correctly.
     final String exampleAndroidNamespaceBlock = '''
     android {
         ${exampleSetNamespace.split('\n').join('\n        ')}
     }
 ''';

     if (namespaceMatch == null) {
       final String errorMessage = '''
 build.gradle must set a "namespace":

 $exampleAndroidNamespaceBlock

 The value must match the "package" attribute in AndroidManifest.xml, if one is
 present. For more information, see:
 https://developer.android.com/build/publish-library/prep-lib-release#choose-namespace
 ''';

       printError(
           '$indentation${errorMessage.split('\n').join('\n$indentation')}');
       return false;
     } else {
       if (!isExample && !gradleContents.contains(namespaceConditional)) {
         final String errorMessage = '''
 build.gradle for a plugin must conditionalize "namespace":

 $exampleAndroidNamespaceBlock
 ''';

         printError(
             '$indentation${errorMessage.split('\n').join('\n$indentation')}');
         return false;
       }

       return _validateNamespaceMatchesManifest(package,
           isExample: isExample, namespace: namespaceMatch.group(1)!);
     }
   }

   /// Validates that the given namespace matches the manifest package of
   /// [package] (if any; a package does not need to be in the manifest in cases
   /// where compatibility with AGP <7 is no longer required).
   ///
   /// Prints an error and returns false if validation fails.
   bool _validateNamespaceMatchesManifest(RepositoryPackage package,
       {required bool isExample, required String namespace}) {
     final RegExp manifestPackageRegex = RegExp(r'package\s*=\s*"(.*?)"');
     final String manifestContents =
         _getMainAndroidManifest(package, isExample: isExample)
             .readAsStringSync();
     final RegExpMatch? packageMatch =
         manifestPackageRegex.firstMatch(manifestContents);
     if (packageMatch != null && namespace != packageMatch.group(1)) {
       final String errorMessage = '''
 build.gradle "namespace" must match the "package" attribute in AndroidManifest.xml, if one is present.
   build.gradle namespace: "$namespace"
   AndroidMastifest.xml package: "${packageMatch.group(1)}"
 ''';
       printError(
           '$indentation${errorMessage.split('\n').join('\n$indentation')}');
       return false;
     }
     return true;
   }

   /// Checks for a source compatibiltiy version, so that it's explicit rather
   /// than using whatever the client's local toolchaing defaults to (which can
   /// lead to compile errors that show up for clients, but not in CI).
   bool _validateCompatibilityVersions(List<String> gradleLines) {
     final bool hasLanguageVersion = gradleLines.any((String line) =>
         line.contains('languageVersion') && !_isCommented(line));
     final bool hasCompabilityVersions = gradleLines.any((String line) =>
             line.contains('sourceCompatibility') && !_isCommented(line)) &&
         // Newer toolchains default targetCompatibility to the same value as
         // sourceCompatibility, but older toolchains require it to be set
         // explicitly. The exact version cutoff (and of which piece of the
         // toolchain; likely AGP) is unknown; for context see
         // https://github.com/flutter/flutter/issues/125482
         gradleLines.any((String line) =>
             line.contains('targetCompatibility') && !_isCommented(line));
     if (!hasLanguageVersion && !hasCompabilityVersions) {
       const String errorMessage = '''
 build.gradle must set an explicit Java compatibility version.

 This can be done either via "sourceCompatibility"/"targetCompatibility":
     android {
         compileOptions {
             sourceCompatibility JavaVersion.VERSION_1_8
             targetCompatibility JavaVersion.VERSION_1_8
         }
     }

 or "toolchain":
     java {
         toolchain {
             languageVersion = JavaLanguageVersion.of(8)
         }
     }

 See:
 https://docs.gradle.org/current/userguide/java_plugin.html#toolchain_and_compatibility
 for more details.''';

       printError(
           '$indentation${errorMessage.split('\n').join('\n$indentation')}');
       return false;
     }
     return true;
   }

   /// Returns whether the given gradle content is configured to enable all
   /// Gradle-driven lints (those checked by ./gradlew lint) and treat them as
   /// errors.
   bool _validateGradleDrivenLintConfig(
       RepositoryPackage package, List<String> gradleLines) {
     final List<String> gradleBuildContents = package
         .platformDirectory(FlutterPlatform.android)
         .childFile('build.gradle')
         .readAsLinesSync();
     if (!gradleBuildContents.any((String line) =>
             line.contains('checkAllWarnings true') && !_isCommented(line)) ||
         !gradleBuildContents.any((String line) =>
             line.contains('warningsAsErrors true') && !_isCommented(line))) {
       printError('${indentation}This package is not configured to enable all '
           'Gradle-driven lint warnings and treat them as errors. '
           'Please add the following to the lintOptions section of '
           'android/build.gradle:');
       print('''
         checkAllWarnings true
         warningsAsErrors true
 ''');
       return false;
     }
     return true;
   }

   /// Validates whether the given [example]'s gradle content is configured to
   /// build its plugin target with javac lints enabled and treated as errors,
   /// if the enclosing package is a plugin.
   ///
   /// This can only be called on example packages. (Plugin packages should not
   /// be configured this way, since it would affect clients.)
   ///
   /// If [example]'s enclosing package is not a plugin package, this just
   /// returns true.
   bool _validateJavacLintConfig(
       RepositoryPackage example, List<String> gradleLines) {
     final RepositoryPackage enclosingPackage = example.getEnclosingPackage()!;
     if (!pluginSupportsPlatform(platformAndroid, enclosingPackage,
         requiredMode: PlatformSupport.inline)) {
       return true;
     }
     final String enclosingPackageName = enclosingPackage.directory.basename;

     // The check here is intentionally somewhat loose, to allow for the
     // possibility of variations (e.g., not using Xlint:all in some cases, or
     // passing other arguments).
     if (!(gradleLines.any((String line) =>
             line.contains('project(":$enclosingPackageName")')) &&
         gradleLines.any((String line) =>
             line.contains('options.compilerArgs') &&
             line.contains('-Xlint') &&
             line.contains('-Werror')))) {
       printError('The example '
           '"${getRelativePosixPath(example.directory, from: enclosingPackage.directory)}" '
           'is not configured to treat javac lints and warnings as errors. '
           'Please add the following to its build.gradle:');
       print('''
 gradle.projectsEvaluated {
     project(":$enclosingPackageName") {
         tasks.withType(JavaCompile) {
             options.compilerArgs << "-Xlint:all" << "-Werror"
         }
     }
 }
 ''');
       return false;
     }
     return true;
   }

   /// Validates whether the given [example] has its Kotlin version set to at
   /// least a minimum value, if it is set at all.
   bool _validateKotlinVersion(
       RepositoryPackage example, List<String> gradleLines) {
     final RegExp kotlinVersionRegex =
         RegExp(r"ext\.kotlin_version\s*=\s*'([\d.]+)'");
     RegExpMatch? match;
     if (gradleLines.any((String line) {
       match = kotlinVersionRegex.firstMatch(line);
       return match != null;
     })) {
       final Version version = Version.parse(match!.group(1)!);
       if (version < minKotlinVersion) {
         printError('build.gradle sets "ext.kotlin_version" to "$version". The '
             'minimum Kotlin version that can be specified is '
             '$minKotlinVersion, for compatibility with modern dependencies.');
         return false;
       }
     }
     return true;
   }
 }
	// Copyright 2013 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 'package:file/file.dart';
	import 'package:meta/meta.dart';
	import 'package:pub_semver/pub_semver.dart';

	import 'common/core.dart';
	import 'common/output_utils.dart';
	import 'common/package_looping_command.dart';
	import 'common/plugin_utils.dart';
	import 'common/repository_package.dart';

	/// The lowest `ext.kotlin_version` that example apps are allowed to use.
	@visibleForTesting
	final Version minKotlinVersion = Version(1, 7, 10);

	/// A command to enforce gradle file conventions and best practices.
	class GradleCheckCommand extends PackageLoopingCommand {
	/// Creates an instance of the gradle check command.
	GradleCheckCommand(super.packagesDir);

	@override
	final String name = 'gradle-check';

	@override
	List<String> get aliases => <String>['check-gradle'];

	@override
	final String description =
	'Checks that gradle files follow repository conventions.';

	@override
	bool get hasLongOutput => false;

	@override
	PackageLoopingType get packageLoopingType =>
	PackageLoopingType.includeAllSubpackages;

	@override
	Future<PackageResult> runForPackage(RepositoryPackage package) async {
	if (!package.platformDirectory(FlutterPlatform.android).existsSync()) {
	return PackageResult.skip('No android/ directory.');
	}

	const String exampleDirName = 'example';
	final bool isExample = package.directory.basename == exampleDirName \|\|
	package.directory.parent.basename == exampleDirName;
	if (!_validateBuildGradles(package, isExample: isExample)) {
	return PackageResult.fail();
	}
	return PackageResult.success();
	}

	bool _validateBuildGradles(RepositoryPackage package,
	{required bool isExample}) {
	final Directory androidDir =
	package.platformDirectory(FlutterPlatform.android);
	final File topLevelGradleFile = _getBuildGradleFile(androidDir);

	// This is tracked as a variable rather than a sequence of &&s so that all
	// failures are reported at once, not just the first one.
	bool succeeded = true;
	if (isExample) {
	if (!_validateExampleTopLevelBuildGradle(package, topLevelGradleFile)) {
	succeeded = false;
	}

	final File appGradleFile =
	_getBuildGradleFile(androidDir.childDirectory('app'));
	if (!_validateExampleAppBuildGradle(package, appGradleFile)) {
	succeeded = false;
	}
	} else {
	succeeded = _validatePluginBuildGradle(package, topLevelGradleFile);
	}

	return succeeded;
	}

	// Returns the gradle file in the given directory.
	File _getBuildGradleFile(Directory dir) => dir.childFile('build.gradle');

	// Returns the main/AndroidManifest.xml file for the given package.
	File _getMainAndroidManifest(RepositoryPackage package,
	{required bool isExample}) {
	final Directory androidDir =
	package.platformDirectory(FlutterPlatform.android);
	final Directory baseDir =
	isExample ? androidDir.childDirectory('app') : androidDir;
	return baseDir
	.childDirectory('src')
	.childDirectory('main')
	.childFile('AndroidManifest.xml');
	}

	bool _isCommented(String line) => line.trim().startsWith('//');

	/// Validates the build.gradle file for a plugin
	/// (some_plugin/android/build.gradle).
	bool _validatePluginBuildGradle(RepositoryPackage package, File gradleFile) {
	print('${indentation}Validating '
	'${getRelativePosixPath(gradleFile, from: package.directory)}.');
	final String contents = gradleFile.readAsStringSync();
	final List<String> lines = contents.split('\n');

	// This is tracked as a variable rather than a sequence of &&s so that all
	// failures are reported at once, not just the first one.
	bool succeeded = true;
	if (!_validateNamespace(package, contents, isExample: false)) {
	succeeded = false;
	}
	if (!_validateCompatibilityVersions(lines)) {
	succeeded = false;
	}
	if (!_validateGradleDrivenLintConfig(package, lines)) {
	succeeded = false;
	}
	return succeeded;
	}

	/// Validates the top-level build.gradle for an example app (e.g.,
	/// some_package/example/android/build.gradle).
	bool _validateExampleTopLevelBuildGradle(
	RepositoryPackage package, File gradleFile) {
	print('${indentation}Validating '
	'${getRelativePosixPath(gradleFile, from: package.directory)}.');
	final String contents = gradleFile.readAsStringSync();
	final List<String> lines = contents.split('\n');

	// This is tracked as a variable rather than a sequence of &&s so that all
	// failures are reported at once, not just the first one.
	bool succeeded = true;
	if (!_validateJavacLintConfig(package, lines)) {
	succeeded = false;
	}
	if (!_validateKotlinVersion(package, lines)) {
	succeeded = false;
	}
	return succeeded;
	}

	/// Validates the app-level build.gradle for an example app (e.g.,
	/// some_package/example/android/app/build.gradle).
	bool _validateExampleAppBuildGradle(
	RepositoryPackage package, File gradleFile) {
	print('${indentation}Validating '
	'${getRelativePosixPath(gradleFile, from: package.directory)}.');
	final String contents = gradleFile.readAsStringSync();

	// This is tracked as a variable rather than a sequence of &&s so that all
	// failures are reported at once, not just the first one.
	bool succeeded = true;
	if (!_validateNamespace(package, contents, isExample: true)) {
	succeeded = false;
	}
	return succeeded;
	}

	/// Validates that [gradleContents] sets a namespace, which is required for
	/// compatibility with apps that use AGP 8+.
	bool _validateNamespace(RepositoryPackage package, String gradleContents,
	{required bool isExample}) {
	final RegExp namespaceRegex =
	RegExp('^\\snamespace\\s+[\'"](.?)[\'"]', multiLine: true);
	final RegExpMatch? namespaceMatch =
	namespaceRegex.firstMatch(gradleContents);

	// For plugins, make sure the namespace is conditionalized so that it
	// doesn't break client apps using AGP 4.1 and earlier (which don't have
	// a namespace property, and will fail to build if it's set).
	const String namespaceConditional =
	'if (project.android.hasProperty("namespace"))';
	String exampleSetNamespace = "namespace 'dev.flutter.foo'";
	if (!isExample) {
	exampleSetNamespace = '''
	$namespaceConditional {
	$exampleSetNamespace
	}''';
	}
	// Wrap the namespace command in an `android` block, adding the indentation
	// to make it line up correctly.
	final String exampleAndroidNamespaceBlock = '''
	android {
	${exampleSetNamespace.split('\n').join('\n ')}
	}
	''';

	if (namespaceMatch == null) {
	final String errorMessage = '''
	build.gradle must set a "namespace":

	$exampleAndroidNamespaceBlock

	The value must match the "package" attribute in AndroidManifest.xml, if one is
	present. For more information, see:
	https://developer.android.com/build/publish-library/prep-lib-release#choose-namespace
	''';

	printError(
	'$indentation${errorMessage.split('\n').join('\n$indentation')}');
	return false;
	} else {
	if (!isExample && !gradleContents.contains(namespaceConditional)) {
	final String errorMessage = '''
	build.gradle for a plugin must conditionalize "namespace":

	$exampleAndroidNamespaceBlock
	''';

	printError(
	'$indentation${errorMessage.split('\n').join('\n$indentation')}');
	return false;
	}

	return _validateNamespaceMatchesManifest(package,
	isExample: isExample, namespace: namespaceMatch.group(1)!);
	}
	}

	/// Validates that the given namespace matches the manifest package of
	/// [package] (if any; a package does not need to be in the manifest in cases
	/// where compatibility with AGP <7 is no longer required).
	///
	/// Prints an error and returns false if validation fails.
	bool _validateNamespaceMatchesManifest(RepositoryPackage package,
	{required bool isExample, required String namespace}) {
	final RegExp manifestPackageRegex = RegExp(r'package\s=\s"(.*?)"');
	final String manifestContents =
	_getMainAndroidManifest(package, isExample: isExample)
	.readAsStringSync();
	final RegExpMatch? packageMatch =
	manifestPackageRegex.firstMatch(manifestContents);
	if (packageMatch != null && namespace != packageMatch.group(1)) {
	final String errorMessage = '''
	build.gradle "namespace" must match the "package" attribute in AndroidManifest.xml, if one is present.
	build.gradle namespace: "$namespace"
	AndroidMastifest.xml package: "${packageMatch.group(1)}"
	''';
	printError(
	'$indentation${errorMessage.split('\n').join('\n$indentation')}');
	return false;
	}
	return true;
	}

	/// Checks for a source compatibiltiy version, so that it's explicit rather
	/// than using whatever the client's local toolchaing defaults to (which can
	/// lead to compile errors that show up for clients, but not in CI).
	bool _validateCompatibilityVersions(List<String> gradleLines) {
	final bool hasLanguageVersion = gradleLines.any((String line) =>
	line.contains('languageVersion') && !_isCommented(line));
	final bool hasCompabilityVersions = gradleLines.any((String line) =>
	line.contains('sourceCompatibility') && !_isCommented(line)) &&
	// Newer toolchains default targetCompatibility to the same value as
	// sourceCompatibility, but older toolchains require it to be set
	// explicitly. The exact version cutoff (and of which piece of the
	// toolchain; likely AGP) is unknown; for context see
	// https://github.com/flutter/flutter/issues/125482
	gradleLines.any((String line) =>
	line.contains('targetCompatibility') && !_isCommented(line));
	if (!hasLanguageVersion && !hasCompabilityVersions) {
	const String errorMessage = '''
	build.gradle must set an explicit Java compatibility version.

	This can be done either via "sourceCompatibility"/"targetCompatibility":
	android {
	compileOptions {
	sourceCompatibility JavaVersion.VERSION_1_8
	targetCompatibility JavaVersion.VERSION_1_8
	}
	}

	or "toolchain":
	java {
	toolchain {
	languageVersion = JavaLanguageVersion.of(8)
	}
	}

	See:
	https://docs.gradle.org/current/userguide/java_plugin.html#toolchain_and_compatibility
	for more details.''';

	printError(
	'$indentation${errorMessage.split('\n').join('\n$indentation')}');
	return false;
	}
	return true;
	}

	/// Returns whether the given gradle content is configured to enable all
	/// Gradle-driven lints (those checked by ./gradlew lint) and treat them as
	/// errors.
	bool _validateGradleDrivenLintConfig(
	RepositoryPackage package, List<String> gradleLines) {
	final List<String> gradleBuildContents = package
	.platformDirectory(FlutterPlatform.android)
	.childFile('build.gradle')
	.readAsLinesSync();
	if (!gradleBuildContents.any((String line) =>
	line.contains('checkAllWarnings true') && !_isCommented(line)) \|\|
	!gradleBuildContents.any((String line) =>
	line.contains('warningsAsErrors true') && !_isCommented(line))) {
	printError('${indentation}This package is not configured to enable all '
	'Gradle-driven lint warnings and treat them as errors. '
	'Please add the following to the lintOptions section of '
	'android/build.gradle:');
	print('''
	checkAllWarnings true
	warningsAsErrors true
	''');
	return false;
	}
	return true;
	}

	/// Validates whether the given [example]'s gradle content is configured to
	/// build its plugin target with javac lints enabled and treated as errors,
	/// if the enclosing package is a plugin.
	///
	/// This can only be called on example packages. (Plugin packages should not
	/// be configured this way, since it would affect clients.)
	///
	/// If [example]'s enclosing package is not a plugin package, this just
	/// returns true.
	bool _validateJavacLintConfig(
	RepositoryPackage example, List<String> gradleLines) {
	final RepositoryPackage enclosingPackage = example.getEnclosingPackage()!;
	if (!pluginSupportsPlatform(platformAndroid, enclosingPackage,
	requiredMode: PlatformSupport.inline)) {
	return true;
	}
	final String enclosingPackageName = enclosingPackage.directory.basename;

	// The check here is intentionally somewhat loose, to allow for the
	// possibility of variations (e.g., not using Xlint:all in some cases, or
	// passing other arguments).
	if (!(gradleLines.any((String line) =>
	line.contains('project(":$enclosingPackageName")')) &&
	gradleLines.any((String line) =>
	line.contains('options.compilerArgs') &&
	line.contains('-Xlint') &&
	line.contains('-Werror')))) {
	printError('The example '
	'"${getRelativePosixPath(example.directory, from: enclosingPackage.directory)}" '
	'is not configured to treat javac lints and warnings as errors. '
	'Please add the following to its build.gradle:');
	print('''
	gradle.projectsEvaluated {
	project(":$enclosingPackageName") {
	tasks.withType(JavaCompile) {
	options.compilerArgs << "-Xlint:all" << "-Werror"
	}
	}
	}
	''');
	return false;
	}
	return true;
	}

	/// Validates whether the given [example] has its Kotlin version set to at
	/// least a minimum value, if it is set at all.
	bool _validateKotlinVersion(
	RepositoryPackage example, List<String> gradleLines) {
	final RegExp kotlinVersionRegex =
	RegExp(r"ext\.kotlin_version\s=\s'([\d.]+)'");
	RegExpMatch? match;
	if (gradleLines.any((String line) {
	match = kotlinVersionRegex.firstMatch(line);
	return match != null;
	})) {
	final Version version = Version.parse(match!.group(1)!);
	if (version < minKotlinVersion) {
	printError('build.gradle sets "ext.kotlin_version" to "$version". The '
	'minimum Kotlin version that can be specified is '
	'$minKotlinVersion, for compatibility with modern dependencies.');
	return false;
	}
	}
	return true;
	}
	}