pkgs/native_assets_cli/lib/src/model/build_config.dart - native - Git at Google

 // Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
 // for details. 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:convert';

 import 'package:cli_config/cli_config.dart';
 import 'package:collection/collection.dart';
 import 'package:crypto/crypto.dart';
 import 'package:pub_semver/pub_semver.dart';

 import '../utils/map.dart';
 import '../utils/yaml.dart';
 import 'ios_sdk.dart';
 import 'link_mode_preference.dart';
 import 'metadata.dart';
 import 'target.dart';

 class BuildConfig {
   /// The folder in which all output and intermediate artifacts should be
   /// placed.
   Uri get outDir => _outDir;
   late final Uri _outDir;

   /// The root of the package the native assets are built for.
   ///
   /// Often a package's native assets are built because a package is a
   /// dependency of another. For this it is convenient to know the packageRoot.
   Uri get packageRoot => _packageRoot;
   late final Uri _packageRoot;

   /// The target that is being compiled for.
   Target get target => _target;
   late final Target _target;

   /// When compiling for iOS, whether to target device or simulator.
   ///
   /// Required when [target.os] equals [OS.iOS].
   IOSSdk? get targetIOSSdk => _targetIOSSdk;
   late final IOSSdk? _targetIOSSdk;

   /// When compiling for Android, the API version to target.
   ///
   /// Required when [target.os] equals [OS.android].
   int? get targetAndroidNdkApi => _targetAndroidNdkApi;
   late final int? _targetAndroidNdkApi;

   /// Preferred linkMode method for library.
   LinkModePreference get linkModePreference => _linkModePreference;
   late final LinkModePreference _linkModePreference;

   /// Metadata from direct dependencies.
   ///
   /// The key in the map is the package name of the dependency.
   ///
   /// The key in the nested map is the key for the metadata from the dependency.
   Map<String, Metadata>? get dependencyMetadata => _dependencyMetadata;
   late final Map<String, Metadata>? _dependencyMetadata;

   /// The configuration for invoking the C compiler.
   CCompilerConfig get cCompiler => _cCompiler;
   late final CCompilerConfig _cCompiler;

   /// The underlying config.
   ///
   /// Can be used for easier access to values on [dependencyMetadata].
   Config get config => _config;
   late final Config _config;

   factory BuildConfig({
     required Uri outDir,
     required Uri packageRoot,
     required Target target,
     IOSSdk? targetIOSSdk,
     int? targetAndroidNdkApi,
     CCompilerConfig? cCompiler,
     required LinkModePreference linkModePreference,
     Map<String, Metadata>? dependencyMetadata,
   }) {
     final nonValidated = BuildConfig._()
       .._outDir = outDir
       .._packageRoot = packageRoot
       .._target = target
       .._targetIOSSdk = targetIOSSdk
       .._targetAndroidNdkApi = targetAndroidNdkApi
       .._cCompiler = cCompiler ?? CCompilerConfig()
       .._linkModePreference = linkModePreference
       .._dependencyMetadata = dependencyMetadata;
     final parsedConfigFile = nonValidated.toYaml();
     final config = Config(fileParsed: parsedConfigFile);
     return BuildConfig.fromConfig(config);
   }

   /// Constructs a checksum for a [BuildConfig] based on the fields
   /// of a buildconfig that influence the build.
   ///
   /// This can be used for an [outDir].
   ///
   /// In particular, it only takes the package name from [packageRoot],
   /// so that the hash is equal across checkouts and ignores [outDir] itself.
   static String checksum({
     required Uri packageRoot,
     required Target target,
     IOSSdk? targetIOSSdk,
     int? targetAndroidNdkApi,
     CCompilerConfig? cCompiler,
     required LinkModePreference linkModePreference,
     Map<String, Metadata>? dependencyMetadata,
   }) {
     final packageName = packageRoot.pathSegments.lastWhere((e) => e.isNotEmpty);
     final input = [
       packageName,
       target.toString(),
       targetIOSSdk.toString(),
       targetAndroidNdkApi.toString(),
       linkModePreference.toString(),
       cCompiler?.ar.toString(),
       cCompiler?.cc.toString(),
       cCompiler?.envScript.toString(),
       cCompiler?.envScriptArgs.toString(),
       cCompiler?.ld.toString(),
       if (dependencyMetadata != null)
         for (final entry in dependencyMetadata.entries) ...[
           entry.key,
           json.encode(entry.value.toYaml()),
         ]
     ].join('###');
     final sha256String = sha256.convert(utf8.encode(input)).toString();
     // 256 bit hashes lead to 64 hex character strings.
     // To avoid overflowing file paths limits, only use 32.
     // Using 16 hex characters would also be unlikely to have collisions.
     const nameLength = 32;
     return sha256String.substring(0, nameLength);
   }

   BuildConfig._();

   /// The version of [BuildConfig].
   ///
   /// This class is used in the protocol between the Dart and Flutter SDKs
   /// and packages through `build.dart` invocations.
   ///
   /// If we ever were to make breaking changes, it would be useful to give
   /// proper error messages rather than just fail to parse the YAML
   /// representation in the protocol.
   static Version version = Version(1, 0, 0);

   factory BuildConfig.fromConfig(Config config) {
     final result = BuildConfig._().._cCompiler = CCompilerConfig._();
     final configExceptions = <Object>[];
     for (final f in result._readFieldsFromConfig()) {
       try {
         f(config);
       } on FormatException catch (e, st) {
         configExceptions.add(e);
         configExceptions.add(st);
       }
     }

     if (configExceptions.isNotEmpty) {
       throw FormatException('Configuration is not in the right format. '
           'FormatExceptions: $configExceptions');
     }

     return result;
   }

   /// Constructs a config by parsing CLI arguments and loading the config file.
   ///
   /// The [args] must be commandline arguments.
   ///
   /// If provided, [environment] must be a map containing environment variables.
   /// If not provided, [environment] defaults to [Platform.environment].
   ///
   /// If provided, [workingDirectory] is used to resolves paths inside
   /// [environment].
   /// If not provided, [workingDirectory] defaults to [Directory.current].
   ///
   /// This async constructor is intended to be used directly in CLI files.
   static Future<BuildConfig> fromArgs(
     List<String> args, {
     Map<String, String>? environment,
     Uri? workingDirectory,
   }) async {
     final config = await Config.fromArgs(
       args: args,
       environment: environment,
       workingDirectory: workingDirectory,
     );
     return BuildConfig.fromConfig(config);
   }

   static const outDirConfigKey = 'out_dir';
   static const packageRootConfigKey = 'package_root';
   static const dependencyMetadataConfigKey = 'dependency_metadata';
   static const _versionKey = 'version';
   static const targetAndroidNdkApiConfigKey = 'target_android_ndk_api';

   List<void Function(Config)> _readFieldsFromConfig() {
     var targetSet = false;
     var ccSet = false;
     return [
       (config) {
         final configVersion = Version.parse(config.string('version'));
         if (configVersion.major > version.major) {
           throw FormatException(
             'The config version $configVersion is newer than this '
             'package:native_assets_cli config version $version, '
             'please update native_assets_cli.',
           );
         }
         if (configVersion.major < version.major) {
           throw FormatException(
             'The config version $configVersion is newer than this '
             'package:native_assets_cli config version $version, '
             'please update the Dart or Flutter SDK.',
           );
         }
       },
       (config) => _config = config,
       (config) => _outDir = config.path(outDirConfigKey, mustExist: true),
       (config) =>
           _packageRoot = config.path(packageRootConfigKey, mustExist: true),
       (config) {
         _target = Target.fromString(
           config.string(
             Target.configKey,
             validValues: Target.values.map((e) => '$e'),
           ),
         );
         targetSet = true;
       },
       (config) => _targetIOSSdk = (targetSet && _target.os == OS.iOS)
           ? IOSSdk.fromString(
               config.string(
                 IOSSdk.configKey,
                 validValues: IOSSdk.values.map((e) => '$e'),
               ),
             )
           : null,
       (config) => _targetAndroidNdkApi = (targetSet && _target.os == OS.android)
           ? config.int(targetAndroidNdkApiConfigKey)
           : null,
       (config) => cCompiler._ar =
           config.optionalPath(CCompilerConfig.arConfigKeyFull, mustExist: true),
       (config) {
         cCompiler._cc = config.optionalPath(CCompilerConfig.ccConfigKeyFull,
             mustExist: true);
         ccSet = true;
       },
       (config) => cCompiler._ld =
           config.optionalPath(CCompilerConfig.ldConfigKeyFull, mustExist: true),
       (config) => cCompiler._envScript = (ccSet &&
               cCompiler.cc != null &&
               cCompiler.cc!.toFilePath().endsWith('cl.exe'))
           ? config.path(CCompilerConfig.envScriptConfigKeyFull, mustExist: true)
           : null,
       (config) => cCompiler._envScriptArgs = config.optionalStringList(
             CCompilerConfig.envScriptArgsConfigKeyFull,
             splitEnvironmentPattern: ' ',
           ),
       (config) => _linkModePreference = LinkModePreference.fromString(
             config.string(
               LinkModePreference.configKey,
               validValues: LinkModePreference.values.map((e) => '$e'),
             ),
           ),
       (config) =>
           _dependencyMetadata = _readDependencyMetadataFromConfig(config)
     ];
   }

   Map<String, Metadata>? _readDependencyMetadataFromConfig(Config config) {
     final fileValue =
         config.valueOf<Map<Object?, Object?>?>(dependencyMetadataConfigKey);
     if (fileValue == null) {
       return null;
     }
     final result = <String, Metadata>{};
     for (final entry in fileValue.entries) {
       final packageName = entry.key;
       final defines = entry.value;
       if (defines is! Map) {
         throw FormatException("Unexpected value '$defines' for key "
             "'$dependencyMetadataConfigKey.$packageName' in config file. "
             'Expected a Map.');
       }
       final packageResult = <String, Object>{};
       for (final entry2 in defines.entries) {
         final key = entry2.key;
         assert(key is String);
         final value = entry2.value;
         assert(value != null);
         packageResult[key as String] = value as Object;
       }
       result[packageName as String] = Metadata(packageResult.sortOnKey());
     }
     return result.sortOnKey();
   }

   Map<String, Object> toYaml() {
     final cCompilerYaml = _cCompiler.toYaml();

     return {
       outDirConfigKey: _outDir.toFilePath(),
       packageRootConfigKey: _packageRoot.toFilePath(),
       Target.configKey: _target.toString(),
       if (_targetIOSSdk != null) IOSSdk.configKey: _targetIOSSdk.toString(),
       if (_targetAndroidNdkApi != null)
         targetAndroidNdkApiConfigKey: _targetAndroidNdkApi!,
       if (cCompilerYaml.isNotEmpty) CCompilerConfig.configKey: cCompilerYaml,
       LinkModePreference.configKey: _linkModePreference.toString(),
       if (_dependencyMetadata != null)
         dependencyMetadataConfigKey: {
           for (final entry in _dependencyMetadata!.entries)
             entry.key: entry.value.toYaml(),
         },
       _versionKey: version.toString(),
     }.sortOnKey();
   }

   String toYamlString() => yamlEncode(toYaml());

   @override
   bool operator ==(Object other) {
     if (other is! BuildConfig) {
       return false;
     }
     if (other._outDir != _outDir) return false;
     if (other._packageRoot != _packageRoot) return false;
     if (other._target != _target) return false;
     if (other._targetIOSSdk != _targetIOSSdk) return false;
     if (other._targetAndroidNdkApi != _targetAndroidNdkApi) return false;
     if (other._cCompiler != _cCompiler) return false;
     if (other._linkModePreference != _linkModePreference) return false;
     if (!DeepCollectionEquality()
         .equals(other._dependencyMetadata, _dependencyMetadata)) return false;
     return true;
   }

   @override
   int get hashCode => Object.hash(
         _outDir,
         _packageRoot,
         _target,
         _targetIOSSdk,
         _targetAndroidNdkApi,
         _cCompiler,
         _linkModePreference,
         DeepCollectionEquality().hash(_dependencyMetadata),
       );

   @override
   String toString() => 'BuildConfig(${toYaml()})';
 }

 class CCompilerConfig {
   /// Path to a C compiler.
   Uri? get cc => _cc;
   late final Uri? _cc;

   /// Path to a native linker.
   Uri? get ld => _ld;
   late final Uri? _ld;

   /// Path to a native archiver.
   Uri? get ar => _ar;
   late final Uri? _ar;

   /// Path to script that sets environment variables for [cc], [ld], and [ar].
   Uri? get envScript => _envScript;
   late final Uri? _envScript;

   /// Arguments for [envScript].
   List<String>? get envScriptArgs => _envScriptArgs;
   late final List<String>? _envScriptArgs;

   factory CCompilerConfig({
     Uri? ar,
     Uri? cc,
     Uri? ld,
     Uri? envScript,
     List<String>? envScriptArgs,
   }) =>
       CCompilerConfig._()
         .._ar = ar
         .._cc = cc
         .._ld = ld
         .._envScript = envScript
         .._envScriptArgs = envScriptArgs;

   CCompilerConfig._();

   static const configKey = 'c_compiler';
   static const arConfigKey = 'ar';
   static const arConfigKeyFull = '$configKey.$arConfigKey';
   static const ccConfigKey = 'cc';
   static const ccConfigKeyFull = '$configKey.$ccConfigKey';
   static const ldConfigKey = 'ld';
   static const ldConfigKeyFull = '$configKey.$ldConfigKey';
   static const envScriptConfigKey = 'env_script';
   static const envScriptConfigKeyFull = '$configKey.$envScriptConfigKey';
   static const envScriptArgsConfigKey = 'env_script_arguments';
   static const envScriptArgsConfigKeyFull =
       '$configKey.$envScriptArgsConfigKey';

   Map<String, Object> toYaml() => {
         if (_ar != null) arConfigKey: _ar!.toFilePath(),
         if (_cc != null) ccConfigKey: _cc!.toFilePath(),
         if (_ld != null) ldConfigKey: _ld!.toFilePath(),
         if (_envScript != null) envScriptConfigKey: _envScript!.toFilePath(),
         if (_envScriptArgs != null) envScriptArgsConfigKey: _envScriptArgs!,
       }.sortOnKey();

   @override
   bool operator ==(Object other) {
     if (other is! CCompilerConfig) {
       return false;
     }
     if (other._ar != _ar) return false;
     if (other._cc != _cc) return false;
     if (other._ld != _ld) return false;
     if (other.envScript != envScript) return false;
     if (!ListEquality<String>().equals(other.envScriptArgs, envScriptArgs)) {
       return false;
     }
     return true;
   }

   @override
   int get hashCode => Object.hash(
         _ar,
         _cc,
         _ld,
         _envScript,
         ListEquality<String>().hash(envScriptArgs),
       );
 }
	// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file
	// for details. 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:convert';

	import 'package:cli_config/cli_config.dart';
	import 'package:collection/collection.dart';
	import 'package:crypto/crypto.dart';
	import 'package:pub_semver/pub_semver.dart';

	import '../utils/map.dart';
	import '../utils/yaml.dart';
	import 'ios_sdk.dart';
	import 'link_mode_preference.dart';
	import 'metadata.dart';
	import 'target.dart';

	class BuildConfig {
	/// The folder in which all output and intermediate artifacts should be
	/// placed.
	Uri get outDir => _outDir;
	late final Uri _outDir;

	/// The root of the package the native assets are built for.
	///
	/// Often a package's native assets are built because a package is a
	/// dependency of another. For this it is convenient to know the packageRoot.
	Uri get packageRoot => _packageRoot;
	late final Uri _packageRoot;

	/// The target that is being compiled for.
	Target get target => _target;
	late final Target _target;

	/// When compiling for iOS, whether to target device or simulator.
	///
	/// Required when [target.os] equals [OS.iOS].
	IOSSdk? get targetIOSSdk => _targetIOSSdk;
	late final IOSSdk? _targetIOSSdk;

	/// When compiling for Android, the API version to target.
	///
	/// Required when [target.os] equals [OS.android].
	int? get targetAndroidNdkApi => _targetAndroidNdkApi;
	late final int? _targetAndroidNdkApi;

	/// Preferred linkMode method for library.
	LinkModePreference get linkModePreference => _linkModePreference;
	late final LinkModePreference _linkModePreference;

	/// Metadata from direct dependencies.
	///
	/// The key in the map is the package name of the dependency.
	///
	/// The key in the nested map is the key for the metadata from the dependency.
	Map<String, Metadata>? get dependencyMetadata => _dependencyMetadata;
	late final Map<String, Metadata>? _dependencyMetadata;

	/// The configuration for invoking the C compiler.
	CCompilerConfig get cCompiler => _cCompiler;
	late final CCompilerConfig _cCompiler;

	/// The underlying config.
	///
	/// Can be used for easier access to values on [dependencyMetadata].
	Config get config => _config;
	late final Config _config;

	factory BuildConfig({
	required Uri outDir,
	required Uri packageRoot,
	required Target target,
	IOSSdk? targetIOSSdk,
	int? targetAndroidNdkApi,
	CCompilerConfig? cCompiler,
	required LinkModePreference linkModePreference,
	Map<String, Metadata>? dependencyMetadata,
	}) {
	final nonValidated = BuildConfig._()
	.._outDir = outDir
	.._packageRoot = packageRoot
	.._target = target
	.._targetIOSSdk = targetIOSSdk
	.._targetAndroidNdkApi = targetAndroidNdkApi
	.._cCompiler = cCompiler ?? CCompilerConfig()
	.._linkModePreference = linkModePreference
	.._dependencyMetadata = dependencyMetadata;
	final parsedConfigFile = nonValidated.toYaml();
	final config = Config(fileParsed: parsedConfigFile);
	return BuildConfig.fromConfig(config);
	}

	/// Constructs a checksum for a [BuildConfig] based on the fields
	/// of a buildconfig that influence the build.
	///
	/// This can be used for an [outDir].
	///
	/// In particular, it only takes the package name from [packageRoot],
	/// so that the hash is equal across checkouts and ignores [outDir] itself.
	static String checksum({
	required Uri packageRoot,
	required Target target,
	IOSSdk? targetIOSSdk,
	int? targetAndroidNdkApi,
	CCompilerConfig? cCompiler,
	required LinkModePreference linkModePreference,
	Map<String, Metadata>? dependencyMetadata,
	}) {
	final packageName = packageRoot.pathSegments.lastWhere((e) => e.isNotEmpty);
	final input = [
	packageName,
	target.toString(),
	targetIOSSdk.toString(),
	targetAndroidNdkApi.toString(),
	linkModePreference.toString(),
	cCompiler?.ar.toString(),
	cCompiler?.cc.toString(),
	cCompiler?.envScript.toString(),
	cCompiler?.envScriptArgs.toString(),
	cCompiler?.ld.toString(),
	if (dependencyMetadata != null)
	for (final entry in dependencyMetadata.entries) ...[
	entry.key,
	json.encode(entry.value.toYaml()),
	]
	].join('###');
	final sha256String = sha256.convert(utf8.encode(input)).toString();
	// 256 bit hashes lead to 64 hex character strings.
	// To avoid overflowing file paths limits, only use 32.
	// Using 16 hex characters would also be unlikely to have collisions.
	const nameLength = 32;
	return sha256String.substring(0, nameLength);
	}

	BuildConfig._();

	/// The version of [BuildConfig].
	///
	/// This class is used in the protocol between the Dart and Flutter SDKs
	/// and packages through `build.dart` invocations.
	///
	/// If we ever were to make breaking changes, it would be useful to give
	/// proper error messages rather than just fail to parse the YAML
	/// representation in the protocol.
	static Version version = Version(1, 0, 0);

	factory BuildConfig.fromConfig(Config config) {
	final result = BuildConfig._().._cCompiler = CCompilerConfig._();
	final configExceptions = <Object>[];
	for (final f in result._readFieldsFromConfig()) {
	try {
	f(config);
	} on FormatException catch (e, st) {
	configExceptions.add(e);
	configExceptions.add(st);
	}
	}

	if (configExceptions.isNotEmpty) {
	throw FormatException('Configuration is not in the right format. '
	'FormatExceptions: $configExceptions');
	}

	return result;
	}

	/// Constructs a config by parsing CLI arguments and loading the config file.
	///
	/// The [args] must be commandline arguments.
	///
	/// If provided, [environment] must be a map containing environment variables.
	/// If not provided, [environment] defaults to [Platform.environment].
	///
	/// If provided, [workingDirectory] is used to resolves paths inside
	/// [environment].
	/// If not provided, [workingDirectory] defaults to [Directory.current].
	///
	/// This async constructor is intended to be used directly in CLI files.
	static Future<BuildConfig> fromArgs(
	List<String> args, {
	Map<String, String>? environment,
	Uri? workingDirectory,
	}) async {
	final config = await Config.fromArgs(
	args: args,
	environment: environment,
	workingDirectory: workingDirectory,
	);
	return BuildConfig.fromConfig(config);
	}

	static const outDirConfigKey = 'out_dir';
	static const packageRootConfigKey = 'package_root';
	static const dependencyMetadataConfigKey = 'dependency_metadata';
	static const _versionKey = 'version';
	static const targetAndroidNdkApiConfigKey = 'target_android_ndk_api';

	List<void Function(Config)> _readFieldsFromConfig() {
	var targetSet = false;
	var ccSet = false;
	return [
	(config) {
	final configVersion = Version.parse(config.string('version'));
	if (configVersion.major > version.major) {
	throw FormatException(
	'The config version $configVersion is newer than this '
	'package:native_assets_cli config version $version, '
	'please update native_assets_cli.',
	);
	}
	if (configVersion.major < version.major) {
	throw FormatException(
	'The config version $configVersion is newer than this '
	'package:native_assets_cli config version $version, '
	'please update the Dart or Flutter SDK.',
	);
	}
	},
	(config) => _config = config,
	(config) => _outDir = config.path(outDirConfigKey, mustExist: true),
	(config) =>
	_packageRoot = config.path(packageRootConfigKey, mustExist: true),
	(config) {
	_target = Target.fromString(
	config.string(
	Target.configKey,
	validValues: Target.values.map((e) => '$e'),
	),
	);
	targetSet = true;
	},
	(config) => _targetIOSSdk = (targetSet && _target.os == OS.iOS)
	? IOSSdk.fromString(
	config.string(
	IOSSdk.configKey,
	validValues: IOSSdk.values.map((e) => '$e'),
	),
	)
	: null,
	(config) => _targetAndroidNdkApi = (targetSet && _target.os == OS.android)
	? config.int(targetAndroidNdkApiConfigKey)
	: null,
	(config) => cCompiler._ar =
	config.optionalPath(CCompilerConfig.arConfigKeyFull, mustExist: true),
	(config) {
	cCompiler._cc = config.optionalPath(CCompilerConfig.ccConfigKeyFull,
	mustExist: true);
	ccSet = true;
	},
	(config) => cCompiler._ld =
	config.optionalPath(CCompilerConfig.ldConfigKeyFull, mustExist: true),
	(config) => cCompiler._envScript = (ccSet &&
	cCompiler.cc != null &&
	cCompiler.cc!.toFilePath().endsWith('cl.exe'))
	? config.path(CCompilerConfig.envScriptConfigKeyFull, mustExist: true)
	: null,
	(config) => cCompiler._envScriptArgs = config.optionalStringList(
	CCompilerConfig.envScriptArgsConfigKeyFull,
	splitEnvironmentPattern: ' ',
	),
	(config) => _linkModePreference = LinkModePreference.fromString(
	config.string(
	LinkModePreference.configKey,
	validValues: LinkModePreference.values.map((e) => '$e'),
	),
	),
	(config) =>
	_dependencyMetadata = _readDependencyMetadataFromConfig(config)
	];
	}

	Map<String, Metadata>? _readDependencyMetadataFromConfig(Config config) {
	final fileValue =
	config.valueOf<Map<Object?, Object?>?>(dependencyMetadataConfigKey);
	if (fileValue == null) {
	return null;
	}
	final result = <String, Metadata>{};
	for (final entry in fileValue.entries) {
	final packageName = entry.key;
	final defines = entry.value;
	if (defines is! Map) {
	throw FormatException("Unexpected value '$defines' for key "
	"'$dependencyMetadataConfigKey.$packageName' in config file. "
	'Expected a Map.');
	}
	final packageResult = <String, Object>{};
	for (final entry2 in defines.entries) {
	final key = entry2.key;
	assert(key is String);
	final value = entry2.value;
	assert(value != null);
	packageResult[key as String] = value as Object;
	}
	result[packageName as String] = Metadata(packageResult.sortOnKey());
	}
	return result.sortOnKey();
	}

	Map<String, Object> toYaml() {
	final cCompilerYaml = _cCompiler.toYaml();

	return {
	outDirConfigKey: _outDir.toFilePath(),
	packageRootConfigKey: _packageRoot.toFilePath(),
	Target.configKey: _target.toString(),
	if (_targetIOSSdk != null) IOSSdk.configKey: _targetIOSSdk.toString(),
	if (_targetAndroidNdkApi != null)
	targetAndroidNdkApiConfigKey: _targetAndroidNdkApi!,
	if (cCompilerYaml.isNotEmpty) CCompilerConfig.configKey: cCompilerYaml,
	LinkModePreference.configKey: _linkModePreference.toString(),
	if (_dependencyMetadata != null)
	dependencyMetadataConfigKey: {
	for (final entry in _dependencyMetadata!.entries)
	entry.key: entry.value.toYaml(),
	},
	_versionKey: version.toString(),
	}.sortOnKey();
	}

	String toYamlString() => yamlEncode(toYaml());

	@override
	bool operator ==(Object other) {
	if (other is! BuildConfig) {
	return false;
	}
	if (other._outDir != _outDir) return false;
	if (other._packageRoot != _packageRoot) return false;
	if (other._target != _target) return false;
	if (other._targetIOSSdk != _targetIOSSdk) return false;
	if (other._targetAndroidNdkApi != _targetAndroidNdkApi) return false;
	if (other._cCompiler != _cCompiler) return false;
	if (other._linkModePreference != _linkModePreference) return false;
	if (!DeepCollectionEquality()
	.equals(other._dependencyMetadata, _dependencyMetadata)) return false;
	return true;
	}

	@override
	int get hashCode => Object.hash(
	_outDir,
	_packageRoot,
	_target,
	_targetIOSSdk,
	_targetAndroidNdkApi,
	_cCompiler,
	_linkModePreference,
	DeepCollectionEquality().hash(_dependencyMetadata),
	);

	@override
	String toString() => 'BuildConfig(${toYaml()})';
	}

	class CCompilerConfig {
	/// Path to a C compiler.
	Uri? get cc => _cc;
	late final Uri? _cc;

	/// Path to a native linker.
	Uri? get ld => _ld;
	late final Uri? _ld;

	/// Path to a native archiver.
	Uri? get ar => _ar;
	late final Uri? _ar;

	/// Path to script that sets environment variables for [cc], [ld], and [ar].
	Uri? get envScript => _envScript;
	late final Uri? _envScript;

	/// Arguments for [envScript].
	List<String>? get envScriptArgs => _envScriptArgs;
	late final List<String>? _envScriptArgs;

	factory CCompilerConfig({
	Uri? ar,
	Uri? cc,
	Uri? ld,
	Uri? envScript,
	List<String>? envScriptArgs,
	}) =>
	CCompilerConfig._()
	.._ar = ar
	.._cc = cc
	.._ld = ld
	.._envScript = envScript
	.._envScriptArgs = envScriptArgs;

	CCompilerConfig._();

	static const configKey = 'c_compiler';
	static const arConfigKey = 'ar';
	static const arConfigKeyFull = '$configKey.$arConfigKey';
	static const ccConfigKey = 'cc';
	static const ccConfigKeyFull = '$configKey.$ccConfigKey';
	static const ldConfigKey = 'ld';
	static const ldConfigKeyFull = '$configKey.$ldConfigKey';
	static const envScriptConfigKey = 'env_script';
	static const envScriptConfigKeyFull = '$configKey.$envScriptConfigKey';
	static const envScriptArgsConfigKey = 'env_script_arguments';
	static const envScriptArgsConfigKeyFull =
	'$configKey.$envScriptArgsConfigKey';

	Map<String, Object> toYaml() => {
	if (_ar != null) arConfigKey: _ar!.toFilePath(),
	if (_cc != null) ccConfigKey: _cc!.toFilePath(),
	if (_ld != null) ldConfigKey: _ld!.toFilePath(),
	if (_envScript != null) envScriptConfigKey: _envScript!.toFilePath(),
	if (_envScriptArgs != null) envScriptArgsConfigKey: _envScriptArgs!,
	}.sortOnKey();

	@override
	bool operator ==(Object other) {
	if (other is! CCompilerConfig) {
	return false;
	}
	if (other._ar != _ar) return false;
	if (other._cc != _cc) return false;
	if (other._ld != _ld) return false;
	if (other.envScript != envScript) return false;
	if (!ListEquality<String>().equals(other.envScriptArgs, envScriptArgs)) {
	return false;
	}
	return true;
	}

	@override
	int get hashCode => Object.hash(
	_ar,
	_cc,
	_ld,
	_envScript,
	ListEquality<String>().hash(envScriptArgs),
	);
	}