packages/flutter_tools/lib/src/commands/assemble.dart - mirrors/flutter - Git at Google

 // 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 'package:args/args.dart';
 import 'package:meta/meta.dart';

 import '../artifacts.dart';
 import '../base/common.dart';
 import '../base/file_system.dart';
 import '../build_info.dart';
 import '../build_system/build_system.dart';
 import '../build_system/depfile.dart';
 import '../build_system/targets/android.dart';
 import '../build_system/targets/assets.dart';
 import '../build_system/targets/common.dart';
 import '../build_system/targets/deferred_components.dart';
 import '../build_system/targets/ios.dart';
 import '../build_system/targets/linux.dart';
 import '../build_system/targets/macos.dart';
 import '../build_system/targets/windows.dart';
 import '../cache.dart';
 import '../convert.dart';
 import '../globals.dart' as globals;
 import '../project.dart';
 import '../reporting/reporting.dart';
 import '../runner/flutter_command.dart';

 /// All currently implemented targets.
 List<Target> _kDefaultTargets = <Target>[
   // Shared targets
   const CopyAssets(),
   const KernelSnapshot(),
   const AotElfProfile(TargetPlatform.android_arm),
   const AotElfRelease(TargetPlatform.android_arm),
   const AotAssemblyProfile(),
   const AotAssemblyRelease(),
   // macOS targets
   const DebugMacOSFramework(),
   const DebugMacOSBundleFlutterAssets(),
   const ProfileMacOSBundleFlutterAssets(),
   const ReleaseMacOSBundleFlutterAssets(),
   // Linux targets
   const DebugBundleLinuxAssets(TargetPlatform.linux_x64),
   const DebugBundleLinuxAssets(TargetPlatform.linux_arm64),
   const ProfileBundleLinuxAssets(TargetPlatform.linux_x64),
   const ProfileBundleLinuxAssets(TargetPlatform.linux_arm64),
   const ReleaseBundleLinuxAssets(TargetPlatform.linux_x64),
   const ReleaseBundleLinuxAssets(TargetPlatform.linux_arm64),
   const ReleaseAndroidApplication(),
   // This is a one-off rule for bundle and aot compat.
   const CopyFlutterBundle(),
   // Android targets,
   const DebugAndroidApplication(),
   const ProfileAndroidApplication(),
   // Android ABI specific AOT rules.
   androidArmProfileBundle,
   androidArm64ProfileBundle,
   androidx64ProfileBundle,
   androidArmReleaseBundle,
   androidArm64ReleaseBundle,
   androidx64ReleaseBundle,
   // Deferred component enabled AOT rules
   androidArmProfileDeferredComponentsBundle,
   androidArm64ProfileDeferredComponentsBundle,
   androidx64ProfileDeferredComponentsBundle,
   androidArmReleaseDeferredComponentsBundle,
   androidArm64ReleaseDeferredComponentsBundle,
   androidx64ReleaseDeferredComponentsBundle,
   // iOS targets
   const DebugIosApplicationBundle(),
   const ProfileIosApplicationBundle(),
   const ReleaseIosApplicationBundle(),
   // Windows targets
   const UnpackWindows(),
   const DebugBundleWindowsAssets(),
   const ProfileBundleWindowsAssets(),
   const ReleaseBundleWindowsAssets(),
 ];

 /// Assemble provides a low level API to interact with the flutter tool build
 /// system.
 class AssembleCommand extends FlutterCommand {
   AssembleCommand({ bool verboseHelp = false, required BuildSystem buildSystem })
     : _buildSystem = buildSystem {
     argParser.addMultiOption(
       'define',
       abbr: 'd',
       valueHelp: 'target=key=value',
       help: 'Allows passing configuration to a target, as in "--define=target=key=value".',
     );
     argParser.addOption(
       'performance-measurement-file',
       help: 'Output individual target performance to a JSON file.'
     );
     argParser.addMultiOption(
       'input',
       abbr: 'i',
       help: 'Allows passing additional inputs with "--input=key=value". Unlike '
       'defines, additional inputs do not generate a new configuration; instead '
       'they are treated as dependencies of the targets that use them.'
     );
     argParser.addOption('depfile',
       help: 'A file path where a depfile will be written. '
             'This contains all build inputs and outputs in a Make-style syntax.'
     );
     argParser.addOption('build-inputs', help: 'A file path where a newline-separated '
         'file containing all inputs used will be written after a build. '
         'This file is not included as a build input or output. This file is not '
         'written if the build fails for any reason.');
     argParser.addOption('build-outputs', help: 'A file path where a newline-separated '
         'file containing all outputs created will be written after a build. '
         'This file is not included as a build input or output. This file is not '
         'written if the build fails for any reason.');
     argParser.addOption('output', abbr: 'o', help: 'A directory where output '
         'files will be written. Must be either absolute or relative from the '
         'root of the current Flutter project.',
     );
     usesExtraDartFlagOptions(verboseHelp: verboseHelp);
     usesDartDefineOption();
     argParser.addOption(
       'resource-pool-size',
       help: 'The maximum number of concurrent tasks the build system will run.',
     );
   }

   final BuildSystem _buildSystem;

   @override
   String get description => 'Assemble and build Flutter resources.';

   @override
   String get name => 'assemble';

   @override
   String get category => FlutterCommandCategory.project;

   @override
   Future<CustomDimensions> get usageValues async {
     final FlutterProject flutterProject = FlutterProject.current();
     try {
       return CustomDimensions(
         commandBuildBundleTargetPlatform: _environment.defines[kTargetPlatform],
         commandBuildBundleIsModule: flutterProject.isModule,
       );
     } on Exception {
       // We've failed to send usage.
     }
     return const CustomDimensions();
   }

   @override
   Future<Set<DevelopmentArtifact>> get requiredArtifacts async {
     final String? platform = _environment.defines[kTargetPlatform];
     if (platform == null) {
       return super.requiredArtifacts;
     }

     final TargetPlatform targetPlatform = getTargetPlatformForName(platform);
     final DevelopmentArtifact? artifact = artifactFromTargetPlatform(targetPlatform);
     if (artifact != null) {
       return <DevelopmentArtifact>{artifact};
     }
     return super.requiredArtifacts;
   }

   /// The target(s) we are building.
   List<Target> createTargets() {
     final ArgResults argumentResults = argResults!;
     if (argumentResults.rest.isEmpty) {
       throwToolExit('missing target name for flutter assemble.');
     }
     final String name = argumentResults.rest.first;
     final Map<String, Target> targetMap = <String, Target>{
       for (final Target target in _kDefaultTargets)
         target.name: target,
     };
     final List<Target> results = <Target>[
       for (final String targetName in argumentResults.rest)
         if (targetMap.containsKey(targetName))
           targetMap[targetName]!,
     ];
     if (results.isEmpty) {
       throwToolExit('No target named "$name" defined.');
     }
     return results;
   }

   bool isDeferredComponentsTargets() {
     for (final String targetName in argResults!.rest) {
       if (deferredComponentsTargets.contains(targetName)) {
         return true;
       }
     }
     return false;
   }

   bool isDebug() {
     for (final String targetName in argResults!.rest) {
       if (targetName.contains('debug')) {
         return true;
       }
     }
     return false;
   }

   late final Environment _environment = _createEnvironment();

   /// The environmental configuration for a build invocation.
   Environment _createEnvironment() {
     final FlutterProject flutterProject = FlutterProject.current();
     String? output = stringArg('output');
     if (output == null) {
       throwToolExit('--output directory is required for assemble.');
     }
     // If path is relative, make it absolute from flutter project.
     if (globals.fs.path.isRelative(output)) {
       output = globals.fs.path.join(flutterProject.directory.path, output);
     }
     final Artifacts artifacts = globals.artifacts!;
     final Environment result = Environment(
       outputDir: globals.fs.directory(output),
       buildDir: flutterProject.directory
           .childDirectory('.dart_tool')
           .childDirectory('flutter_build'),
       projectDir: flutterProject.directory,
       defines: _parseDefines(stringsArg('define')),
       inputs: _parseDefines(stringsArg('input')),
       cacheDir: globals.cache.getRoot(),
       flutterRootDir: globals.fs.directory(Cache.flutterRoot),
       artifacts: artifacts,
       fileSystem: globals.fs,
       logger: globals.logger,
       processManager: globals.processManager,
       usage: globals.flutterUsage,
       platform: globals.platform,
       engineVersion: artifacts.isLocalEngine
         ? null
         : globals.flutterVersion.engineRevision,
       generateDartPluginRegistry: true,
     );
     return result;
   }

   Map<String, String> _parseDefines(List<String> values) {
     final Map<String, String> results = <String, String>{};
     for (final String chunk in values) {
       final int indexEquals = chunk.indexOf('=');
       if (indexEquals == -1) {
         throwToolExit('Improperly formatted define flag: $chunk');
       }
       final String key = chunk.substring(0, indexEquals);
       final String value = chunk.substring(indexEquals + 1);
       results[key] = value;
     }
     final ArgResults argumentResults = argResults!;
     if (argumentResults.wasParsed(FlutterOptions.kExtraGenSnapshotOptions)) {
       results[kExtraGenSnapshotOptions] = (argumentResults[FlutterOptions.kExtraGenSnapshotOptions] as List<String>).join(',');
     }

     final Map<String, Object?> defineConfigJsonMap = extractDartDefineConfigJsonMap();
     final List<String> dartDefines = extractDartDefines(defineConfigJsonMap: defineConfigJsonMap);
     if (dartDefines.isNotEmpty){
       results[kDartDefines] = dartDefines.join(',');
     }

     results[kDeferredComponents] = 'false';
     if (FlutterProject.current().manifest.deferredComponents != null && isDeferredComponentsTargets() && !isDebug()) {
       results[kDeferredComponents] = 'true';
     }
     if (argumentResults.wasParsed(FlutterOptions.kExtraFrontEndOptions)) {
       results[kExtraFrontEndOptions] = (argumentResults[FlutterOptions.kExtraFrontEndOptions] as List<String>).join(',');
     }
     return results;
   }

   @override
   Future<FlutterCommandResult> runCommand() async {
     final List<Target> targets = createTargets();
     final List<Target> nonDeferredTargets = <Target>[];
     final List<Target> deferredTargets = <AndroidAotDeferredComponentsBundle>[];
     for (final Target target in targets) {
       if (deferredComponentsTargets.contains(target.name)) {
         deferredTargets.add(target);
       } else {
         nonDeferredTargets.add(target);
       }
     }
     Target? target;
     List<String> decodedDefines;
     try {
       decodedDefines = decodeDartDefines(_environment.defines, kDartDefines);
     } on FormatException {
       throwToolExit(
         'Error parsing assemble command: your generated configuration may be out of date. '
         "Try re-running 'flutter build ios' or the appropriate build command."
       );
     }
     if (FlutterProject.current().manifest.deferredComponents != null
         && decodedDefines.contains('validate-deferred-components=true')
         && deferredTargets.isNotEmpty
         && !isDebug()) {
       // Add deferred components validation target that require loading units.
       target = DeferredComponentsGenSnapshotValidatorTarget(
         deferredComponentsDependencies: deferredTargets.cast<AndroidAotDeferredComponentsBundle>(),
         nonDeferredComponentsDependencies: nonDeferredTargets,
         title: 'Deferred components gen_snapshot validation',
       );
     } else if (targets.length > 1) {
       target = CompositeTarget(targets);
     } else if (targets.isNotEmpty) {
       target = targets.single;
     }
     final ArgResults argumentResults = argResults!;
     final BuildResult result = await _buildSystem.build(
       target!,
       _environment,
       buildSystemConfig: BuildSystemConfig(
         resourcePoolSize: argumentResults.wasParsed('resource-pool-size')
           ? int.tryParse(stringArg('resource-pool-size')!)
           : null,
         ),
       );
     if (!result.success) {
       for (final ExceptionMeasurement measurement in result.exceptions.values) {
         if (measurement.fatal || globals.logger.isVerbose) {
           globals.printError('Target ${measurement.target} failed: ${measurement.exception}',
             stackTrace: globals.logger.isVerbose ? measurement.stackTrace : null,
           );
         }
       }
       throwToolExit('');
     }
     globals.printTrace('build succeeded.');

     if (argumentResults.wasParsed('build-inputs')) {
       writeListIfChanged(result.inputFiles, stringArg('build-inputs')!);
     }
     if (argumentResults.wasParsed('build-outputs')) {
       writeListIfChanged(result.outputFiles, stringArg('build-outputs')!);
     }
     if (argumentResults.wasParsed('performance-measurement-file')) {
       final File outFile = globals.fs.file(argumentResults['performance-measurement-file']);
       writePerformanceData(result.performance.values, outFile);
     }
     if (argumentResults.wasParsed('depfile')) {
       final File depfileFile = globals.fs.file(stringArg('depfile'));
       final Depfile depfile = Depfile(result.inputFiles, result.outputFiles);
       _environment.depFileService.writeToFile(depfile, globals.fs.file(depfileFile));
     }
     return FlutterCommandResult.success();
   }
 }

 @visibleForTesting
 void writeListIfChanged(List<File> files, String path) {
   final File file = globals.fs.file(path);
   final StringBuffer buffer = StringBuffer();
   // These files are already sorted.
   for (final File file in files) {
     buffer.writeln(file.path);
   }
   final String newContents = buffer.toString();
   if (!file.existsSync()) {
     file.writeAsStringSync(newContents);
   }
   final String currentContents = file.readAsStringSync();
   if (currentContents != newContents) {
     file.writeAsStringSync(newContents);
   }
 }

 /// Output performance measurement data in [outFile].
 @visibleForTesting
 void writePerformanceData(Iterable<PerformanceMeasurement> measurements, File outFile) {
   final Map<String, Object> jsonData = <String, Object>{
     'targets': <Object>[
       for (final PerformanceMeasurement measurement in measurements)
         <String, Object>{
           'name': measurement.analyticsName,
           'skipped': measurement.skipped,
           'succeeded': measurement.succeeded,
           'elapsedMilliseconds': measurement.elapsedMilliseconds,
         },
     ],
   };
   if (!outFile.parent.existsSync()) {
     outFile.parent.createSync(recursive: true);
   }
   outFile.writeAsStringSync(json.encode(jsonData));
 }
	// 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 'package:args/args.dart';
	import 'package:meta/meta.dart';

	import '../artifacts.dart';
	import '../base/common.dart';
	import '../base/file_system.dart';
	import '../build_info.dart';
	import '../build_system/build_system.dart';
	import '../build_system/depfile.dart';
	import '../build_system/targets/android.dart';
	import '../build_system/targets/assets.dart';
	import '../build_system/targets/common.dart';
	import '../build_system/targets/deferred_components.dart';
	import '../build_system/targets/ios.dart';
	import '../build_system/targets/linux.dart';
	import '../build_system/targets/macos.dart';
	import '../build_system/targets/windows.dart';
	import '../cache.dart';
	import '../convert.dart';
	import '../globals.dart' as globals;
	import '../project.dart';
	import '../reporting/reporting.dart';
	import '../runner/flutter_command.dart';

	/// All currently implemented targets.
	List<Target> _kDefaultTargets = <Target>[
	// Shared targets
	const CopyAssets(),
	const KernelSnapshot(),
	const AotElfProfile(TargetPlatform.android_arm),
	const AotElfRelease(TargetPlatform.android_arm),
	const AotAssemblyProfile(),
	const AotAssemblyRelease(),
	// macOS targets
	const DebugMacOSFramework(),
	const DebugMacOSBundleFlutterAssets(),
	const ProfileMacOSBundleFlutterAssets(),
	const ReleaseMacOSBundleFlutterAssets(),
	// Linux targets
	const DebugBundleLinuxAssets(TargetPlatform.linux_x64),
	const DebugBundleLinuxAssets(TargetPlatform.linux_arm64),
	const ProfileBundleLinuxAssets(TargetPlatform.linux_x64),
	const ProfileBundleLinuxAssets(TargetPlatform.linux_arm64),
	const ReleaseBundleLinuxAssets(TargetPlatform.linux_x64),
	const ReleaseBundleLinuxAssets(TargetPlatform.linux_arm64),
	const ReleaseAndroidApplication(),
	// This is a one-off rule for bundle and aot compat.
	const CopyFlutterBundle(),
	// Android targets,
	const DebugAndroidApplication(),
	const ProfileAndroidApplication(),
	// Android ABI specific AOT rules.
	androidArmProfileBundle,
	androidArm64ProfileBundle,
	androidx64ProfileBundle,
	androidArmReleaseBundle,
	androidArm64ReleaseBundle,
	androidx64ReleaseBundle,
	// Deferred component enabled AOT rules
	androidArmProfileDeferredComponentsBundle,
	androidArm64ProfileDeferredComponentsBundle,
	androidx64ProfileDeferredComponentsBundle,
	androidArmReleaseDeferredComponentsBundle,
	androidArm64ReleaseDeferredComponentsBundle,
	androidx64ReleaseDeferredComponentsBundle,
	// iOS targets
	const DebugIosApplicationBundle(),
	const ProfileIosApplicationBundle(),
	const ReleaseIosApplicationBundle(),
	// Windows targets
	const UnpackWindows(),
	const DebugBundleWindowsAssets(),
	const ProfileBundleWindowsAssets(),
	const ReleaseBundleWindowsAssets(),
	];

	/// Assemble provides a low level API to interact with the flutter tool build
	/// system.
	class AssembleCommand extends FlutterCommand {
	AssembleCommand({ bool verboseHelp = false, required BuildSystem buildSystem })
	: _buildSystem = buildSystem {
	argParser.addMultiOption(
	'define',
	abbr: 'd',
	valueHelp: 'target=key=value',
	help: 'Allows passing configuration to a target, as in "--define=target=key=value".',
	);
	argParser.addOption(
	'performance-measurement-file',
	help: 'Output individual target performance to a JSON file.'
	);
	argParser.addMultiOption(
	'input',
	abbr: 'i',
	help: 'Allows passing additional inputs with "--input=key=value". Unlike '
	'defines, additional inputs do not generate a new configuration; instead '
	'they are treated as dependencies of the targets that use them.'
	);
	argParser.addOption('depfile',
	help: 'A file path where a depfile will be written. '
	'This contains all build inputs and outputs in a Make-style syntax.'
	);
	argParser.addOption('build-inputs', help: 'A file path where a newline-separated '
	'file containing all inputs used will be written after a build. '
	'This file is not included as a build input or output. This file is not '
	'written if the build fails for any reason.');
	argParser.addOption('build-outputs', help: 'A file path where a newline-separated '
	'file containing all outputs created will be written after a build. '
	'This file is not included as a build input or output. This file is not '
	'written if the build fails for any reason.');
	argParser.addOption('output', abbr: 'o', help: 'A directory where output '
	'files will be written. Must be either absolute or relative from the '
	'root of the current Flutter project.',
	);
	usesExtraDartFlagOptions(verboseHelp: verboseHelp);
	usesDartDefineOption();
	argParser.addOption(
	'resource-pool-size',
	help: 'The maximum number of concurrent tasks the build system will run.',
	);
	}

	final BuildSystem _buildSystem;

	@override
	String get description => 'Assemble and build Flutter resources.';

	@override
	String get name => 'assemble';

	@override
	String get category => FlutterCommandCategory.project;

	@override
	Future<CustomDimensions> get usageValues async {
	final FlutterProject flutterProject = FlutterProject.current();
	try {
	return CustomDimensions(
	commandBuildBundleTargetPlatform: _environment.defines[kTargetPlatform],
	commandBuildBundleIsModule: flutterProject.isModule,
	);
	} on Exception {
	// We've failed to send usage.
	}
	return const CustomDimensions();
	}

	@override
	Future<Set<DevelopmentArtifact>> get requiredArtifacts async {
	final String? platform = _environment.defines[kTargetPlatform];
	if (platform == null) {
	return super.requiredArtifacts;
	}

	final TargetPlatform targetPlatform = getTargetPlatformForName(platform);
	final DevelopmentArtifact? artifact = artifactFromTargetPlatform(targetPlatform);
	if (artifact != null) {
	return <DevelopmentArtifact>{artifact};
	}
	return super.requiredArtifacts;
	}

	/// The target(s) we are building.
	List<Target> createTargets() {
	final ArgResults argumentResults = argResults!;
	if (argumentResults.rest.isEmpty) {
	throwToolExit('missing target name for flutter assemble.');
	}
	final String name = argumentResults.rest.first;
	final Map<String, Target> targetMap = <String, Target>{
	for (final Target target in _kDefaultTargets)
	target.name: target,
	};
	final List<Target> results = <Target>[
	for (final String targetName in argumentResults.rest)
	if (targetMap.containsKey(targetName))
	targetMap[targetName]!,
	];
	if (results.isEmpty) {
	throwToolExit('No target named "$name" defined.');
	}
	return results;
	}

	bool isDeferredComponentsTargets() {
	for (final String targetName in argResults!.rest) {
	if (deferredComponentsTargets.contains(targetName)) {
	return true;
	}
	}
	return false;
	}

	bool isDebug() {
	for (final String targetName in argResults!.rest) {
	if (targetName.contains('debug')) {
	return true;
	}
	}
	return false;
	}

	late final Environment _environment = _createEnvironment();

	/// The environmental configuration for a build invocation.
	Environment _createEnvironment() {
	final FlutterProject flutterProject = FlutterProject.current();
	String? output = stringArg('output');
	if (output == null) {
	throwToolExit('--output directory is required for assemble.');
	}
	// If path is relative, make it absolute from flutter project.
	if (globals.fs.path.isRelative(output)) {
	output = globals.fs.path.join(flutterProject.directory.path, output);
	}
	final Artifacts artifacts = globals.artifacts!;
	final Environment result = Environment(
	outputDir: globals.fs.directory(output),
	buildDir: flutterProject.directory
	.childDirectory('.dart_tool')
	.childDirectory('flutter_build'),
	projectDir: flutterProject.directory,
	defines: _parseDefines(stringsArg('define')),
	inputs: _parseDefines(stringsArg('input')),
	cacheDir: globals.cache.getRoot(),
	flutterRootDir: globals.fs.directory(Cache.flutterRoot),
	artifacts: artifacts,
	fileSystem: globals.fs,
	logger: globals.logger,
	processManager: globals.processManager,
	usage: globals.flutterUsage,
	platform: globals.platform,
	engineVersion: artifacts.isLocalEngine
	? null
	: globals.flutterVersion.engineRevision,
	generateDartPluginRegistry: true,
	);
	return result;
	}

	Map<String, String> _parseDefines(List<String> values) {
	final Map<String, String> results = <String, String>{};
	for (final String chunk in values) {
	final int indexEquals = chunk.indexOf('=');
	if (indexEquals == -1) {
	throwToolExit('Improperly formatted define flag: $chunk');
	}
	final String key = chunk.substring(0, indexEquals);
	final String value = chunk.substring(indexEquals + 1);
	results[key] = value;
	}
	final ArgResults argumentResults = argResults!;
	if (argumentResults.wasParsed(FlutterOptions.kExtraGenSnapshotOptions)) {
	results[kExtraGenSnapshotOptions] = (argumentResults[FlutterOptions.kExtraGenSnapshotOptions] as List<String>).join(',');
	}

	final Map<String, Object?> defineConfigJsonMap = extractDartDefineConfigJsonMap();
	final List<String> dartDefines = extractDartDefines(defineConfigJsonMap: defineConfigJsonMap);
	if (dartDefines.isNotEmpty){
	results[kDartDefines] = dartDefines.join(',');
	}

	results[kDeferredComponents] = 'false';
	if (FlutterProject.current().manifest.deferredComponents != null && isDeferredComponentsTargets() && !isDebug()) {
	results[kDeferredComponents] = 'true';
	}
	if (argumentResults.wasParsed(FlutterOptions.kExtraFrontEndOptions)) {
	results[kExtraFrontEndOptions] = (argumentResults[FlutterOptions.kExtraFrontEndOptions] as List<String>).join(',');
	}
	return results;
	}

	@override
	Future<FlutterCommandResult> runCommand() async {
	final List<Target> targets = createTargets();
	final List<Target> nonDeferredTargets = <Target>[];
	final List<Target> deferredTargets = <AndroidAotDeferredComponentsBundle>[];
	for (final Target target in targets) {
	if (deferredComponentsTargets.contains(target.name)) {
	deferredTargets.add(target);
	} else {
	nonDeferredTargets.add(target);
	}
	}
	Target? target;
	List<String> decodedDefines;
	try {
	decodedDefines = decodeDartDefines(_environment.defines, kDartDefines);
	} on FormatException {
	throwToolExit(
	'Error parsing assemble command: your generated configuration may be out of date. '
	"Try re-running 'flutter build ios' or the appropriate build command."
	);
	}
	if (FlutterProject.current().manifest.deferredComponents != null
	&& decodedDefines.contains('validate-deferred-components=true')
	&& deferredTargets.isNotEmpty
	&& !isDebug()) {
	// Add deferred components validation target that require loading units.
	target = DeferredComponentsGenSnapshotValidatorTarget(
	deferredComponentsDependencies: deferredTargets.cast<AndroidAotDeferredComponentsBundle>(),
	nonDeferredComponentsDependencies: nonDeferredTargets,
	title: 'Deferred components gen_snapshot validation',
	);
	} else if (targets.length > 1) {
	target = CompositeTarget(targets);
	} else if (targets.isNotEmpty) {
	target = targets.single;
	}
	final ArgResults argumentResults = argResults!;
	final BuildResult result = await _buildSystem.build(
	target!,
	_environment,
	buildSystemConfig: BuildSystemConfig(
	resourcePoolSize: argumentResults.wasParsed('resource-pool-size')
	? int.tryParse(stringArg('resource-pool-size')!)
	: null,
	),
	);
	if (!result.success) {
	for (final ExceptionMeasurement measurement in result.exceptions.values) {
	if (measurement.fatal \|\| globals.logger.isVerbose) {
	globals.printError('Target ${measurement.target} failed: ${measurement.exception}',
	stackTrace: globals.logger.isVerbose ? measurement.stackTrace : null,
	);
	}
	}
	throwToolExit('');
	}
	globals.printTrace('build succeeded.');

	if (argumentResults.wasParsed('build-inputs')) {
	writeListIfChanged(result.inputFiles, stringArg('build-inputs')!);
	}
	if (argumentResults.wasParsed('build-outputs')) {
	writeListIfChanged(result.outputFiles, stringArg('build-outputs')!);
	}
	if (argumentResults.wasParsed('performance-measurement-file')) {
	final File outFile = globals.fs.file(argumentResults['performance-measurement-file']);
	writePerformanceData(result.performance.values, outFile);
	}
	if (argumentResults.wasParsed('depfile')) {
	final File depfileFile = globals.fs.file(stringArg('depfile'));
	final Depfile depfile = Depfile(result.inputFiles, result.outputFiles);
	_environment.depFileService.writeToFile(depfile, globals.fs.file(depfileFile));
	}
	return FlutterCommandResult.success();
	}
	}

	@visibleForTesting
	void writeListIfChanged(List<File> files, String path) {
	final File file = globals.fs.file(path);
	final StringBuffer buffer = StringBuffer();
	// These files are already sorted.
	for (final File file in files) {
	buffer.writeln(file.path);
	}
	final String newContents = buffer.toString();
	if (!file.existsSync()) {
	file.writeAsStringSync(newContents);
	}
	final String currentContents = file.readAsStringSync();
	if (currentContents != newContents) {
	file.writeAsStringSync(newContents);
	}
	}

	/// Output performance measurement data in [outFile].
	@visibleForTesting
	void writePerformanceData(Iterable<PerformanceMeasurement> measurements, File outFile) {
	final Map<String, Object> jsonData = <String, Object>{
	'targets': <Object>[
	for (final PerformanceMeasurement measurement in measurements)
	<String, Object>{
	'name': measurement.analyticsName,
	'skipped': measurement.skipped,
	'succeeded': measurement.succeeded,
	'elapsedMilliseconds': measurement.elapsedMilliseconds,
	},
	],
	};
	if (!outFile.parent.existsSync()) {
	outFile.parent.createSync(recursive: true);
	}
	outFile.writeAsStringSync(json.encode(jsonData));
	}