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

 // Copyright 2019 The Chromium 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:meta/meta.dart';

 import 'artifacts.dart';
 import 'base/context.dart';
 import 'base/file_system.dart';
 import 'base/platform.dart';
 import 'compile.dart';
 import 'globals.dart';
 import 'project.dart';

 const String _kMultiRootScheme = 'org-dartlang-app';

 /// The [CodeGenerator] instance.
 ///
 /// If [experimentalBuildEnabled] is false, this will contain an unsupported
 /// implementation.
 CodeGenerator get codeGenerator => context[CodeGenerator];

 /// Whether to attempt to build a flutter project using build* libraries.
 ///
 /// This requires both an experimental opt in via the environment variable
 /// 'FLUTTER_EXPERIMENTAL_BUILD' and that the project itself has a
 /// dependency on the package 'flutter_build' and 'build_runner.'
 bool get experimentalBuildEnabled {
   return _experimentalBuildEnabled ??= platform.environment['FLUTTER_EXPERIMENTAL_BUILD']?.toLowerCase() == 'true';
 }
 bool _experimentalBuildEnabled;

 @visibleForTesting
 set experimentalBuildEnabled(bool value) {
   _experimentalBuildEnabled = value;
 }

 /// A wrapper for a build_runner process which delegates to a generated
 /// build script.
 ///
 /// This is only enabled if [experimentalBuildEnabled] is true, and only for
 /// external flutter users.
 abstract class CodeGenerator {
   const CodeGenerator();

   /// Run a partial build include code generators but not kernel.
   Future<void> generate({@required String mainPath}) async {
     await build(
       mainPath: mainPath,
       aot: false,
       linkPlatformKernelIn: false,
       trackWidgetCreation: false,
       targetProductVm: false,
       disableKernelGeneration: true,
     );
   }

   /// Run a full build and return the resulting .packages and dill file.
   ///
   /// The defines of the build command are the arguments required in the
   /// flutter_build kernel builder.
   Future<CodeGenerationResult> build({
     @required String mainPath,
     @required bool aot,
     @required bool linkPlatformKernelIn,
     @required bool trackWidgetCreation,
     @required bool targetProductVm,
     List<String> extraFrontEndOptions = const <String>[],
     bool disableKernelGeneration = false,
   });

   /// Starts a persistent code generting daemon.
   ///
   /// The defines of the daemon command are the arguments required in the
   /// flutter_build kernel builder.
   Future<CodegenDaemon> daemon({
     @required String mainPath,
     bool linkPlatformKernelIn = false,
     bool targetProductVm = false,
     bool trackWidgetCreation = false,
     List<String> extraFrontEndOptions = const <String>[],
   });

   /// Invalidates a generated build script by deleting it.
   ///
   /// Must be called any time a pubspec file update triggers a corresponding change
   /// in .packages.
   Future<void> invalidateBuildScript();

   // Generates a synthetic package under .dart_tool/flutter_tool which is in turn
   // used to generate a build script.
   Future<void> generateBuildScript();
 }

 class UnsupportedCodeGenerator extends CodeGenerator {
   const UnsupportedCodeGenerator();

   @override
   Future<CodeGenerationResult> build({
     String mainPath,
     bool aot,
     bool linkPlatformKernelIn,
     bool trackWidgetCreation,
     bool targetProductVm,
     List<String> extraFrontEndOptions = const <String> [],
     bool disableKernelGeneration = false,
   }) {
     throw UnsupportedError('build_runner is not currently supported.');
   }

   @override
   Future<void> generateBuildScript() {
     throw UnsupportedError('build_runner is not currently supported.');
   }

   @override
   Future<void> invalidateBuildScript() {
     throw UnsupportedError('build_runner is not currently supported.');
   }

   @override
   Future<CodegenDaemon> daemon({
     String mainPath,
     bool linkPlatformKernelIn = false,
     bool targetProductVm = false,
     bool trackWidgetCreation = false,
     List<String> extraFrontEndOptions = const <String> [],
   }) {
     throw UnsupportedError('build_runner is not currently supported.');
   }
 }

 abstract class CodegenDaemon {
   /// Whether the previously enqueued build was successful.
   Stream<CodegenStatus> get buildResults;

   CodegenStatus get lastStatus;

   /// Starts a new build.
   void startBuild();

   File get packagesFile;

   File get dillFile;
 }

 /// The result of running a build through a [CodeGenerator].
 ///
 /// If no dill or packages file is generated, they will be null.
 class CodeGenerationResult {
   const CodeGenerationResult(this.packagesFile, this.dillFile);

   final File packagesFile;
   final File dillFile;
 }

 /// An implementation of the [KernelCompiler] which delegates to build_runner.
 ///
 /// Only a subset of the arguments provided to the [KernelCompiler] are
 /// supported here. Using the build pipeline implies a fixed multiroot
 /// filesystem and requires a pubspec.
 ///
 /// This is only safe to use if [experimentalBuildEnabled] is true.
 class CodeGeneratingKernelCompiler implements KernelCompiler {
   const CodeGeneratingKernelCompiler();

   @override
   Future<CompilerOutput> compile({
     String mainPath,
     String outputFilePath,
     bool linkPlatformKernelIn = false,
     bool aot = false,
     bool trackWidgetCreation,
     List<String> extraFrontEndOptions,
     String incrementalCompilerByteStorePath,
     bool targetProductVm = false,
     // These arguments are currently unused.
     String sdkRoot,
     String packagesPath,
     List<String> fileSystemRoots,
     String fileSystemScheme,
     String depFilePath,
     TargetModel targetModel = TargetModel.flutter,
   }) async {
     if (fileSystemRoots != null || fileSystemScheme != null || depFilePath != null || targetModel != null || sdkRoot != null || packagesPath != null) {
       printTrace('fileSystemRoots, fileSystemScheme, depFilePath, targetModel,'
         'sdkRoot, packagesPath are not supported when using the experimental '
         'build* pipeline');
     }
     try {
       final CodeGenerationResult buildResult = await codeGenerator.build(
         aot: aot,
         linkPlatformKernelIn: linkPlatformKernelIn,
         trackWidgetCreation: trackWidgetCreation,
         mainPath: mainPath,
         targetProductVm: targetProductVm,
         extraFrontEndOptions: extraFrontEndOptions,
       );
       final File outputFile = fs.file(outputFilePath);
       if (!await outputFile.exists()) {
         await outputFile.create();
       }
       await outputFile.writeAsBytes(await buildResult.dillFile.readAsBytes());
       return CompilerOutput(outputFilePath, 0);
     } on Exception catch (err) {
       printError('Compilation Failed: $err');
       return const CompilerOutput(null, 1);
     }
   }
 }

 /// An implementation of a [ResidentCompiler] which runs a [BuildRunner] before
 /// talking to the CFE.
 class CodeGeneratingResidentCompiler implements ResidentCompiler {
   CodeGeneratingResidentCompiler._(this._residentCompiler, this._codegenDaemon);

   /// Creates a new [ResidentCompiler] and configures a [BuildDaemonClient] to
   /// run builds.
   static Future<CodeGeneratingResidentCompiler> create({
     @required String mainPath,
     bool trackWidgetCreation = false,
     CompilerMessageConsumer compilerMessageConsumer = printError,
     bool unsafePackageSerialization = false,
   }) async {
     final FlutterProject flutterProject = await FlutterProject.current();
     final CodegenDaemon codegenDaemon = await codeGenerator.daemon(
       extraFrontEndOptions: <String>[],
       linkPlatformKernelIn: false,
       mainPath: mainPath,
       targetProductVm: false,
       trackWidgetCreation: trackWidgetCreation,
     );
     codegenDaemon.startBuild();
     final CodegenStatus status = await codegenDaemon.buildResults.firstWhere((CodegenStatus status) {
       return status ==CodegenStatus.Succeeded || status == CodegenStatus.Failed;
     });
     if (status == CodegenStatus.Failed) {
       printError('Codegeneration failed, halting build.');
     }
     final ResidentCompiler residentCompiler = ResidentCompiler(
       artifacts.getArtifactPath(Artifact.flutterPatchedSdkPath),
       trackWidgetCreation: trackWidgetCreation,
       packagesPath: codegenDaemon.packagesFile.path,
       fileSystemRoots: <String>[
         fs.path.join(flutterProject.generated.absolute.path, 'lib${platform.pathSeparator}'),
         fs.path.join(flutterProject.directory.path, 'lib${platform.pathSeparator}'),
       ],
       fileSystemScheme: _kMultiRootScheme,
       targetModel: TargetModel.flutter,
       unsafePackageSerialization: unsafePackageSerialization,
     );
     return CodeGeneratingResidentCompiler._(residentCompiler, codegenDaemon);
   }

   final ResidentCompiler _residentCompiler;
   final CodegenDaemon _codegenDaemon;

   @override
   void accept() {
     _residentCompiler.accept();
   }

   @override
   Future<CompilerOutput> compileExpression(String expression, List<String> definitions, List<String> typeDefinitions, String libraryUri, String klass, bool isStatic) {
     return _residentCompiler.compileExpression(expression, definitions, typeDefinitions, libraryUri, klass, isStatic);
   }

   @override
   Future<CompilerOutput> recompile(String mainPath, List<String> invalidatedFiles, {String outputPath, String packagesFilePath}) async {
     if (_codegenDaemon.lastStatus != CodegenStatus.Succeeded && _codegenDaemon.lastStatus != CodegenStatus.Failed) {
       await _codegenDaemon.buildResults.firstWhere((CodegenStatus status) {
         return status ==CodegenStatus.Succeeded || status == CodegenStatus.Failed;
       });
     }
     if (_codegenDaemon.lastStatus == CodegenStatus.Failed) {
       printError('Codegeneration failed, halting build.');
     }
     // Delete this file so that the frontend_server can handle multi-root.
     // TODO(jonahwilliams): investigate frontend_server behavior in the presence
     // of multi-root and initialize from dill.
     if (await fs.file(outputPath).exists()) {
       await fs.file(outputPath).delete();
     }
     return _residentCompiler.recompile(
       mainPath,
       invalidatedFiles,
       outputPath: outputPath,
       packagesFilePath: _codegenDaemon.packagesFile.path,
     );
   }

   @override
   Future<CompilerOutput> reject() {
     return _residentCompiler.reject();
   }

   @override
   void reset() {
     _residentCompiler.reset();
   }

   @override
   Future<void> shutdown() {
     return _residentCompiler.shutdown();
   }
 }

 /// The current status of a codegen build.
 enum CodegenStatus {
   /// The build has started running.
   ///
   /// If this is the current status when running a hot reload, an additional build does
   /// not need to be started.
   Started,
   /// The build succeeded.
   Succeeded,
   /// The build failed.
   Failed
 }
	// Copyright 2019 The Chromium 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:meta/meta.dart';

	import 'artifacts.dart';
	import 'base/context.dart';
	import 'base/file_system.dart';
	import 'base/platform.dart';
	import 'compile.dart';
	import 'globals.dart';
	import 'project.dart';

	const String _kMultiRootScheme = 'org-dartlang-app';

	/// The [CodeGenerator] instance.
	///
	/// If [experimentalBuildEnabled] is false, this will contain an unsupported
	/// implementation.
	CodeGenerator get codeGenerator => context[CodeGenerator];

	/// Whether to attempt to build a flutter project using build* libraries.
	///
	/// This requires both an experimental opt in via the environment variable
	/// 'FLUTTER_EXPERIMENTAL_BUILD' and that the project itself has a
	/// dependency on the package 'flutter_build' and 'build_runner.'
	bool get experimentalBuildEnabled {
	return _experimentalBuildEnabled ??= platform.environment['FLUTTER_EXPERIMENTAL_BUILD']?.toLowerCase() == 'true';
	}
	bool _experimentalBuildEnabled;

	@visibleForTesting
	set experimentalBuildEnabled(bool value) {
	_experimentalBuildEnabled = value;
	}

	/// A wrapper for a build_runner process which delegates to a generated
	/// build script.
	///
	/// This is only enabled if [experimentalBuildEnabled] is true, and only for
	/// external flutter users.
	abstract class CodeGenerator {
	const CodeGenerator();

	/// Run a partial build include code generators but not kernel.
	Future<void> generate({@required String mainPath}) async {
	await build(
	mainPath: mainPath,
	aot: false,
	linkPlatformKernelIn: false,
	trackWidgetCreation: false,
	targetProductVm: false,
	disableKernelGeneration: true,
	);
	}

	/// Run a full build and return the resulting .packages and dill file.
	///
	/// The defines of the build command are the arguments required in the
	/// flutter_build kernel builder.
	Future<CodeGenerationResult> build({
	@required String mainPath,
	@required bool aot,
	@required bool linkPlatformKernelIn,
	@required bool trackWidgetCreation,
	@required bool targetProductVm,
	List<String> extraFrontEndOptions = const <String>[],
	bool disableKernelGeneration = false,
	});

	/// Starts a persistent code generting daemon.
	///
	/// The defines of the daemon command are the arguments required in the
	/// flutter_build kernel builder.
	Future<CodegenDaemon> daemon({
	@required String mainPath,
	bool linkPlatformKernelIn = false,
	bool targetProductVm = false,
	bool trackWidgetCreation = false,
	List<String> extraFrontEndOptions = const <String>[],
	});

	/// Invalidates a generated build script by deleting it.
	///
	/// Must be called any time a pubspec file update triggers a corresponding change
	/// in .packages.
	Future<void> invalidateBuildScript();

	// Generates a synthetic package under .dart_tool/flutter_tool which is in turn
	// used to generate a build script.
	Future<void> generateBuildScript();
	}

	class UnsupportedCodeGenerator extends CodeGenerator {
	const UnsupportedCodeGenerator();

	@override
	Future<CodeGenerationResult> build({
	String mainPath,
	bool aot,
	bool linkPlatformKernelIn,
	bool trackWidgetCreation,
	bool targetProductVm,
	List<String> extraFrontEndOptions = const <String> [],
	bool disableKernelGeneration = false,
	}) {
	throw UnsupportedError('build_runner is not currently supported.');
	}

	@override
	Future<void> generateBuildScript() {
	throw UnsupportedError('build_runner is not currently supported.');
	}

	@override
	Future<void> invalidateBuildScript() {
	throw UnsupportedError('build_runner is not currently supported.');
	}

	@override
	Future<CodegenDaemon> daemon({
	String mainPath,
	bool linkPlatformKernelIn = false,
	bool targetProductVm = false,
	bool trackWidgetCreation = false,
	List<String> extraFrontEndOptions = const <String> [],
	}) {
	throw UnsupportedError('build_runner is not currently supported.');
	}
	}

	abstract class CodegenDaemon {
	/// Whether the previously enqueued build was successful.
	Stream<CodegenStatus> get buildResults;

	CodegenStatus get lastStatus;

	/// Starts a new build.
	void startBuild();

	File get packagesFile;

	File get dillFile;
	}

	/// The result of running a build through a [CodeGenerator].
	///
	/// If no dill or packages file is generated, they will be null.
	class CodeGenerationResult {
	const CodeGenerationResult(this.packagesFile, this.dillFile);

	final File packagesFile;
	final File dillFile;
	}

	/// An implementation of the [KernelCompiler] which delegates to build_runner.
	///
	/// Only a subset of the arguments provided to the [KernelCompiler] are
	/// supported here. Using the build pipeline implies a fixed multiroot
	/// filesystem and requires a pubspec.
	///
	/// This is only safe to use if [experimentalBuildEnabled] is true.
	class CodeGeneratingKernelCompiler implements KernelCompiler {
	const CodeGeneratingKernelCompiler();

	@override
	Future<CompilerOutput> compile({
	String mainPath,
	String outputFilePath,
	bool linkPlatformKernelIn = false,
	bool aot = false,
	bool trackWidgetCreation,
	List<String> extraFrontEndOptions,
	String incrementalCompilerByteStorePath,
	bool targetProductVm = false,
	// These arguments are currently unused.
	String sdkRoot,
	String packagesPath,
	List<String> fileSystemRoots,
	String fileSystemScheme,
	String depFilePath,
	TargetModel targetModel = TargetModel.flutter,
	}) async {
	if (fileSystemRoots != null \|\| fileSystemScheme != null \|\| depFilePath != null \|\| targetModel != null \|\| sdkRoot != null \|\| packagesPath != null) {
	printTrace('fileSystemRoots, fileSystemScheme, depFilePath, targetModel,'
	'sdkRoot, packagesPath are not supported when using the experimental '
	'build* pipeline');
	}
	try {
	final CodeGenerationResult buildResult = await codeGenerator.build(
	aot: aot,
	linkPlatformKernelIn: linkPlatformKernelIn,
	trackWidgetCreation: trackWidgetCreation,
	mainPath: mainPath,
	targetProductVm: targetProductVm,
	extraFrontEndOptions: extraFrontEndOptions,
	);
	final File outputFile = fs.file(outputFilePath);
	if (!await outputFile.exists()) {
	await outputFile.create();
	}
	await outputFile.writeAsBytes(await buildResult.dillFile.readAsBytes());
	return CompilerOutput(outputFilePath, 0);
	} on Exception catch (err) {
	printError('Compilation Failed: $err');
	return const CompilerOutput(null, 1);
	}
	}
	}

	/// An implementation of a [ResidentCompiler] which runs a [BuildRunner] before
	/// talking to the CFE.
	class CodeGeneratingResidentCompiler implements ResidentCompiler {
	CodeGeneratingResidentCompiler._(this._residentCompiler, this._codegenDaemon);

	/// Creates a new [ResidentCompiler] and configures a [BuildDaemonClient] to
	/// run builds.
	static Future<CodeGeneratingResidentCompiler> create({
	@required String mainPath,
	bool trackWidgetCreation = false,
	CompilerMessageConsumer compilerMessageConsumer = printError,
	bool unsafePackageSerialization = false,
	}) async {
	final FlutterProject flutterProject = await FlutterProject.current();
	final CodegenDaemon codegenDaemon = await codeGenerator.daemon(
	extraFrontEndOptions: <String>[],
	linkPlatformKernelIn: false,
	mainPath: mainPath,
	targetProductVm: false,
	trackWidgetCreation: trackWidgetCreation,
	);
	codegenDaemon.startBuild();
	final CodegenStatus status = await codegenDaemon.buildResults.firstWhere((CodegenStatus status) {
	return status ==CodegenStatus.Succeeded \|\| status == CodegenStatus.Failed;
	});
	if (status == CodegenStatus.Failed) {
	printError('Codegeneration failed, halting build.');
	}
	final ResidentCompiler residentCompiler = ResidentCompiler(
	artifacts.getArtifactPath(Artifact.flutterPatchedSdkPath),
	trackWidgetCreation: trackWidgetCreation,
	packagesPath: codegenDaemon.packagesFile.path,
	fileSystemRoots: <String>[
	fs.path.join(flutterProject.generated.absolute.path, 'lib${platform.pathSeparator}'),
	fs.path.join(flutterProject.directory.path, 'lib${platform.pathSeparator}'),
	],
	fileSystemScheme: _kMultiRootScheme,
	targetModel: TargetModel.flutter,
	unsafePackageSerialization: unsafePackageSerialization,
	);
	return CodeGeneratingResidentCompiler._(residentCompiler, codegenDaemon);
	}

	final ResidentCompiler _residentCompiler;
	final CodegenDaemon _codegenDaemon;

	@override
	void accept() {
	_residentCompiler.accept();
	}

	@override
	Future<CompilerOutput> compileExpression(String expression, List<String> definitions, List<String> typeDefinitions, String libraryUri, String klass, bool isStatic) {
	return _residentCompiler.compileExpression(expression, definitions, typeDefinitions, libraryUri, klass, isStatic);
	}

	@override
	Future<CompilerOutput> recompile(String mainPath, List<String> invalidatedFiles, {String outputPath, String packagesFilePath}) async {
	if (_codegenDaemon.lastStatus != CodegenStatus.Succeeded && _codegenDaemon.lastStatus != CodegenStatus.Failed) {
	await _codegenDaemon.buildResults.firstWhere((CodegenStatus status) {
	return status ==CodegenStatus.Succeeded \|\| status == CodegenStatus.Failed;
	});
	}
	if (_codegenDaemon.lastStatus == CodegenStatus.Failed) {
	printError('Codegeneration failed, halting build.');
	}
	// Delete this file so that the frontend_server can handle multi-root.
	// TODO(jonahwilliams): investigate frontend_server behavior in the presence
	// of multi-root and initialize from dill.
	if (await fs.file(outputPath).exists()) {
	await fs.file(outputPath).delete();
	}
	return _residentCompiler.recompile(
	mainPath,
	invalidatedFiles,
	outputPath: outputPath,
	packagesFilePath: _codegenDaemon.packagesFile.path,
	);
	}

	@override
	Future<CompilerOutput> reject() {
	return _residentCompiler.reject();
	}

	@override
	void reset() {
	_residentCompiler.reset();
	}

	@override
	Future<void> shutdown() {
	return _residentCompiler.shutdown();
	}
	}

	/// The current status of a codegen build.
	enum CodegenStatus {
	/// The build has started running.
	///
	/// If this is the current status when running a hot reload, an additional build does
	/// not need to be started.
	Started,
	/// The build succeeded.
	Succeeded,
	/// The build failed.
	Failed
	}