packages/flutter_tools/test/src/fake_process_manager.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 'dart:async';
 import 'dart:convert';
 import 'dart:io' as io show ProcessSignal, Process, ProcessStartMode, ProcessResult, systemEncoding;

 import 'package:file/file.dart';
 import 'package:meta/meta.dart';
 import 'package:process/process.dart';

 import 'test_wrapper.dart';

 export 'package:process/process.dart' show ProcessManager;

 typedef VoidCallback = void Function();

 /// A command for [FakeProcessManager].
 @immutable
 class FakeCommand {
   const FakeCommand({
     required this.command,
     this.workingDirectory,
     this.environment,
     this.encoding,
     this.duration = Duration.zero,
     this.onRun,
     this.exitCode = 0,
     this.stdout = '',
     this.stderr = '',
     this.completer,
     this.stdin,
     this.exception,
     this.outputFollowsExit = false,
   }) : assert(command != null),
        assert(duration != null),
        assert(exitCode != null);

   /// The exact commands that must be matched for this [FakeCommand] to be
   /// considered correct.
   final List<String> command;

   /// The exact working directory that must be matched for this [FakeCommand] to
   /// be considered correct.
   ///
   /// If this is null, the working directory is ignored.
   final String? workingDirectory;

   /// The environment that must be matched for this [FakeCommand] to be considered correct.
   ///
   /// If this is null, then the environment is ignored.
   ///
   /// Otherwise, each key in this environment must be present and must have a
   /// value that matches the one given here for the [FakeCommand] to match.
   final Map<String, String>? environment;

   /// The stdout and stderr encoding that must be matched for this [FakeCommand]
   /// to be considered correct.
   ///
   /// If this is null, then the encodings are ignored.
   final Encoding? encoding;

   /// The time to allow to elapse before returning the [exitCode], if this command
   /// is "executed".
   ///
   /// If you set this to a non-zero time, you should use a [FakeAsync] zone,
   /// otherwise the test will be artificially slow.
   final Duration duration;

   /// A callback that is run after [duration] expires but before the [exitCode]
   /// (and output) are passed back.
   final VoidCallback? onRun;

   /// The process' exit code.
   ///
   /// To simulate a never-ending process, set [duration] to a value greater than
   /// 15 minutes (the timeout for our tests).
   ///
   /// To simulate a crash, subtract the crash signal number from 256. For example,
   /// SIGPIPE (-13) is 243.
   final int exitCode;

   /// The output to simulate on stdout. This will be encoded as UTF-8 and
   /// returned in one go.
   final String stdout;

   /// The output to simulate on stderr. This will be encoded as UTF-8 and
   /// returned in one go.
   final String stderr;

   /// If provided, allows the command completion to be blocked until the future
   /// resolves.
   final Completer<void>? completer;

   /// An optional stdin sink that will be exposed through the resulting
   /// [FakeProcess].
   final IOSink? stdin;

   /// If provided, this exception will be thrown when the fake command is run.
   final Object? exception;

   /// Indicates that output will only be emitted after the `exitCode` [Future]
   /// on [io.Process] completes.
   final bool outputFollowsExit;

   void _matches(
     List<String> command,
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
   ) {
     expect(command, equals(this.command));
     if (this.workingDirectory != null) {
       expect(this.workingDirectory, workingDirectory);
     }
     if (this.environment != null) {
       expect(this.environment, environment);
     }
     if (this.encoding != null) {
       expect(this.encoding, encoding);
     }
   }
 }

 class _FakeProcess implements io.Process {
   _FakeProcess(
     this._exitCode,
     Duration duration,
     this.pid,
     this._stderr,
     IOSink? stdin,
     this._stdout,
     this._completer,
     bool outputFollowsExit,
   ) : exitCode = Future<void>.delayed(duration).then((void value) {
         if (_completer != null) {
           return _completer.future.then((void _) => _exitCode);
         }
         return _exitCode;
       }),
       stdin = stdin ?? IOSink(StreamController<List<int>>().sink)
   {
     if (_stderr == null) {
       stderr = const Stream<List<int>>.empty();
     } else if (outputFollowsExit) {
       stderr = Stream<List<int>>.fromFuture(exitCode.then((_) {
         return Future<List<int>>(() => utf8.encode(_stderr));
       }));
     } else {
       stderr = Stream<List<int>>.value(utf8.encode(_stderr));
     }

     if (_stdout == null) {
       stdout = const Stream<List<int>>.empty();
     } else if (outputFollowsExit) {
       stdout = Stream<List<int>>.fromFuture(exitCode.then((_) {
         return Future<List<int>>(() => utf8.encode(_stdout));
       }));
     } else {
       stdout = Stream<List<int>>.value(utf8.encode(_stdout));
     }
   }

   final int _exitCode;
   final Completer<void>? _completer;

   @override
   final Future<int> exitCode;

   @override
   final int pid;

   final String _stderr;

   @override
   late final Stream<List<int>> stderr;

   @override
   final IOSink stdin;

   @override
   late final Stream<List<int>> stdout;

   final String _stdout;

   @override
   bool kill([io.ProcessSignal signal = io.ProcessSignal.sigterm]) {
     // Killing a fake process has no effect.
     return false;
   }
 }

 abstract class FakeProcessManager implements ProcessManager {
   /// A fake [ProcessManager] which responds to all commands as if they had run
   /// instantaneously with an exit code of 0 and no output.
   factory FakeProcessManager.any() = _FakeAnyProcessManager;

   /// A fake [ProcessManager] which responds to particular commands with
   /// particular results.
   ///
   /// On creation, pass in a list of [FakeCommand] objects. When the
   /// [ProcessManager] methods such as [start] are invoked, the next
   /// [FakeCommand] must match (otherwise the test fails); its settings are used
   /// to simulate the result of running that command.
   ///
   /// If no command is found, then one is implied which immediately returns exit
   /// code 0 with no output.
   ///
   /// There is no logic to ensure that all the listed commands are run. Use
   /// [FakeCommand.onRun] to set a flag, or specify a sentinel command as your
   /// last command and verify its execution is successful, to ensure that all
   /// the specified commands are actually called.
   factory FakeProcessManager.list(List<FakeCommand> commands) = _SequenceProcessManager;
   factory FakeProcessManager.empty() => _SequenceProcessManager(<FakeCommand>[]);

   FakeProcessManager._();

   /// Adds a new [FakeCommand] to the current process manager.
   ///
   /// This can be used to configure test expectations after the [ProcessManager] has been
   /// provided to another interface.
   ///
   /// This is a no-op on [FakeProcessManager.any].
   void addCommand(FakeCommand command);

   /// Add multiple [FakeCommand] to the current process manager.
   void addCommands(Iterable<FakeCommand> commands) {
     commands.forEach(addCommand);
   }

   final Map<int, _FakeProcess> _fakeRunningProcesses = <int, _FakeProcess>{};

   /// Whether this fake has more [FakeCommand]s that are expected to run.
   ///
   /// This is always `true` for [FakeProcessManager.any].
   bool get hasRemainingExpectations;

   /// The expected [FakeCommand]s that have not yet run.
   List<FakeCommand> get _remainingExpectations;

   @protected
   FakeCommand findCommand(
     List<String> command,
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
   );

   int _pid = 9999;

   _FakeProcess _runCommand(
     List<String> command,
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
   ) {
     _pid += 1;
     final FakeCommand fakeCommand = findCommand(command, workingDirectory, environment, encoding);
     if (fakeCommand.exception != null) {
       assert(fakeCommand.exception is Exception || fakeCommand.exception is Error);
       throw fakeCommand.exception!; // ignore: only_throw_errors
     }
     if (fakeCommand.onRun != null) {
       fakeCommand.onRun!();
     }
     return _FakeProcess(
       fakeCommand.exitCode,
       fakeCommand.duration,
       _pid,
       fakeCommand.stderr,
       fakeCommand.stdin,
       fakeCommand.stdout,
       fakeCommand.completer,
       fakeCommand.outputFollowsExit,
     );
   }

   @override
   Future<io.Process> start(
     List<dynamic> command, {
     String? workingDirectory,
     Map<String, String>? environment,
     bool includeParentEnvironment = true, // ignored
     bool runInShell = false, // ignored
     io.ProcessStartMode mode = io.ProcessStartMode.normal, // ignored
   }) {
     final _FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, io.systemEncoding);
     if (process._completer != null) {
       _fakeRunningProcesses[process.pid] = process;
       process.exitCode.whenComplete(() {
         _fakeRunningProcesses.remove(process.pid);
       });
     }
     return Future<io.Process>.value(process);
   }

   @override
   Future<io.ProcessResult> run(
     List<dynamic> command, {
     String? workingDirectory,
     Map<String, String>? environment,
     bool includeParentEnvironment = true, // ignored
     bool runInShell = false, // ignored
     Encoding? stdoutEncoding = io.systemEncoding,
     Encoding? stderrEncoding = io.systemEncoding,
   }) async {
     final _FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, stdoutEncoding);
     await process.exitCode;
     return io.ProcessResult(
       process.pid,
       process._exitCode,
       stdoutEncoding == null ? process.stdout : await stdoutEncoding.decodeStream(process.stdout),
       stderrEncoding == null ? process.stderr : await stderrEncoding.decodeStream(process.stderr),
     );
   }

   @override
   io.ProcessResult runSync(
     List<dynamic> command, {
     String? workingDirectory,
     Map<String, String>? environment,
     bool includeParentEnvironment = true, // ignored
     bool runInShell = false, // ignored
     Encoding? stdoutEncoding = io.systemEncoding, // actual encoder is ignored
     Encoding? stderrEncoding = io.systemEncoding, // actual encoder is ignored
   }) {
     final _FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, stdoutEncoding);
     return io.ProcessResult(
       process.pid,
       process._exitCode,
       stdoutEncoding == null ? utf8.encode(process._stdout) : process._stdout,
       stderrEncoding == null ? utf8.encode(process._stderr) : process._stderr,
     );
   }

   /// Returns false if executable in [excludedExecutables].
   @override
   bool canRun(dynamic executable, {String? workingDirectory}) => !excludedExecutables.contains(executable);

   Set<String> excludedExecutables = <String>{};

   @override
   bool killPid(int pid, [io.ProcessSignal signal = io.ProcessSignal.sigterm]) {
     // Killing a fake process has no effect unless it has an attached completer.
     final _FakeProcess? fakeProcess = _fakeRunningProcesses[pid];
     if (fakeProcess == null) {
       return false;
     }
     if (fakeProcess._completer != null) {
       fakeProcess._completer!.complete();
     }
     return true;
   }
 }

 class _FakeAnyProcessManager extends FakeProcessManager {
   _FakeAnyProcessManager() : super._();

   @override
   FakeCommand findCommand(
     List<String> command,
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
   ) {
     return FakeCommand(
       command: command,
       workingDirectory: workingDirectory,
       environment: environment,
       encoding: encoding,
     );
   }

   @override
   void addCommand(FakeCommand command) { }

   @override
   bool get hasRemainingExpectations => true;

   @override
   List<FakeCommand> get _remainingExpectations => <FakeCommand>[];
 }

 class _SequenceProcessManager extends FakeProcessManager {
   _SequenceProcessManager(this._commands) : super._();

   final List<FakeCommand> _commands;

   @override
   FakeCommand findCommand(
     List<String> command,
     String? workingDirectory,
     Map<String, String>? environment,
     Encoding? encoding,
   ) {
     expect(_commands, isNotEmpty,
       reason: 'ProcessManager was told to execute $command (in $workingDirectory) '
               'but the FakeProcessManager.list expected no more processes.'
     );
     _commands.first._matches(command, workingDirectory, environment, encoding);
     return _commands.removeAt(0);
   }

   @override
   void addCommand(FakeCommand command) {
     _commands.add(command);
   }

   @override
   bool get hasRemainingExpectations => _commands.isNotEmpty;

   @override
   List<FakeCommand> get _remainingExpectations => _commands;
 }

 /// Matcher that successfully matches against a [FakeProcessManager] with
 /// no remaining expectations ([item.hasRemainingExpectations] returns false).
 const Matcher hasNoRemainingExpectations = _HasNoRemainingExpectations();

 class _HasNoRemainingExpectations extends Matcher {
   const _HasNoRemainingExpectations();

   @override
   bool matches(dynamic item, Map<dynamic, dynamic> matchState) =>
       item is FakeProcessManager && !item.hasRemainingExpectations;

   @override
   Description describe(Description description) =>
       description.add('a fake process manager with no remaining expectations');

   @override
   Description describeMismatch(
       dynamic item,
       Description description,
       Map<dynamic, dynamic> matchState,
       bool verbose,
       ) {
     final FakeProcessManager fakeProcessManager = item as FakeProcessManager;
     return description.add(
         'has remaining expectations:\n${fakeProcessManager._remainingExpectations.map((FakeCommand command) => command.command).join('\n')}');
   }
 }
	// 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 'dart:async';
	import 'dart:convert';
	import 'dart:io' as io show ProcessSignal, Process, ProcessStartMode, ProcessResult, systemEncoding;

	import 'package:file/file.dart';
	import 'package:meta/meta.dart';
	import 'package:process/process.dart';

	import 'test_wrapper.dart';

	export 'package:process/process.dart' show ProcessManager;

	typedef VoidCallback = void Function();

	/// A command for [FakeProcessManager].
	@immutable
	class FakeCommand {
	const FakeCommand({
	required this.command,
	this.workingDirectory,
	this.environment,
	this.encoding,
	this.duration = Duration.zero,
	this.onRun,
	this.exitCode = 0,
	this.stdout = '',
	this.stderr = '',
	this.completer,
	this.stdin,
	this.exception,
	this.outputFollowsExit = false,
	}) : assert(command != null),
	assert(duration != null),
	assert(exitCode != null);

	/// The exact commands that must be matched for this [FakeCommand] to be
	/// considered correct.
	final List<String> command;

	/// The exact working directory that must be matched for this [FakeCommand] to
	/// be considered correct.
	///
	/// If this is null, the working directory is ignored.
	final String? workingDirectory;

	/// The environment that must be matched for this [FakeCommand] to be considered correct.
	///
	/// If this is null, then the environment is ignored.
	///
	/// Otherwise, each key in this environment must be present and must have a
	/// value that matches the one given here for the [FakeCommand] to match.
	final Map<String, String>? environment;

	/// The stdout and stderr encoding that must be matched for this [FakeCommand]
	/// to be considered correct.
	///
	/// If this is null, then the encodings are ignored.
	final Encoding? encoding;

	/// The time to allow to elapse before returning the [exitCode], if this command
	/// is "executed".
	///
	/// If you set this to a non-zero time, you should use a [FakeAsync] zone,
	/// otherwise the test will be artificially slow.
	final Duration duration;

	/// A callback that is run after [duration] expires but before the [exitCode]
	/// (and output) are passed back.
	final VoidCallback? onRun;

	/// The process' exit code.
	///
	/// To simulate a never-ending process, set [duration] to a value greater than
	/// 15 minutes (the timeout for our tests).
	///
	/// To simulate a crash, subtract the crash signal number from 256. For example,
	/// SIGPIPE (-13) is 243.
	final int exitCode;

	/// The output to simulate on stdout. This will be encoded as UTF-8 and
	/// returned in one go.
	final String stdout;

	/// The output to simulate on stderr. This will be encoded as UTF-8 and
	/// returned in one go.
	final String stderr;

	/// If provided, allows the command completion to be blocked until the future
	/// resolves.
	final Completer<void>? completer;

	/// An optional stdin sink that will be exposed through the resulting
	/// [FakeProcess].
	final IOSink? stdin;

	/// If provided, this exception will be thrown when the fake command is run.
	final Object? exception;

	/// Indicates that output will only be emitted after the `exitCode` [Future]
	/// on [io.Process] completes.
	final bool outputFollowsExit;

	void _matches(
	List<String> command,
	String? workingDirectory,
	Map<String, String>? environment,
	Encoding? encoding,
	) {
	expect(command, equals(this.command));
	if (this.workingDirectory != null) {
	expect(this.workingDirectory, workingDirectory);
	}
	if (this.environment != null) {
	expect(this.environment, environment);
	}
	if (this.encoding != null) {
	expect(this.encoding, encoding);
	}
	}
	}

	class _FakeProcess implements io.Process {
	_FakeProcess(
	this._exitCode,
	Duration duration,
	this.pid,
	this._stderr,
	IOSink? stdin,
	this._stdout,
	this._completer,
	bool outputFollowsExit,
	) : exitCode = Future<void>.delayed(duration).then((void value) {
	if (_completer != null) {
	return _completer.future.then((void _) => _exitCode);
	}
	return _exitCode;
	}),
	stdin = stdin ?? IOSink(StreamController<List<int>>().sink)
	{
	if (_stderr == null) {
	stderr = const Stream<List<int>>.empty();
	} else if (outputFollowsExit) {
	stderr = Stream<List<int>>.fromFuture(exitCode.then((_) {
	return Future<List<int>>(() => utf8.encode(_stderr));
	}));
	} else {
	stderr = Stream<List<int>>.value(utf8.encode(_stderr));
	}

	if (_stdout == null) {
	stdout = const Stream<List<int>>.empty();
	} else if (outputFollowsExit) {
	stdout = Stream<List<int>>.fromFuture(exitCode.then((_) {
	return Future<List<int>>(() => utf8.encode(_stdout));
	}));
	} else {
	stdout = Stream<List<int>>.value(utf8.encode(_stdout));
	}
	}

	final int _exitCode;
	final Completer<void>? _completer;

	@override
	final Future<int> exitCode;

	@override
	final int pid;

	final String _stderr;

	@override
	late final Stream<List<int>> stderr;

	@override
	final IOSink stdin;

	@override
	late final Stream<List<int>> stdout;

	final String _stdout;

	@override
	bool kill([io.ProcessSignal signal = io.ProcessSignal.sigterm]) {
	// Killing a fake process has no effect.
	return false;
	}
	}

	abstract class FakeProcessManager implements ProcessManager {
	/// A fake [ProcessManager] which responds to all commands as if they had run
	/// instantaneously with an exit code of 0 and no output.
	factory FakeProcessManager.any() = _FakeAnyProcessManager;

	/// A fake [ProcessManager] which responds to particular commands with
	/// particular results.
	///
	/// On creation, pass in a list of [FakeCommand] objects. When the
	/// [ProcessManager] methods such as [start] are invoked, the next
	/// [FakeCommand] must match (otherwise the test fails); its settings are used
	/// to simulate the result of running that command.
	///
	/// If no command is found, then one is implied which immediately returns exit
	/// code 0 with no output.
	///
	/// There is no logic to ensure that all the listed commands are run. Use
	/// [FakeCommand.onRun] to set a flag, or specify a sentinel command as your
	/// last command and verify its execution is successful, to ensure that all
	/// the specified commands are actually called.
	factory FakeProcessManager.list(List<FakeCommand> commands) = _SequenceProcessManager;
	factory FakeProcessManager.empty() => _SequenceProcessManager(<FakeCommand>[]);

	FakeProcessManager._();

	/// Adds a new [FakeCommand] to the current process manager.
	///
	/// This can be used to configure test expectations after the [ProcessManager] has been
	/// provided to another interface.
	///
	/// This is a no-op on [FakeProcessManager.any].
	void addCommand(FakeCommand command);

	/// Add multiple [FakeCommand] to the current process manager.
	void addCommands(Iterable<FakeCommand> commands) {
	commands.forEach(addCommand);
	}

	final Map<int, _FakeProcess> _fakeRunningProcesses = <int, _FakeProcess>{};

	/// Whether this fake has more [FakeCommand]s that are expected to run.
	///
	/// This is always `true` for [FakeProcessManager.any].
	bool get hasRemainingExpectations;

	/// The expected [FakeCommand]s that have not yet run.
	List<FakeCommand> get _remainingExpectations;

	@protected
	FakeCommand findCommand(
	List<String> command,
	String? workingDirectory,
	Map<String, String>? environment,
	Encoding? encoding,
	);

	int _pid = 9999;

	_FakeProcess _runCommand(
	List<String> command,
	String? workingDirectory,
	Map<String, String>? environment,
	Encoding? encoding,
	) {
	_pid += 1;
	final FakeCommand fakeCommand = findCommand(command, workingDirectory, environment, encoding);
	if (fakeCommand.exception != null) {
	assert(fakeCommand.exception is Exception \|\| fakeCommand.exception is Error);
	throw fakeCommand.exception!; // ignore: only_throw_errors
	}
	if (fakeCommand.onRun != null) {
	fakeCommand.onRun!();
	}
	return _FakeProcess(
	fakeCommand.exitCode,
	fakeCommand.duration,
	_pid,
	fakeCommand.stderr,
	fakeCommand.stdin,
	fakeCommand.stdout,
	fakeCommand.completer,
	fakeCommand.outputFollowsExit,
	);
	}

	@override
	Future<io.Process> start(
	List<dynamic> command, {
	String? workingDirectory,
	Map<String, String>? environment,
	bool includeParentEnvironment = true, // ignored
	bool runInShell = false, // ignored
	io.ProcessStartMode mode = io.ProcessStartMode.normal, // ignored
	}) {
	final _FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, io.systemEncoding);
	if (process._completer != null) {
	_fakeRunningProcesses[process.pid] = process;
	process.exitCode.whenComplete(() {
	_fakeRunningProcesses.remove(process.pid);
	});
	}
	return Future<io.Process>.value(process);
	}

	@override
	Future<io.ProcessResult> run(
	List<dynamic> command, {
	String? workingDirectory,
	Map<String, String>? environment,
	bool includeParentEnvironment = true, // ignored
	bool runInShell = false, // ignored
	Encoding? stdoutEncoding = io.systemEncoding,
	Encoding? stderrEncoding = io.systemEncoding,
	}) async {
	final _FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, stdoutEncoding);
	await process.exitCode;
	return io.ProcessResult(
	process.pid,
	process._exitCode,
	stdoutEncoding == null ? process.stdout : await stdoutEncoding.decodeStream(process.stdout),
	stderrEncoding == null ? process.stderr : await stderrEncoding.decodeStream(process.stderr),
	);
	}

	@override
	io.ProcessResult runSync(
	List<dynamic> command, {
	String? workingDirectory,
	Map<String, String>? environment,
	bool includeParentEnvironment = true, // ignored
	bool runInShell = false, // ignored
	Encoding? stdoutEncoding = io.systemEncoding, // actual encoder is ignored
	Encoding? stderrEncoding = io.systemEncoding, // actual encoder is ignored
	}) {
	final _FakeProcess process = _runCommand(command.cast<String>(), workingDirectory, environment, stdoutEncoding);
	return io.ProcessResult(
	process.pid,
	process._exitCode,
	stdoutEncoding == null ? utf8.encode(process._stdout) : process._stdout,
	stderrEncoding == null ? utf8.encode(process._stderr) : process._stderr,
	);
	}

	/// Returns false if executable in [excludedExecutables].
	@override
	bool canRun(dynamic executable, {String? workingDirectory}) => !excludedExecutables.contains(executable);

	Set<String> excludedExecutables = <String>{};

	@override
	bool killPid(int pid, [io.ProcessSignal signal = io.ProcessSignal.sigterm]) {
	// Killing a fake process has no effect unless it has an attached completer.
	final _FakeProcess? fakeProcess = _fakeRunningProcesses[pid];
	if (fakeProcess == null) {
	return false;
	}
	if (fakeProcess._completer != null) {
	fakeProcess._completer!.complete();
	}
	return true;
	}
	}

	class _FakeAnyProcessManager extends FakeProcessManager {
	_FakeAnyProcessManager() : super._();

	@override
	FakeCommand findCommand(
	List<String> command,
	String? workingDirectory,
	Map<String, String>? environment,
	Encoding? encoding,
	) {
	return FakeCommand(
	command: command,
	workingDirectory: workingDirectory,
	environment: environment,
	encoding: encoding,
	);
	}

	@override
	void addCommand(FakeCommand command) { }

	@override
	bool get hasRemainingExpectations => true;

	@override
	List<FakeCommand> get _remainingExpectations => <FakeCommand>[];
	}

	class _SequenceProcessManager extends FakeProcessManager {
	_SequenceProcessManager(this._commands) : super._();

	final List<FakeCommand> _commands;

	@override
	FakeCommand findCommand(
	List<String> command,
	String? workingDirectory,
	Map<String, String>? environment,
	Encoding? encoding,
	) {
	expect(_commands, isNotEmpty,
	reason: 'ProcessManager was told to execute $command (in $workingDirectory) '
	'but the FakeProcessManager.list expected no more processes.'
	);
	_commands.first._matches(command, workingDirectory, environment, encoding);
	return _commands.removeAt(0);
	}

	@override
	void addCommand(FakeCommand command) {
	_commands.add(command);
	}

	@override
	bool get hasRemainingExpectations => _commands.isNotEmpty;

	@override
	List<FakeCommand> get _remainingExpectations => _commands;
	}

	/// Matcher that successfully matches against a [FakeProcessManager] with
	/// no remaining expectations ([item.hasRemainingExpectations] returns false).
	const Matcher hasNoRemainingExpectations = _HasNoRemainingExpectations();

	class _HasNoRemainingExpectations extends Matcher {
	const _HasNoRemainingExpectations();

	@override
	bool matches(dynamic item, Map<dynamic, dynamic> matchState) =>
	item is FakeProcessManager && !item.hasRemainingExpectations;

	@override
	Description describe(Description description) =>
	description.add('a fake process manager with no remaining expectations');

	@override
	Description describeMismatch(
	dynamic item,
	Description description,
	Map<dynamic, dynamic> matchState,
	bool verbose,
	) {
	final FakeProcessManager fakeProcessManager = item as FakeProcessManager;
	return description.add(
	'has remaining expectations:\n${fakeProcessManager._remainingExpectations.map((FakeCommand command) => command.command).join('\n')}');
	}
	}