Integration test for FlutterTesterDevice. (#16424)

packages/flutter_tools/lib/src/artifacts.dart

@@ -31,7 +31,7 @@ enum Artifact {
   engineDartBinary,
 }
 
-String _artifactToFileName(Artifact artifact) {
+String _artifactToFileName(Artifact artifact, [TargetPlatform platform]) {
   switch (artifact) {
     case Artifact.dartIoEntriesTxt:
       return 'dart_io_entries.txt';
@@ -44,6 +44,9 @@ String _artifactToFileName(Artifact artifact) {
     case Artifact.genSnapshot:
       return 'gen_snapshot';
     case Artifact.flutterTester:
+      if (platform == TargetPlatform.windows_x64) {
+        return 'flutter_tester.exe';
+      }
       return 'flutter_tester';
     case Artifact.snapshotDart:
       return 'snapshot.dart';
@@ -181,7 +184,7 @@ class CachedArtifacts extends Artifacts {
       case Artifact.frontendServerSnapshotForEngineDartSdk:
         final String engineArtifactsPath = cache.getArtifactDirectory('engine').path;
         final String platformDirName = getNameForTargetPlatform(platform);
-        return fs.path.join(engineArtifactsPath, platformDirName, _artifactToFileName(artifact));
+        return fs.path.join(engineArtifactsPath, platformDirName, _artifactToFileName(artifact, platform));
       case Artifact.engineDartSdkPath:
         return dartSdkPath;
       case Artifact.engineDartBinary:

packages/flutter_tools/lib/src/tester/flutter_tester.dart

@@ -126,7 +126,7 @@ class FlutterTesterDevice extends Device {
     }
 
     try {
-      printTrace('$shellPath ${command.join(' ')}');
+      printTrace(command.join(' '));
 
       _process = await processManager.start(command);
       _process.stdout

packages/flutter_tools/test/integration/README.md

+# Integration tests
+
+These tests are not hermetic, and use actual Flutter SDK.
+While they don't require actual devices, they run `flutter_tester` to test
+Dart VM and Flutter integration.
+
+Some of these tests change the current directory for the process,
+so only one test can be run at a time. Use this command to run:
+
+```shell
+../../bin/cache/dart-sdk/bin/pub run test -j1
+```

packages/flutter_tools/test/integration/flutter_tester_test.dart

+// Copyright 2018 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 'dart:async';
+
+import 'package:file/file.dart';
+import 'package:flutter_tools/src/base/file_system.dart';
+import 'package:flutter_tools/src/build_info.dart';
+import 'package:flutter_tools/src/device.dart';
+import 'package:flutter_tools/src/tester/flutter_tester.dart';
+import 'package:test/test.dart';
+
+import '../src/context.dart';
+
+void main() {
+  Directory tempDir;
+  Directory oldCurrentDir;
+
+  setUp(() async {
+    tempDir = await fs.systemTempDirectory.createTemp('flutter_tester_device');
+    oldCurrentDir = fs.currentDirectory;
+    fs.currentDirectory = tempDir;
+  });
+
+  tearDown(() {
+    fs.currentDirectory = oldCurrentDir;
+    try {
+      tempDir?.deleteSync(recursive: true);
+      tempDir = null;
+    } catch (e) {
+      // Ignored.
+    }
+  });
+
+  group('FlutterTesterDevice', () {
+    FlutterTesterDevice device;
+
+    setUp(() {
+      device = new FlutterTesterDevice('flutter-tester');
+    });
+
+    Future<LaunchResult> start(String mainPath) async {
+      return await device.startApp(null,
+          mainPath: mainPath,
+          debuggingOptions: new DebuggingOptions.enabled(
+              const BuildInfo(BuildMode.debug, null)));
+    }
+
+    testUsingContext('start', () async {
+      _writePubspec();
+      _writePackages();
+
+      final String mainPath = fs.path.join('lib', 'main.dart');
+      _writeFile(mainPath, r'''
+import 'dart:async';
+void main() {
+  new Timer.periodic(const Duration(milliseconds: 1), (Timer timer) {
+    print('Hello!');
+  });
+}
+''');
+
+      final LaunchResult result = await start(mainPath);
+      expect(result.started, isTrue);
+      expect(result.observatoryUri, isNotNull);
+
+      final String line = await device.getLogReader().logLines.first;
+      expect(line, 'Hello!');
+
+      expect(await device.stopApp(null), isTrue);
+    });
+  });
+}
+
+void _writeFile(String path, String content) {
+  fs.file(path)
+    ..createSync(recursive: true)
+    ..writeAsStringSync(content);
+}
+
+void _writePackages() {
+  _writeFile('.packages', '''
+test:${fs.path.join(fs.currentDirectory.path, 'lib')}/
+''');
+}
+
+void _writePubspec() {
+  _writeFile('pubspec.yaml', '''
+name: test
+dependencies:
+  flutter:
+    sdk: flutter
+''');
+}