Add integration_test template to create template (#70240)

packages/flutter_tools/templates/app/integration_test/app_test.dart.tmpl

+// This is a basic Flutter integration test.
+//
+// To perform an interaction with a widget in your test, use the WidgetTester
+// utility that Flutter provides. For example, you can send tap and scroll
+// gestures. You can also use WidgetTester to find child widgets in the widget
+// tree, read text, and verify that the values of widget properties are correct.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:integration_test/integration_test.dart';
+
+import 'package:{{projectName}}/main.dart' as app;
+
+void main() => run(_testMain);
+
+void _testMain() {
+  testWidgets('Counter increments smoke test', (WidgetTester tester) async {
+    // Build our app and trigger a frame.
+    app.main();
+
+    // Trigger a frame.
+    await tester.pumpAndSettle();
+
+{{^withPluginHook}}
+    // Verify that our counter starts at 0.
+    expect(find.text('0'), findsOneWidget);
+    expect(find.text('1'), findsNothing);
+
+    // Tap the '+' icon and trigger a frame.
+    await tester.tap(find.byIcon(Icons.add));
+    await tester.pump();
+
+    // Verify that our counter has incremented.
+    expect(find.text('0'), findsNothing);
+    expect(find.text('1'), findsOneWidget);
+{{/withPluginHook}}
+{{#withPluginHook}}
+    // Verify that platform version is retrieved.
+    expect(
+      find.byWidgetPredicate(
+        (Widget widget) => widget is Text &&
+                           widget.data.startsWith('Running on:'),
+      ),
+      findsOneWidget,
+    );
+{{/withPluginHook}}
+  });
+}

packages/flutter_tools/templates/app/integration_test/driver.dart.tmpl

+// This file is provided as a convenience for running integration tests via the
+// flutter drive command.
+//
+// flutter drive --driver integration_test/driver.dart --target integration_test/app_test.dart
+
+import 'package:integration_test/integration_test_driver.dart';
+
+Future<void> main() => integrationDriver();

packages/flutter_tools/templates/app/pubspec.yaml.tmpl

@@ -43,6 +43,8 @@ dependencies:
 dev_dependencies:
   flutter_test:
     sdk: flutter
+  integration_test:
+    sdk: flutter
 
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec

packages/flutter_tools/templates/template_manifest.json

@@ -33,6 +33,8 @@
         "templates/app/android.tmpl/gradle/wrapper/gradle-wrapper.properties",
         "templates/app/android.tmpl/gradle.properties.tmpl",
         "templates/app/android.tmpl/settings.gradle",
+        "templates/app/integration_test/app_test.dart.tmpl",
+        "templates/app/integration_test/driver.dart.tmpl",
         "templates/app/ios-objc.tmpl/Runner/AppDelegate.h",
         "templates/app/ios-objc.tmpl/Runner/AppDelegate.m",
         "templates/app/ios-objc.tmpl/Runner/main.m",

packages/flutter_tools/test/commands.shard/permeable/create_test.dart

@@ -299,6 +299,8 @@ void main() {
         'ios/Runner/main.m',
         'lib/main.dart',
         'test/widget_test.dart',
+        'integration_test/app_test.dart',
+        'integration_test/driver.dart',
       ],
     );
   }, overrides: <Type, Generator>{
@@ -364,6 +366,8 @@ void main() {
         'ios/Runner/main.m',
         'lib/main.dart',
         'test/widget_test.dart',
+        'integration_test/app_test.dart',
+        'integration_test/driver.dart',
       ],
     );
     return _runFlutterTest(projectDir);

packages/flutter_tools/test/integration.shard/integration_test_test.dart

+// 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:flutter_tools/src/base/file_system.dart';
+import 'package:flutter_tools/src/base/io.dart';
+
+import '../src/common.dart';
+import 'test_utils.dart';
+
+final String flutterBin = fileSystem.path.join(getFlutterRoot(), 'bin', platform.isWindows ? 'flutter.bat' : 'flutter');
+
+void main() {
+  Directory tempDir;
+  setUpAll(() {
+    tempDir = createResolvedTempDirectorySync('int_test.');
+  });
+
+  tearDownAll(() {
+    tryToDelete(tempDir);
+  });
+
+  testWithoutContext('flutter project default integration_test smoke test', () async {
+    const String projectName = 'integration_test_sample';
+    ProcessResult result = await processManager.run(
+      <String>[
+        flutterBin,
+        'create',
+        projectName,
+      ],
+      workingDirectory: tempDir.path,
+    );
+
+    expect(result.exitCode, 0);
+
+    final Directory projectDir = tempDir.childDirectory(projectName);
+    expect(projectDir.existsSync(), true);
+    final Directory integrationTestDir = projectDir.childDirectory('integration_test');
+    expect(integrationTestDir.existsSync(), true);
+    expect(integrationTestDir.childFile('driver.dart').existsSync(), true);
+    expect(integrationTestDir.childFile('app_test.dart').existsSync(), true);
+
+    result = await processManager.run(
+      <String>[
+        flutterBin,
+        'drive',
+        '-d', 'flutter-tester',
+        '--driver', 'integration_test/driver.dart',
+        '-t', 'integration_test/app_test.dart',
+      ],
+      workingDirectory: projectDir.path,
+    );
+
+    if (result.exitCode != 0) {
+      print('================================= STDOUT =======================================');
+      print(result.stdout);
+      print('================================= STDERR =======================================');
+      print(result.stderr);
+      fail('flutter drive failed, see output.');
+    }
+  });
+}