Add first integration test + github workflow

A first integration test ensures that the background task runs and finishes.
This integration test is now running on every commit on Github Actions
via an emulator.

.github/workflows/main.yaml

@@ -7,7 +7,7 @@ jobs:
   flutter-tests:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: subosito/flutter-action@v2
       with:
         channel: 'stable'
@@ -36,3 +36,27 @@ jobs:
       with:
         files: coverage/lcov.info
         verbose: true
+
+
+  integration_test:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - uses: subosito/flutter-action@v2
+      with:
+        channel: 'stable'
+
+    - name: Install packages
+      run: flutter pub get
+
+    - name: Enable KVM
+      run: |
+        echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
+        sudo udevadm control --reload-rules
+        sudo udevadm trigger --name-match=kvm
+
+    - name: run integration test
+      uses: reactivecircus/android-emulator-runner@v2
+      with:
+        api-level: 29
+        script: flutter test integration_test

integration_test/background_interaction_test.dart

@@ -0,0 +1,47 @@
+import 'dart:async';
+import 'dart:isolate';
+import 'dart:ui';
+
+import 'package:app4training/background_task.dart';
+import 'package:app4training/data/globals.dart';
+import 'package:app4training/main.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:integration_test/integration_test.dart';
+import 'package:package_info_plus/package_info_plus.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+import 'package:workmanager/workmanager.dart';
+
+void main() async {
+  IntegrationTestWidgetsFlutterBinding.ensureInitialized();
+
+  testWidgets('Test that background task gets executed', (tester) async {
+    final prefs = await SharedPreferences.getInstance();
+    final packageInfo = await PackageInfo.fromPlatform();
+
+    final port = ReceivePort();
+    expect(IsolateNameServer.registerPortWithName(port.sendPort, 'test'), true);
+    final completer = Completer<String>();
+    port.listen((data) async {
+      // Waiting for the background task to finish its work
+      completer.complete(data);
+    });
+    await Workmanager().initialize(
+        backgroundTask, // The top level function, aka callbackDispatcher
+        isInDebugMode:
+            false // If enabled it will post a notification whenever the task is running. Handy for debugging tasks
+        );
+    await Workmanager().registerOneOffTask("task-identifier", "simpleTask",
+        initialDelay: const Duration(seconds: 2));
+
+    await tester.pumpWidget(ProviderScope(overrides: [
+      sharedPrefsProvider.overrideWithValue(prefs),
+      packageInfoProvider.overrideWithValue(packageInfo)
+    ], child: const App4Training()));
+    expect(find.text('Loading'), findsOneWidget);
+
+    // Wait for the background isolate to finish
+    final msg = await completer.future.timeout(const Duration(seconds: 10));
+    expect(msg, equals('success'));
+  });
+}

lib/background_task.dart

@@ -1,4 +1,5 @@
 import 'dart:io';
+import 'dart:ui';
 
 import 'package:app4training/data/globals.dart';
 import 'package:app4training/data/languages.dart';
@@ -30,6 +31,9 @@ void backgroundTask() {
   Workmanager().executeTask((task, inputData) async {
     try {
       await backgroundMain();
+      // For the integration test: Send a message to indicate we're finished
+      final sendPort = IsolateNameServer.lookupPortByName('test');
+      if (sendPort != null) sendPort.send('success');
     } catch (e) {
       await writeLog('Unexpected error while trying to run backgroundMain: $e');
     }

pubspec.lock

@@ -238,6 +238,11 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_driver:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   flutter_html:
     dependency: "direct main"
     description:
@@ -317,6 +322,11 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.2.0"
+  fuchsia_remote_debug_protocol:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   full_coverage:
     dependency: "direct dev"
     description:
@@ -373,6 +383,11 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "4.0.2"
+  integration_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   intl:
     dependency: "direct main"
     description:
@@ -621,6 +636,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.5.1"
+  process:
+    dependency: transitive
+    description:
+      name: process
+      sha256: "21e54fd2faf1b5bdd5102afd25012184a6793927648ea81eea80552ac9405b32"
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.0.2"
   pub_semver:
     dependency: transitive
     description:
@@ -842,6 +865,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.2.0"
+  sync_http:
+    dependency: transitive
+    description:
+      name: sync_http
+      sha256: "7f0cd72eca000d2e026bcd6f990b81d0ca06022ef4e32fb257b30d3d1014a961"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.3.1"
   term_glyph:
     dependency: transitive
     description:
@@ -994,6 +1025,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.4.3"
+  webdriver:
+    dependency: transitive
+    description:
+      name: webdriver
+      sha256: "003d7da9519e1e5f329422b36c4dcdf18d7d2978d1ba099ea4e45ba490ed845e"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.3"
   webkit_inspection_protocol:
     dependency: transitive
     description:

pubspec.yaml

@@ -67,6 +67,8 @@ dev_dependencies:
   full_coverage: ^1.0.0
   custom_lint: ^0.6.2
   riverpod_lint: ^2.0.3
+  integration_test:
+    sdk: flutter
 
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec