Flutter-Tests: ApiClient, Offline-Queue, Login-/Objektliste-Widgets

ApiClient nimmt jetzt einen injizierbaren http.Client entgegen (Testbarkeit,
kein Verhaltensunterschied im Betrieb). Tests mocken ihn mit mocktail statt
echter Netzwerkaufrufe. offline_queue_test.dart nutzt sqflite_common_ffi
(reines Dart) für die Queue-Logik ohne Gerät/Emulator: Erfolg entfernt
Eintrag, Netzwerkfehler bleibt "wartet", 4xx setzt "fehler" ohne Auto-Retry.
Dazu Widget-Tests für Login-Flow und Objektliste-Suchfilter.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CVgbozhYmuEhiEJHffRXCV

DEVLOG.md

@@ -2783,3 +2783,19 @@ Keine Commits in dieser Session.
 - deploy/mabea-eskalation.timer.template   | 12 ++++++
 
 ---
+## 2026-09-04 18:35 – 18:36 (0m)
+**Beschreibung:** Claude Code Session
+**Projekt:** flutter_app
+
+### Commits
+- c68d39b Flutter: Offline-Queue für Kontroll-Erfassung (Prompt 17-Härtung)
+
+### Geänderte Dateien
+- DEVLOG.md                                    |  30 ++++
+- flutter_app/DEVLOG.md                        |  15 ++
+- flutter_app/README.md                        |  18 ++-
+- flutter_app/lib/offline/queue.dart           | 205 ++++++++++++++++++++++++
+- flutter_app/lib/screens/kontroll_screen.dart | 225 +++++++++++++++++++--------
+- flutter_app/pubspec.yaml                     |   3 +
+
+---

flutter_app/DEVLOG.md

@@ -31,3 +31,19 @@ Keine Commits in dieser Session.
 - deploy/mabea-eskalation.timer.template   | 12 ++++++
 
 ---
+## 2026-09-04 18:36 – 18:38 (1m)
+**Beschreibung:** Claude Code Session
+**Projekt:** asb-material
+
+### Commits
+Keine Commits in dieser Session.
+
+### Geänderte Dateien
+- DEVLOG.md                                    |  30 ++++
+- flutter_app/DEVLOG.md                        |  15 ++
+- flutter_app/README.md                        |  18 ++-
+- flutter_app/lib/offline/queue.dart           | 205 ++++++++++++++++++++++++
+- flutter_app/lib/screens/kontroll_screen.dart | 225 +++++++++++++++++++--------
+- flutter_app/pubspec.yaml                     |   3 +
+
+---

flutter_app/README.md

@@ -54,7 +54,15 @@ Reconnect (`connectivity_plus`) und periodisch alle 15s - gleiches Muster wie
 `KontrollScreen` gleicht per 2s-Reconciliation-Loop den Anzeigezustand mit der
 Queue ab, Abschluss ist gesperrt, solange Einträge offen sind.
 
-## Bewusst noch nicht umgesetzt (Unterschied zur React-PWA)
+## Tests
 
-- Keine Tests (Flutter-Widget-/Integrationstests) - Sprintplan sieht Testphase 4
+```bash
-  primär für die PWA vor (Playwright); Android-Testabdeckung ist noch offen.
+flutter test
+```
+
+`http.Client` ist per Konstruktor injizierbar (`ApiClient(httpClient: ...)`), Tests
+mocken ihn mit `mocktail` statt echten Netzwerkaufrufen - kein Server/Emulator nötig.
+`test/offline_queue_test.dart` nutzt `sqflite_common_ffi` (reines Dart, keine
+Plattform-Channels), um die sqflite-Queue ohne Gerät/Emulator zu testen. Deckt ab:
+`ApiClient` (Login, Token-Header, Fehlerfälle), Offline-Queue (Erfolg/Netzwerkfehler/
+4xx-kein-Retry), Login-Screen und Objektliste-Suche als Widget-Tests.

flutter_app/lib/api/api_client.dart

@@ -17,9 +17,10 @@ class ApiException implements Exception {
 }
 
 class ApiClient {
-  ApiClient({required this.baseUrl});
+  ApiClient({required this.baseUrl, http.Client? httpClient}) : _http = httpClient ?? http.Client();
 
   final String baseUrl;
+  final http.Client _http;
   String? _token;
 
   Future<void> ladeToken() async {
@@ -40,7 +41,7 @@ class ApiClient {
   bool get istEingeloggt => _token != null;
 
   Future<String> login(String username, String password) async {
-    final response = await http.post(
+    final response = await _http.post(
       Uri.parse('$baseUrl/auth/login'),
       headers: {'Content-Type': 'application/x-www-form-urlencoded'},
       body: {'username': username, 'password': password},
@@ -69,19 +70,19 @@ class ApiClient {
     late http.Response response;
     switch (method) {
       case 'POST':
-        response = await http.post(uri, headers: headers, body: encodedBody);
+        response = await _http.post(uri, headers: headers, body: encodedBody);
         break;
       case 'PUT':
-        response = await http.put(uri, headers: headers, body: encodedBody);
+        response = await _http.put(uri, headers: headers, body: encodedBody);
         break;
       case 'PATCH':
-        response = await http.patch(uri, headers: headers, body: encodedBody);
+        response = await _http.patch(uri, headers: headers, body: encodedBody);
         break;
       case 'DELETE':
-        response = await http.delete(uri, headers: headers);
+        response = await _http.delete(uri, headers: headers);
         break;
       default:
-        response = await http.get(uri, headers: headers);
+        response = await _http.get(uri, headers: headers);
     }
 
     if (response.statusCode >= 400) {

flutter_app/pubspec.yaml

@@ -20,6 +20,8 @@ dev_dependencies:
   flutter_test:
     sdk: flutter
   flutter_lints: ^4.0.0
+  mocktail: ^1.0.4
+  sqflite_common_ffi: ^2.3.4+4
 
 flutter:
   uses-material-design: true

flutter_app/test/api_client_test.dart

@@ -0,0 +1,90 @@
+import 'dart:convert';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:http/http.dart' as http;
+import 'package:mocktail/mocktail.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'package:mabea_app/api/api_client.dart';
+
+class _MockClient extends Mock implements http.Client {}
+
+void main() {
+  late _MockClient httpClient;
+  late ApiClient apiClient;
+
+  setUp(() {
+    SharedPreferences.setMockInitialValues({});
+    httpClient = _MockClient();
+    apiClient = ApiClient(baseUrl: 'http://test.local/api/v1', httpClient: httpClient);
+  });
+
+  group('login', () {
+    test('speichert Token bei Erfolg', () async {
+      when(() => httpClient.post(
+            Uri.parse('http://test.local/api/v1/auth/login'),
+            headers: any(named: 'headers'),
+            body: any(named: 'body'),
+          )).thenAnswer(
+        (_) async => http.Response(jsonEncode({'access_token': 'abc-token'}), 200),
+      );
+
+      final token = await apiClient.login('mitarbeiter1', 'test-passwort-123');
+
+      expect(token, 'abc-token');
+      expect(apiClient.istEingeloggt, isTrue);
+    });
+
+    test('wirft ApiException bei falschem Passwort', () async {
+      when(() => httpClient.post(
+            Uri.parse('http://test.local/api/v1/auth/login'),
+            headers: any(named: 'headers'),
+            body: any(named: 'body'),
+          )).thenAnswer(
+        (_) async => http.Response(jsonEncode({'detail': 'falsch'}), 401),
+      );
+
+      expect(
+        () => apiClient.login('mitarbeiter1', 'falsch'),
+        throwsA(isA<ApiException>().having((e) => e.status, 'status', 401)),
+      );
+    });
+  });
+
+  group('request', () {
+    test('sendet Bearer-Token, sobald eingeloggt', () async {
+      when(() => httpClient.post(
+            Uri.parse('http://test.local/api/v1/auth/login'),
+            headers: any(named: 'headers'),
+            body: any(named: 'body'),
+          )).thenAnswer((_) async => http.Response(jsonEncode({'access_token': 'abc-token'}), 200));
+      await apiClient.login('mitarbeiter1', 'test-passwort-123');
+
+      when(() => httpClient.get(
+            Uri.parse('http://test.local/api/v1/objekte'),
+            headers: any(named: 'headers'),
+          )).thenAnswer((_) async => http.Response(jsonEncode([]), 200));
+
+      await apiClient.request('/objekte');
+
+      final captured = verify(() => httpClient.get(
+            Uri.parse('http://test.local/api/v1/objekte'),
+            headers: captureAny(named: 'headers'),
+          )).captured;
+      final headers = captured.single as Map<String, String>;
+      expect(headers['Authorization'], 'Bearer abc-token');
+    });
+
+    test('wirft ApiException bei 4xx-Antwort', () async {
+      when(() => httpClient.get(
+            Uri.parse('http://test.local/api/v1/objekte/1'),
+            headers: any(named: 'headers'),
+          )).thenAnswer((_) async => http.Response(jsonEncode({'detail': 'nicht gefunden'}), 404));
+
+      expect(
+        () => apiClient.request('/objekte/1'),
+        throwsA(isA<ApiException>().having((e) => e.status, 'status', 404)),
+      );
+    });
+  });
+}

flutter_app/test/offline_queue_test.dart

@@ -0,0 +1,96 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:http/http.dart' as http;
+import 'package:mocktail/mocktail.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+import 'package:sqflite_common_ffi/sqflite_ffi.dart';
+
+import 'package:mabea_app/api/api_client.dart';
+import 'package:mabea_app/offline/queue.dart';
+
+class _MockClient extends Mock implements http.Client {}
+
+/// OfflineQueue ist ein Singleton mit eigenem Datenbank-Handle (analog zur
+/// PWA-Queue, siehe frontend/src/offline/queue.ts) - für isolierte Tests
+/// hier über Reflection auf das private Feld nicht nötig: jeder Test nutzt
+/// eigene kontrolleId/materialId-Kombinationen, damit sich Einträge nicht
+/// überschneiden, plus Aufräumen am Ende.
+void main() {
+  setUpAll(() {
+    sqfliteFfiInit();
+    databaseFactory = databaseFactoryFfi;
+  });
+
+  late _MockClient httpClient;
+  late ApiClient apiClient;
+
+  setUp(() {
+    SharedPreferences.setMockInitialValues({});
+    httpClient = _MockClient();
+    apiClient = ApiClient(baseUrl: 'http://test.local/api/v1', httpClient: httpClient);
+  });
+
+  test('enqueue speichert Eintrag, verschwindet nach erfolgreicher Übertragung', () async {
+    const kontrolleId = 'k-erfolg';
+    when(() => httpClient.put(
+          Uri.parse('http://test.local/api/v1/kontrollen/$kontrolleId/positionen/10'),
+          headers: any(named: 'headers'),
+          body: any(named: 'body'),
+        )).thenAnswer((_) async => http.Response(jsonEncode({'id': 'kp-1'}), 200));
+
+    await OfflineQueue.instance.enqueue(kontrolleId: kontrolleId, materialId: 10, istmenge: '5');
+    var eintraege = await OfflineQueue.instance.eintraegeFuerKontrolle(kontrolleId);
+    expect(eintraege, hasLength(1));
+    expect(eintraege.single.status, 'wartet');
+
+    await OfflineQueue.instance.synchronisiere(apiClient);
+
+    eintraege = await OfflineQueue.instance.eintraegeFuerKontrolle(kontrolleId);
+    expect(eintraege, isEmpty);
+  });
+
+  test('Netzwerkfehler lässt Eintrag auf "wartet" stehen, kein Datenverlust', () async {
+    const kontrolleId = 'k-netzwerkfehler';
+    when(() => httpClient.put(
+          Uri.parse('http://test.local/api/v1/kontrollen/$kontrolleId/positionen/20'),
+          headers: any(named: 'headers'),
+          body: any(named: 'body'),
+        )).thenThrow(const SocketException('Keine Verbindung'));
+
+    await OfflineQueue.instance.enqueue(kontrolleId: kontrolleId, materialId: 20, istmenge: '3');
+    await OfflineQueue.instance.synchronisiere(apiClient);
+
+    final eintraege = await OfflineQueue.instance.eintraegeFuerKontrolle(kontrolleId);
+    expect(eintraege, hasLength(1));
+    expect(eintraege.single.status, 'wartet');
+  });
+
+  test('4xx-Antwort setzt Eintrag auf "fehler", kein Auto-Retry', () async {
+    const kontrolleId = 'k-4xx';
+    when(() => httpClient.put(
+          Uri.parse('http://test.local/api/v1/kontrollen/$kontrolleId/positionen/30'),
+          headers: any(named: 'headers'),
+          body: any(named: 'body'),
+        )).thenAnswer((_) async => http.Response(jsonEncode({'detail': 'Objekt gesperrt'}), 409));
+
+    await OfflineQueue.instance.enqueue(kontrolleId: kontrolleId, materialId: 30, istmenge: '3');
+    await OfflineQueue.instance.synchronisiere(apiClient);
+    var eintraege = await OfflineQueue.instance.eintraegeFuerKontrolle(kontrolleId);
+    expect(eintraege.single.status, 'fehler');
+    expect(eintraege.single.fehlerText, contains('409'));
+
+    // Erneuter Sync-Lauf darf den Fehler-Eintrag NICHT automatisch erneut senden.
+    await OfflineQueue.instance.synchronisiere(apiClient);
+    verify(() => httpClient.put(
+          Uri.parse('http://test.local/api/v1/kontrollen/$kontrolleId/positionen/30'),
+          headers: any(named: 'headers'),
+          body: any(named: 'body'),
+        )).called(1);
+
+    await OfflineQueue.instance.entferneFehlerEintrag(kontrolleId, 30);
+    eintraege = await OfflineQueue.instance.eintraegeFuerKontrolle(kontrolleId);
+    expect(eintraege, isEmpty);
+  });
+}

flutter_app/test/widget/login_screen_test.dart

@@ -0,0 +1,57 @@
+import 'dart:convert';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:http/http.dart' as http;
+import 'package:mocktail/mocktail.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'package:mabea_app/api/api_client.dart';
+import 'package:mabea_app/screens/login_screen.dart';
+
+class _MockClient extends Mock implements http.Client {}
+
+void main() {
+  setUpAll(() {
+    registerFallbackValue(Uri.parse('http://test.local'));
+  });
+
+  late _MockClient httpClient;
+  late ApiClient apiClient;
+
+  setUp(() {
+    SharedPreferences.setMockInitialValues({});
+    httpClient = _MockClient();
+    apiClient = ApiClient(baseUrl: 'http://test.local/api/v1', httpClient: httpClient);
+  });
+
+  testWidgets('erfolgreicher Login navigiert zur Objektliste', (tester) async {
+    when(() => httpClient.post(any(), headers: any(named: 'headers'), body: any(named: 'body')))
+        .thenAnswer((_) async => http.Response(jsonEncode({'access_token': 'abc-token'}), 200));
+    when(() => httpClient.get(any(), headers: any(named: 'headers')))
+        .thenAnswer((_) async => http.Response(jsonEncode([]), 200));
+
+    await tester.pumpWidget(MaterialApp(home: LoginScreen(apiClient: apiClient)));
+
+    await tester.enterText(find.widgetWithText(TextField, 'Login'), 'mitarbeiter1');
+    await tester.enterText(find.widgetWithText(TextField, 'Passwort'), 'test-passwort-123');
+    await tester.tap(find.widgetWithText(FilledButton, 'Anmelden'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Objekte'), findsOneWidget);
+  });
+
+  testWidgets('falsches Passwort zeigt Fehlermeldung, bleibt auf Login', (tester) async {
+    when(() => httpClient.post(any(), headers: any(named: 'headers'), body: any(named: 'body')))
+        .thenAnswer((_) async => http.Response(jsonEncode({'detail': 'falsch'}), 401));
+
+    await tester.pumpWidget(MaterialApp(home: LoginScreen(apiClient: apiClient)));
+
+    await tester.enterText(find.widgetWithText(TextField, 'Login'), 'mitarbeiter1');
+    await tester.enterText(find.widgetWithText(TextField, 'Passwort'), 'falsch');
+    await tester.tap(find.widgetWithText(FilledButton, 'Anmelden'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Login oder Passwort falsch'), findsOneWidget);
+  });
+}

flutter_app/test/widget/objekt_list_screen_test.dart

@@ -0,0 +1,51 @@
+import 'dart:convert';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:http/http.dart' as http;
+import 'package:mocktail/mocktail.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'package:mabea_app/api/api_client.dart';
+import 'package:mabea_app/screens/objekt_list_screen.dart';
+
+class _MockClient extends Mock implements http.Client {}
+
+void main() {
+  setUpAll(() {
+    registerFallbackValue(Uri.parse('http://test.local'));
+  });
+
+  late _MockClient httpClient;
+  late ApiClient apiClient;
+
+  setUp(() {
+    SharedPreferences.setMockInitialValues({});
+    httpClient = _MockClient();
+    apiClient = ApiClient(baseUrl: 'http://test.local/api/v1', httpClient: httpClient);
+  });
+
+  testWidgets('Suche filtert nach Name und Code', (tester) async {
+    when(() => httpClient.get(any(), headers: any(named: 'headers'))).thenAnswer(
+      (_) async => http.Response(
+        jsonEncode([
+          {'id': 1, 'name': 'Rucksack Handball', 'code': 'RK-00001', 'status': 'aktiv'},
+          {'id': 2, 'name': 'Fahrzeug 2', 'code': 'FZ-00002', 'status': 'aktiv'},
+        ]),
+        200,
+      ),
+    );
+
+    await tester.pumpWidget(MaterialApp(home: ObjektListScreen(apiClient: apiClient)));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Rucksack Handball'), findsOneWidget);
+    expect(find.text('Fahrzeug 2'), findsOneWidget);
+
+    await tester.enterText(find.byType(TextField).first, 'FZ-00002');
+    await tester.pumpAndSettle();
+
+    expect(find.text('Rucksack Handball'), findsNothing);
+    expect(find.text('Fahrzeug 2'), findsOneWidget);
+  });
+}