Add test

lib/screens/cart/total_price_text.dart

@@ -14,7 +14,7 @@ class TotalPriceText extends StatelessWidget {
       child: Padding(
         padding: const EdgeInsets.all(8.0),
         child: Text(
-          'Gesamtpreis: $totalPrice',
+          'Gesamtpreis: $totalPrice€',
           style: Theme.of(context).textTheme.labelLarge?.copyWith(fontSize: 24),
         ),
       ),

test/cart_store_test.dart

@@ -0,0 +1,19 @@
+import 'dart:async';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:thesis_shop/models/remote_resource.dart';
+import 'package:thesis_shop/store/cart_store.dart';
+
+import 'product_service_mock.dart';
+
+void main() {
+  test('test cart store', () async {
+    final cartStore = CartStore();
+    cartStore.updateProductList(const RemoteResource.finished(demoProducts));
+    final callbackStream = StreamController();
+    cartStore.addListener(() => callbackStream.add(true));
+    cartStore.increaseAmount(demoProducts.first);
+    expect(cartStore.amountOfProduct(demoProducts.first), 1);
+    await expectLater(callbackStream.stream, emits(true));
+  });
+}

test/product_service_mock.dart

@@ -1,15 +1,17 @@
 import 'package:thesis_shop/models/product.dart';
 import 'package:thesis_shop/service/product_service.dart';
 
+const demoProducts = [
+  Product(title: 'Bananen', price: 3),
+  Product(title: 'Äpfel', price: 2),
+  Product(title: 'Birnen', price: 2.5),
+  Product(title: 'Kirschen', price: 1.2),
+];
+
 class MockedProductService implements ProductService {
   @override
   Future<List<Product>> fetchProducts() async {
-    return const [
-      Product(title: 'Bananen', price: 3),
-      Product(title: 'Äpfel', price: 2),
-      Product(title: 'Birnen', price: 2.5),
-      Product(title: 'Kirschen', price: 1.2),
-    ];
+    return demoProducts;
   }
 
   @override

test/total_price_test.dart

@@ -0,0 +1,26 @@
+// ignore_for_file: unnecessary_cast
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:provider/provider.dart';
+import 'package:thesis_shop/screens/cart/total_price_text.dart';
+import 'package:thesis_shop/store/cart_store.dart';
+
+class CartStoreMock extends CartStore {
+  @override
+  double get totalPrice => 10.0;
+}
+
+void main() {
+  testWidgets('test total price', (tester) async {
+    final widgetTree = MaterialApp(
+      home: ChangeNotifierProvider.value(
+        value: CartStoreMock() as CartStore,
+        child: const TotalPriceText(),
+      ),
+    );
+    await tester.pumpWidget(widgetTree);
+    final correctText = find.text("Gesamtpreis: 10.00€");
+    expect(correctText, findsOneWidget);
+  });
+}