test: aggiungi test parsing JSON e widget test del dialog

parseTagName: v-prefix, body senza prefisso, JSON malformato, tag_name
assente, body vuoto. Widget test del dialog: titolo, versione nel testo,
pulsanti Più tardi e Scarica, chiusura dialog, chiamata MethodChannel
verificata con mock. 130/130 test passati.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

test/shared/services/update_service_test.dart

@@ -2,6 +2,28 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:biteplan/shared/services/update_service.dart';
 
 void main() {
+  group('UpdateService.parseTagName', () {
+    test('strips v prefix from tag_name', () {
+      expect(UpdateService.parseTagName('{"tag_name":"v2.1.0"}'), '2.1.0');
+    });
+
+    test('works without v prefix', () {
+      expect(UpdateService.parseTagName('{"tag_name":"2.1.0"}'), '2.1.0');
+    });
+
+    test('returns null for malformed JSON', () {
+      expect(UpdateService.parseTagName('not json'), isNull);
+    });
+
+    test('returns null when tag_name is missing', () {
+      expect(UpdateService.parseTagName('{"message":"Not Found"}'), isNull);
+    });
+
+    test('returns null for empty body', () {
+      expect(UpdateService.parseTagName(''), isNull);
+    });
+  });
+
   group('UpdateService.parseVersion', () {
     test('parses standard semver', () {
       expect(UpdateService.parseVersion('2.1.3'), [2, 1, 3]);

test/shared/widgets/update_dialog_test.dart

@@ -0,0 +1,82 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:biteplan/shared/widgets/update_dialog.dart';
+
+import '../../helpers/pump_app.dart';
+
+void main() {
+  setUp(() {
+    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+        .setMockMethodCallHandler(
+      const MethodChannel('com.davide.biteplan/launcher'),
+      (call) async => null,
+    );
+  });
+
+  tearDown(() {
+    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+        .setMockMethodCallHandler(
+      const MethodChannel('com.davide.biteplan/launcher'),
+      null,
+    );
+  });
+
+  Future<void> openDialog(WidgetTester tester, String version) async {
+    await tester.pumpApp(
+      Builder(
+        builder: (ctx) => TextButton(
+          onPressed: () => showUpdateDialog(ctx, version),
+          child: const Text('apri'),
+        ),
+      ),
+    );
+    await tester.tap(find.text('apri'));
+    await tester.pumpAndSettle();
+  }
+
+  testWidgets('mostra il titolo corretto', (tester) async {
+    await openDialog(tester, '2.1.0');
+    expect(find.text('Aggiornamento disponibile'), findsOneWidget);
+  });
+
+  testWidgets('mostra la versione nel contenuto', (tester) async {
+    await openDialog(tester, '2.1.0');
+    expect(find.textContaining('2.1.0'), findsOneWidget);
+  });
+
+  testWidgets('ha i pulsanti Più tardi e Scarica', (tester) async {
+    await openDialog(tester, '2.1.0');
+    expect(find.text('Più tardi'), findsOneWidget);
+    expect(find.text('Scarica'), findsOneWidget);
+  });
+
+  testWidgets('Più tardi chiude il dialog', (tester) async {
+    await openDialog(tester, '2.1.0');
+    await tester.tap(find.text('Più tardi'));
+    await tester.pumpAndSettle();
+    expect(find.text('Aggiornamento disponibile'), findsNothing);
+  });
+
+  testWidgets('Scarica chiude il dialog e chiama il launcher', (tester) async {
+    final calls = <MethodCall>[];
+    TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger
+        .setMockMethodCallHandler(
+      const MethodChannel('com.davide.biteplan/launcher'),
+      (call) async {
+        calls.add(call);
+        return null;
+      },
+    );
+
+    await openDialog(tester, '2.1.0');
+    await tester.tap(find.text('Scarica'));
+    await tester.pumpAndSettle();
+
+    expect(find.text('Aggiornamento disponibile'), findsNothing);
+    expect(calls, hasLength(1));
+    expect(calls.first.method, 'launch');
+    expect(calls.first.arguments['url'],
+        contains('github.com/davide3011/biteplan'));
+  });
+}