new directory

lib/database/database.dart

@@ -10,6 +10,7 @@ class Database{
   Future<Database> get database async {
     if (_database != null) return _database!;
     _database = await _initDB('database.db');
+
     return _database!;
   }
 

lib/model/promemoria.dart

@@ -1,8 +1,8 @@
 import 'dart:ui';
 
 import 'base_entity.dart';
-import 'identifiers/enum/priority.dart';
 import 'identifiers/enum/color.dart';
+import 'identifiers/enum/priority.dart';
 
 class Note extends BaseEntity{
   static String id = BaseEntity.getId;

test/widget_test.dart

@@ -8,7 +8,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
 
-import 'package:progetto_m335_flutter/main.dart';
+import 'package:progetto_m335_flutter/myApp.dart';
 
 void main() {
   testWidgets('Counter increments smoke test', (WidgetTester tester) async {