anchor.diff:  final String flutterCode = r'''
   import 'package:flutter/material.dart';
   
  -final Color darkBlue = Color.fromARGB(255, 18, 32, 47);
  +const Color darkBlue = Color.fromARGB(255, 18, 32, 47);
   
   void main() {
     runApp(MyApp());
  
positive.code: class MyWidget extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return Text('Hello, World!', style: Theme.of(context).textTheme.headline4);
    }
  }
  ''';
  
negative.code:   @override
    Widget build(BuildContext context) {
      return MaterialApp(
        theme: ThemeData.dark().copyWith(
          scaffoldBackgroundColor: darkBlue,
        ),
        debugShowCheckedModeBanner: false,
        home: Scaffold(
          body: Center(
  