To make the test more realistic and thorough, consider using one of the actual old cache names that the cleanup worker is designed to remove, such as flutter-app-cache. This would not only test the unregistration of the service worker but also implicitly test the cache deletion logic, making the test more robust.

  const CACHE_NAME = 'flutter-app-cache';

fixed

The comment 'default Flutter service worker resolves immediately' is a bit vague. It would be clearer to state that service worker registration is now disabled in flutter.js and this method is a stub that no longer performs any action, other than warning about the deprecation.

   * Disables service worker registration from flutter.js. This is now a no-op,
   * and a warning will be logged if any `settings` are provided.
   * @param {import("./types").ServiceWorkerSettings} settings Service worker settings
   * @returns {Promise<void>} that resolves immediately
   */

fixed!

This new service worker implementation is static and does not require any resource map injection. However, the Dart code that generates this service worker in packages/flutter_tools/lib/src/web/file_generators/flutter_service_worker_js.dart still contains logic to replace $$RESOURCES_MAP and $$CORE_LIST placeholders. This logic is now dead code.

While the file containing the generator is not part of this PR, it would be good to simplify generateServiceWorker function and the call site in packages/flutter_tools/lib/src/build_system/targets/web.dart to remove the unused parameters and resource map computation as part of this change or in a follow-up PR to improve maintainability.

@gemini-code-assist can you generate a diff for what you are suggesting?

Thanks for the follow-up! My previous comment highlighted that the new flutter_service_worker.js is static and no longer uses the $$RESOURCES_MAP and $$CORE_LIST placeholders. While this PR correctly updates the flutter_service_worker.js file itself, the logic that generates this file in packages/flutter_tools/lib/src/web/file_generators/flutter_service_worker_js.dart and its call site in packages/flutter_tools/lib/src/build_system/targets/web.dart still contain code to compute and pass these unused parameters.

Since those generator files are not part of this specific pull request, I cannot provide a committable diff directly for them. However, for a follow-up PR, here are the suggested changes to remove that dead code:

1. packages/flutter_tools/lib/src/web/file_generators/flutter_service_worker_js.dart

// Old function signature and body:
// String generateServiceWorker({
//   required Map<String, String> resourcesMap,
//   required List<String> coreList,
// }) {
//   // ... existing logic that uses resourcesMap and coreList to build the old service worker content ...
// }

// New function signature and body:
String generateServiceWorker() {
  return '''
'use strict';

const OLD_CACHE_NAMES = ['flutter-app-manifest', 'flutter-app-cache', 'flutter-temp-cache'];

self.addEventListener('install', () => {
  self.skipWaiting();
  console.log('Deprecated service worker installed. It will not be used.');
});

// remove old caches and unregister the service worker
self.addEventListener('activate', (event) => {
  event.waitUntil(
    (async () => {
      try {
        const deletePromises = OLD_CACHE_NAMES.map((key) => self.caches.delete(key));
        await Promise.all(deletePromises);
      } catch (e) {
        console.warn('Failed to delete old service worker caches:', e);
      }

      try {
        await self.registration.unregister();
      } catch (e) {
        console.warn('Failed to unregister service worker:', e);
      }

      try {
        const clients = await self.clients.matchAll({
          type: 'window',
          includeUncontrolled: true,
        });
        // Reload clients to ensure they are not using the old service worker.
        clients.forEach((client) => {
          if (client.url && 'navigate' in client) {
            client.navigate(client.url);
          }
        });
      } catch (e) {
        console.warn('Failed to navigate service worker clients:', e);
      }
    })()
  );
});
''';
}

2. packages/flutter_tools/lib/src/build_system/targets/web.dart

// Old call site (inside a build step or function):
// final Map<String, String> resourcesMap = <String, String>{ /* ... compute ... */ };
// final List<String> coreList = <String>[ /* ... compute ... */ ];
// final String serviceWorkerContent = generateServiceWorker(
//   resourcesMap: resourcesMap,
//   coreList: coreList,
// );

// New call site:
final String serviceWorkerContent = generateServiceWorker();

These changes would remove the now-unused parameters and the logic to compute them, aligning the generator with the new static service worker content.

@SydneyBao Gemini is right that we should update that function, but the diff it produced isn't right 😅

We should do something like this:

String generateServiceWorker(
  String fileGeneratorsPath, {
  required ServiceWorkerStrategy serviceWorkerStrategy,
}) {
  if (serviceWorkerStrategy == ServiceWorkerStrategy.none) {
    return '';
  }

  final String flutterServiceWorkerJsPath = globals.localFileSystem.path.join(
    fileGeneratorsPath,
    'js',
    'flutter_service_worker.js',
  );
  return globals.localFileSystem
      .file(flutterServiceWorkerJsPath)
      .readAsStringSync();
}

Nice catch! Fixed it!

new line

done!

new line

done!

These 2 are now repeated twice.

Can't believe I didn't catch that. Thank you!

These 2 didn't exist before. They seem unrelated to the service worker, is there a reason they were added?

Must've been added when I copied my code from an older branch. They've been removed. Thank you!

These 2 aren't supposed to be run as part of this shard. They are run separately as you can see here:

removed!

new line

done!