Remove the Flutter pub root directory if it was accidentally cached (#6911)

packages/devtools_app/lib/src/shared/preferences.dart

diff --git a/packages/devtools_app/lib/src/shared/preferences.dart b/packages/devtools_app/lib/src/shared/preferences.dart
index 45acca3..1cd671b 100644
--- a/packages/devtools_app/lib/src/shared/preferences.dart
+++ b/packages/devtools_app/lib/src/shared/preferences.dart
@@ -159,6 +159,7 @@
   static const _customPubRootDirectoriesStoragePrefix =
       'inspector.customPubRootDirectories';
   String? _mainScriptDir;
+  bool _checkedFlutterPubRoot = false;
 
   Future<void> _updateMainScriptRef() async {
     final rootLibUriString =
@@ -252,6 +253,7 @@
 
   @visibleForTesting
   Future<void> handleConnectionToNewService() async {
+    _checkedFlutterPubRoot = false;
     await _updateMainScriptRef();
     await _updateHoverEvalMode();
     await loadPubRootDirectories();
@@ -277,12 +279,30 @@
     final cachedDirectoriesJson =
         await storage.getValue(_customPubRootStorageId());
     if (cachedDirectoriesJson == null) return <String>[];
-
-    return List<String>.from(
+    final cachedDirectories = List<String>.from(
       jsonDecode(cachedDirectoriesJson),
     );
+
+    // Remove the Flutter pub root directory if it was accidentally cached.
+    // See:
+    // - https://github.com/flutter/devtools/issues/6882
+    // - https://github.com/flutter/devtools/issues/6841
+    if (!_checkedFlutterPubRoot && cachedDirectories.any(_isFlutterPubRoot)) {
+      // Set [_checkedFlutterPubRoot] to true to avoid an infinite loop on the
+      // next call to [removePubRootDirectories]:
+      _checkedFlutterPubRoot = true;
+      final flutterPubRootDirectories =
+          cachedDirectories.where(_isFlutterPubRoot).toList();
+      await removePubRootDirectories(flutterPubRootDirectories);
+      cachedDirectories.removeWhere(_isFlutterPubRoot);
+    }
+
+    return cachedDirectories;
   }
 
+  bool _isFlutterPubRoot(String directory) =>
+      directory.endsWith('packages/flutter');
+
   /// As we aren't running from an IDE, we don't know exactly what the pub root
   /// directories are for the current project so we make a best guess based on
   /// the root library for the main isolate.

packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md

diff --git a/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md b/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md
index 59ced0c..cfd2c3f 100644
--- a/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md
+++ b/packages/devtools_app/release_notes/NEXT_RELEASE_NOTES.md
@@ -15,6 +15,7 @@
 ## Inspector updates
 
 * Only cache pub root directories added by the user - [6897](https://github.com/flutter/devtools/pull/6897)
+* Remove Flutter pub root if it was accidently cached - [6911](https://github.com/flutter/devtools/pull/6911)
 
 ## Performance updates
 

packages/devtools_app/test/shared/preferences_controller_test.dart

diff --git a/packages/devtools_app/test/shared/preferences_controller_test.dart b/packages/devtools_app/test/shared/preferences_controller_test.dart
index b7dc518..0235212 100644
--- a/packages/devtools_app/test/shared/preferences_controller_test.dart
+++ b/packages/devtools_app/test/shared/preferences_controller_test.dart
@@ -270,11 +270,8 @@
       test(
         'does not save inferred directory to local cache',
         () async {
-          final cachedDirectoriesJson = await storage
-              .getValue('inspector.customPubRootDirectories_myPackage');
-          final cachedDirectories = List<String>.from(
-            jsonDecode(cachedDirectoriesJson!),
-          );
+          final cachedDirectories =
+              await controller.readCachedPubRootDirectories();
 
           expect(cachedDirectories, isNot(contains('test_dir/fake_app')));
         },
@@ -286,12 +283,8 @@
           await controller.addPubRootDirectories(
             ['test_dir/fake_app/do_not_cache_dir'],
           );
-
-          final cachedDirectoriesJson = await storage
-              .getValue('inspector.customPubRootDirectories_myPackage');
-          final cachedDirectories = List<String>.from(
-            jsonDecode(cachedDirectoriesJson!),
-          );
+          final cachedDirectories =
+              await controller.readCachedPubRootDirectories();
 
           expect(
             cachedDirectories,
@@ -300,6 +293,78 @@
         },
       );
     });
+
+    test('Flutter pub root is removed from cache on app connection', () async {
+      updateMainIsolateRootLibrary('test_dir/fake_app/lib/main.dart');
+      await storage.setValue(
+        'inspector.customPubRootDirectories_myPackage',
+        jsonEncode(
+          [
+            'flutter_dir/flutter/packages/flutter',
+            'test_dir/fake_app/custom_dir1',
+          ],
+        ),
+      );
+      await controller.handleConnectionToNewService();
+      final cachedDirectories = await controller.readCachedPubRootDirectories();
+
+      expect(
+        cachedDirectories,
+        isNot(contains('flutter_dir/flutter/packages/flutter')),
+      );
+      expect(
+        cachedDirectories,
+        contains('test_dir/fake_app/custom_dir1'),
+      );
+    });
+
+    test(
+      'Flutter pub root is removed from cache across multiple app connections',
+      () async {
+        updateMainIsolateRootLibrary('test_dir/fake_app/lib/main.dart');
+        await storage.setValue(
+          'inspector.customPubRootDirectories_myPackage',
+          jsonEncode(
+            [
+              'flutter_dir/flutter/packages/flutter',
+              'test_dir/fake_app/custom_dir1',
+            ],
+          ),
+        );
+        await controller.handleConnectionToNewService();
+        var cachedDirectories = await controller.readCachedPubRootDirectories();
+
+        expect(
+          cachedDirectories,
+          isNot(contains('flutter_dir/flutter/packages/flutter')),
+        );
+        expect(
+          cachedDirectories,
+          contains('test_dir/fake_app/custom_dir1'),
+        );
+
+        await storage.setValue(
+          'inspector.customPubRootDirectories_myPackage',
+          jsonEncode(
+            [
+              'flutter_dir/flutter/packages/flutter',
+              'test_dir/fake_app/custom_dir2',
+            ],
+          ),
+        );
+        await controller.handleConnectionToNewService();
+        cachedDirectories = await controller.readCachedPubRootDirectories();
+
+        expect(
+          cachedDirectories,
+          isNot(contains('flutter_dir/flutter/packages/flutter')),
+        );
+        expect(
+          cachedDirectories,
+          contains('test_dir/fake_app/custom_dir2'),
+        );
+      },
+    );
   });
 
   group('$MemoryPreferencesController', () {