address review feedback: clarify comment and fix test file ordering

Author: rishika0212

packages/devtools_app_shared/lib/src/service/isolate_manager.dart

@@ -181,8 +181,9 @@ final class IsolateManager with DisposerMixin {
           (_shouldReselectMainIsolate ||
               _selectedIsolate.value == null ||
               _selectedIsolate.value == previousMain)) {
-        // If the previous main exited and returned (hot restart) or we were
-        // following the previous main, follow the newly computed main isolate.
+        // If the previous main exited and returned (hot restart), or if the
+        // selected isolate was previously the main isolate, update selection to
+        // the newly computed main isolate.
         _shouldReselectMainIsolate = false;
         _setSelectedIsolate(_mainIsolate.value);
       }

packages/devtools_app_shared/test/service/isolate_manager_test.dart

@@ -8,81 +8,6 @@ import 'package:devtools_app_shared/src/service/isolate_manager.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:vm_service/vm_service.dart';
 
-/// Minimal fake VmService for IsolateManager tests.
-class _FakeVmService extends Fake implements VmService {
-  _FakeVmService(this.isolates);
-
-  /// Map of isolate id -> Isolate to return from getIsolate().
-  final Map<String, Isolate> isolates;
-
-  final _isolateEventController = StreamController<Event>.broadcast();
-
-  @override
-  Stream<Event> get onIsolateEvent => _isolateEventController.stream;
-
-  @override
-  Stream<Event> get onDebugEvent => const Stream.empty();
-
-  @override
-  Future<Isolate> getIsolate(String isolateId) async {
-    return isolates[isolateId] ??
-        Isolate.parse({
-          'id': isolateId,
-          'runnable': true,
-          'extensionRPCs': <String>[],
-        })!;
-  }
-
-  @override
-  Future<Success> resume(String isolateId, {String? step, int? frameIndex}) =>
-      Future.value(Success());
-
-  Future<void> emitIsolateStart(IsolateRef isolateRef) async {
-    _isolateEventController.add(
-      Event.parse({
-        'type': 'Event',
-        'kind': EventKind.kIsolateStart,
-        'isolate': {
-          'type': '@Isolate',
-          'id': isolateRef.id,
-          'name': isolateRef.name,
-          'isSystemIsolate': isolateRef.isSystemIsolate,
-        },
-      })!,
-    );
-    await Future<void>.delayed(Duration.zero);
-  }
-
-  @override
-  Future<void> dispose() async {
-    await _isolateEventController.close();
-  }
-}
-
-/// Creates a minimal runnable [Isolate] for a given [IsolateRef].
-Isolate _makeIsolate(IsolateRef ref, {String? rootLibraryUri}) {
-  final json = <String, Object?>{
-    'id': ref.id,
-    'name': ref.name,
-    'type': '@Isolate',
-    'runnable': true,
-    'extensionRPCs': <String>[],
-    if (rootLibraryUri != null)
-      'rootLib': {
-        'type': '@Library',
-        'id': 'libraries/0',
-        'uri': rootLibraryUri,
-      },
-  };
-
-  return Isolate.parse(json)!;
-}
-
-/// Creates an [IsolateRef] with the given name and id.
-IsolateRef _makeRef(String name, String id) {
-  return IsolateRef.parse({'name': name, 'id': id, 'isSystemIsolate': false})!;
-}
-
 void main() {
   group('IsolateManager._computeMainIsolate', () {
     late IsolateManager manager;
@@ -115,9 +40,9 @@ void main() {
         final vmServiceRef = _makeRef('vm-service', 'isolates/3');
 
         final fakeService = _FakeVmService({
-          'isolates/1': _makeIsolate(testRunnerRef),
-          'isolates/2': _makeIsolate(testSuiteRef),
-          'isolates/3': _makeIsolate(vmServiceRef),
+          testRunnerRef.id!: _makeIsolate(testRunnerRef),
+          testSuiteRef.id!: _makeIsolate(testSuiteRef),
+          vmServiceRef.id!: _makeIsolate(vmServiceRef),
         });
         fakeServices.add(fakeService);
 
@@ -143,8 +68,8 @@ void main() {
       final vmServiceRef = _makeRef('vm-service', 'isolates/2');
 
       final fakeService = _FakeVmService({
-        'isolates/1': _makeIsolate(mainRef),
-        'isolates/2': _makeIsolate(vmServiceRef),
+        mainRef.id!: _makeIsolate(mainRef),
+        vmServiceRef.id!: _makeIsolate(vmServiceRef),
       });
       fakeServices.add(fakeService);
 
@@ -162,7 +87,7 @@ void main() {
       final scriptRef = _makeRef('foo.dart:main()', 'isolates/1');
 
       final fakeService = _FakeVmService({
-        'isolates/1': _makeIsolate(scriptRef),
+        scriptRef.id!: _makeIsolate(scriptRef),
       });
       fakeServices.add(fakeService);
 
@@ -183,15 +108,15 @@ void main() {
         final vmServiceRef = _makeRef('vm-service', 'isolates/3');
 
         final fakeService = _FakeVmService({
-          'isolates/1': _makeIsolate(
+          testRunnerRef.id!: _makeIsolate(
             testRunnerRef,
             rootLibraryUri: 'file:///tmp/dart_test.kernel.abcd/test.dart',
           ),
-          'isolates/2': _makeIsolate(
+          userTestRef.id!: _makeIsolate(
             userTestRef,
             rootLibraryUri: 'package:my_app/foo_test.dart',
           ),
-          'isolates/3': _makeIsolate(
+          vmServiceRef.id!: _makeIsolate(
             vmServiceRef,
             rootLibraryUri: 'dart:developer',
           ),
@@ -223,8 +148,8 @@ void main() {
         );
 
         final fakeService = _FakeVmService({
-          'isolates/1': _makeIsolate(testRunnerRef),
-          'isolates/2': _makeIsolate(testSuiteRef),
+          testRunnerRef.id!: _makeIsolate(testRunnerRef),
+          testSuiteRef.id!: _makeIsolate(testSuiteRef),
         });
         fakeServices.add(fakeService);
 
@@ -250,3 +175,78 @@ void main() {
     );
   });
 }
+
+/// Minimal fake VmService for IsolateManager tests.
+class _FakeVmService extends Fake implements VmService {
+  _FakeVmService(this.isolates);
+
+  /// Map of isolate id -> Isolate to return from getIsolate().
+  final Map<String, Isolate> isolates;
+
+  final _isolateEventController = StreamController<Event>.broadcast();
+
+  @override
+  Stream<Event> get onIsolateEvent => _isolateEventController.stream;
+
+  @override
+  Stream<Event> get onDebugEvent => const Stream.empty();
+
+  @override
+  Future<Isolate> getIsolate(String isolateId) async {
+    return isolates[isolateId] ??
+        Isolate.parse({
+          'id': isolateId,
+          'runnable': true,
+          'extensionRPCs': <String>[],
+        })!;
+  }
+
+  @override
+  Future<Success> resume(String isolateId, {String? step, int? frameIndex}) =>
+      Future.value(Success());
+
+  Future<void> emitIsolateStart(IsolateRef isolateRef) async {
+    _isolateEventController.add(
+      Event.parse({
+        'type': 'Event',
+        'kind': EventKind.kIsolateStart,
+        'isolate': {
+          'type': '@Isolate',
+          'id': isolateRef.id,
+          'name': isolateRef.name,
+          'isSystemIsolate': isolateRef.isSystemIsolate,
+        },
+      })!,
+    );
+    await Future<void>.delayed(Duration.zero);
+  }
+
+  @override
+  Future<void> dispose() async {
+    await _isolateEventController.close();
+  }
+}
+
+/// Creates a minimal runnable [Isolate] for a given [IsolateRef].
+Isolate _makeIsolate(IsolateRef ref, {String? rootLibraryUri}) {
+  final json = <String, Object?>{
+    'id': ref.id,
+    'name': ref.name,
+    'type': '@Isolate',
+    'runnable': true,
+    'extensionRPCs': <String>[],
+    if (rootLibraryUri != null)
+      'rootLib': {
+        'type': '@Library',
+        'id': 'libraries/0',
+        'uri': rootLibraryUri,
+      },
+  };
+
+  return Isolate.parse(json)!;
+}
+
+/// Creates an [IsolateRef] with the given name and id.
+IsolateRef _makeRef(String name, String id) {
+  return IsolateRef.parse({'name': name, 'id': id, 'isSystemIsolate': false})!;
+}