listviews_test.dart is failing with vm_service 9.4.0

[elliette]

Before vm_service was at 9.3.0, and the test was passing. Upgraded to 9.4.0:
> vm_service 9.4.0 (was 9.3.0)

Running the test now fails:

dart test test/listviews_test.dart --no-retry --chain-stack-traces
Building package executable... (5.6s)
Built test:test.
00:15 +0 -1: _flutter.listViews [E]
  Expected: {
              'views': [
                {
                  'id': '1',
                  'isolate': {
                    'type': '@Isolate',
                    'id': '1',
                    'number': '1',
                    'name': 'main()',
                    'isSystemIsolate': false,
                    'isolateGroupId': ''
                  }
                }
              ]
            }
    Actual: {
              'views': [
                {
                  'id': '1',
                  'isolate': {
                    'type': '@Isolate',
                    'id': '1',
                    'number': '1',
                    'name': 'main()',
                    'isSystemIsolate': false,
                    'isolateGroupId': null
                  }
                }
              ]
            }
     Which: at location ['views'][0]['isolate']['isolateGroupId'] is <null> instead of ''

  package:test_api               expect
  test/listviews_test.dart 38:5  main.<fn>

[elliette]

Looks like this might be related to https://dart-review.googlesource.com/c/sdk/+/257265?

Adding @liamappelbe @bkonyi for context. This is the test that is failing: https://github.com/dart-lang/webdev/blob/master/dwds/test/listviews_test.dart

Thanks!

[annagrin]

I wonder if changing final StreamController<Map<String, Object>> _requestController; in dwds_vm_client

webdev/dwds/lib/src/dwds_vm_client.dart

Line 46 in 490d6a0

final requestController = StreamController<Map<String, Object>>();

and

webdev/dwds/lib/src/dwds_vm_client.dart

Line 46 in 490d6a0

final requestController = StreamController<Map<String, Object>>();

to StreamController<Map<String, Object?>> _requestController; would help

I believe this would also allow us to remove extra map creation on every VM service request here, which can be saving time:

webdev/dwds/lib/src/dwds_vm_client.dart

Line 58 in 490d6a0

requestController.sink.add(Map<String, Object>.from(jsonDecode(request)));

[annagrin]

Ignore my previous comment, the change suggested did not help.

Found the reason for the test failure - we set the isolateGroupId to null in dwds but IsolateRef._fromJson converts it to an empty string during parsing:

 IsolateRef._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
    id = json['id'] ?? '';
    number = json['number'] ?? '';
    name = json['name'] ?? '';
    isSystemIsolate = json['isSystemIsolate'] ?? false;
    isolateGroupId = json['isolateGroupId'] ?? ''; // This line

@bkonyi Is this intentional? This causes the isolate we return in getVm to be different from the isolate returned by the listViews service extension. If this is intentional behavior of the vm, then we can make it consistent in dwds by setting the isolateGroupId to an empty string on isolate ref creation:

webdev/dwds/lib/src/debugging/inspector.dart

Line 125 in ef52eda

isSystemIsolate: isolate.isSystemIsolate,

and/or

webdev/dwds/lib/src/debugging/inspector.dart

Line 141 in ef52eda

final isolate = Isolate(

[liamappelbe]

Yeah, I have a CL to change the codegen for toJson and _fromJson to be consistent: https://dart-review.googlesource.com/c/sdk/+/258100