应该如何使用 flutter_web_test 包在 flutter_web 项目上运行单元测试？

Question

I have been exploring the flutter web for a while, everything is fine.

But I have problems in creating unit test (StatelessWidget test for example) for flutter_web components.

I have discover that there is a packages called flutter_web_test but it seems didn't work well.

test code as follow:

I have install test packages used by flutter_web demo projects: flutter_web_test

// import fluter
import 'package:flutter_web_test/flutter_web_test.dart';
// a stateless widget is imported
import 'package:ies2.pms/views/main.dart';

void main() {
  testWidgets(
    'test whether ',
    (WidgetTester tester) async {
      // very simple code, create widget in test
      await tester.pumpWidget(CYFCustomView(name: 'aaa'));
      print('aaa');
    },
  );
}

Then I start running with flutter test

Then I have received following errors:

Failed to load test harness. Are you missing a dependency on flutter_test?


00:05 +0: loading /Users/yifan.chen/ByteDanceIES/pms/test/main_test.dart                                                                               Unhandled exception:
FileSystemException(uri=org-dartlang-untranslatable-uri:package%3Aflutter_test%2Fflutter_test.dart; message=StandardFileSystem only supports file:* and
data:* URIs)
#0      StandardFileSystem.entityForUri (package:front_end/src/api_prototype/standard_file_system.dart:33:7)
#1      asFileUri (package:vm/kernel_front_end.dart:601:37)
<asynchronous suspension>
#2      FrontendCompiler._outputDependenciesDelta (package:vm/frontend_server.dart:401:39)
<asynchronous suspension>
#3      FrontendCompiler.compile (package:vm/frontend_server.dart:375:13)
<asynchronous suspension>
#4      _FlutterFrontendCompiler.compile (package:frontend_server/server.dart:31:22)
<asynchronous suspension>
#5      listenAndCompile.<anonymous closure> (package:vm/frontend_server.dart:736:26)
<asynchronous suspension>
#6      _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
#7      _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#8      _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#9      _SinkTransformerStreamSubscription._add (dart:async/stream_transformers.dart:68:11)
#10     _EventSinkWrapper.add (dart:async/stream_transformers.dart:15:11)
#11     _StringAdapterSink.add (dart:convert/string_conversion.dart:236:11)
#12     _LineSplitterSink._addLines (dart:convert/line_splitter.dart:150:13)
#13     _LineSplitterSink.addSlice (dart:convert/line_splitter.dart:125:5)
#14     StringConversionSinkMixin.add (dart:convert/string_conversion.dart:163:5)
#15     _SinkTransformerStreamSubscription._handleData (dart:async/stream_transformers.dart:120:24)
#16     _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
#17     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#18     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#19     _SinkTransformerStreamSubscription._add (dart:async/stream_transformers.dart:68:11)
#20     _EventSinkWrapper.add (dart:async/stream_transformers.dart:15:11)
#21     _StringAdapterSink.add (dart:convert/string_conversion.dart:236:11)
#22     _StringAdapterSink.addSlice (dart:convert/string_conversion.dart:241:7)
#23     _Utf8ConversionSink.addSlice (dart:convert/string_conversion.dart:312:20)
#24     _Utf8ConversionSink.add (dart:convert/string_conversion.dart:305:5)
#25     _ConverterStreamEventSink.add (dart:convert/chunked_conversion.dart:72:18)
#26     _SinkTransformerStreamSubscription._handleData (dart:async/stream_transformers.dart:120:24)
#27     _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
#28     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#29     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#30     _SyncStreamController._sendData (dart:async/stream_controller.dart:764:19)
#31     _StreamController._add (dart:async/stream_controller.dart:640:7)
#32     _StreamController.add (dart:async/stream_controller.dart:586:5)
#33     _Socket._onData (dart:io-patch/socket_patch.dart:1786:41)
#34     _RootZone.runUnaryGuarded (dart:async/zone.dart:1314:10)
#35     _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#36     _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#37     _SyncStreamController._sendData (dart:async/stream_controller.dart:764:19)
#38     _StreamController._add (dart:async/stream_controller.dart:640:7)
#39     _StreamController.add (dart:async/stream_controller.dart:586:5)
#40     new _RawSocket.<anonymous closure> (dart:io-patch/socket_patch.dart:1335:33)
#41     _NativeSocket.issueReadEvent.issue (dart:io-patch/socket_patch.dart:856:14)
#42     _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#43     _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
#44     _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:116:13)
#45     _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:173:5)
00:05 +0 -1: loading /Users/yifan.chen/ByteDanceIES/pms/test/main_test.dart [E]      

I can't find any solutions in Stackoverflow. And flutter_web currently haven't open issues yet. I have only discovered an issue in flutter, saying that flutter test is not supported for flutter_web project.

How should I run unit test on flutter_web project ? They have built flutter_web_test package, so it is supposed to be functional.

Answer 1

you shoukd move to flutter 1.9, flutter_web is deprecrated https://flutter.dev/web , the shorter way is update flutter to 1.9, create a new fresh project and activate web on it: flutter run -d chrome now you can build with flutter build web . I hope it solves your problems.