runZoned with zoneValues unavailable during integration_test

[felangel]

Steps to Reproduce

1. Create a basic flutter app which wraps runApp with runZoned and provides a custom zone value:

import 'dart:async';

import 'package:flutter/material.dart';

const zoneKey = Object();

void main() {
  runZoned(
    () => runApp(const MyApp()),
    zoneValues: {zoneKey: 'Hello World'},
  );
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    final zoneValue = Zone.current[zoneKey];
    print('MyApp.build() $zoneValue'); // NULL during integration_test run
    return const MaterialApp();
  }
}

2. Write an integration test:

import 'package:flutter_test/flutter_test.dart';
import 'package:example/main.dart' as app;

void main() {
  group('App', () {
    testWidgets('renders MyApp', (tester) async {
      app.main();
      await tester.pumpAndSettle();
      expect(find.byType(app.MyApp), findsOneWidget);
    });
  });
}

3. Run the integration test flutter test integration_test
4. Observe that the zone value is null within the build method of MyApp

Expected results:

I'd expect the zone value to be available within the build method since runApp was executed within the zone.

Actual results:

The zone value is null within the build method during the integration_test run.

Additional Context

Even when the entire test suite is wrapped in runZoned, the zone values are not available during an integration_test run:

void main() {
  runZoned(() {
    final zoneValue = Zone.current[app.zoneKey];
    print('test.main(), $zoneValue'); // Hello Test
    group('App', () {
      final zoneValue = Zone.current[app.zoneKey];
      print('test.group(), $zoneValue'); // Hello Test
      testWidgets('renders MyApp', (tester) async {
        final zoneValue = Zone.current[app.zoneKey];
        print('test.testWidgets(), $zoneValue'); // null
        app.main();
        await tester.pumpAndSettle();
        expect(find.byType(app.MyApp), findsOneWidget);
      });
    });
  }, zoneValues: {app.zoneKey: 'Hello Test'});
}

It looks like testWidgets runs the body inside a new zone and does not fork the parent zone and inherit the zoneValues.

Related Issues

• Flutter framework does not warn when ensureInitialized is called in a different zone than runApp #94123
• runZoned with zoneValues lost after hot reload #93676

Logs

{"CFBundleName":"zones","DTXcode":"1310","DTSDKName":"iphonesimulator15.0","UILaunchStoryboardName":"LaunchScreen","CFBundleIcons~ipad":{"CFBundlePrimaryIcon":{"CFBundleIconFiles":["AppIcon20x20","AppIcon29x29","AppIcon40x40","AppIcon60x60","AppIcon76x76","AppIcon83.5x83.
5"],"CFBundleIconName":"AppIcon"}},"DTSDKBuild":"19A339","CFBundleDevelopmentRegion":"en","CFBundleVersion":"1","BuildMachineOSBuild":"21A559","DTPlatformName":"iphonesimulator","CFBundlePackageType":"APPL","UIMainStoryboardFile":"Main","CFBundleSupportedPlatforms":["iPho
neSimulator"],"CFBundleShortVersionString":"1.0.0","CFBundleInfoDictionaryVersion":"6.0","CFBundleExecutable":"Runner","DTCompiler":"com.apple.compilers.llvm.clang.1_0","UISupportedInterfaceOrientations~ipad":["UIInterfaceOrientationPortrait","UIInterfaceOrientationPortra
itUpsideDown","UIInterfaceOrientationLandscapeLeft","UIInterfaceOrientationLandscapeRight"],"MinimumOSVersion":"9.0","CFBundleIdentifier":"com.example.zones","UIDeviceFamily":[1,2],"DTPlatformVersion":"15.0","CFBundleSignature":"????","CFBundleIcons":{"CFBundlePrimaryIcon
":{"CFBundleIconFiles":["AppIcon20x20","AppIcon29x29","AppIcon40x40","AppIcon60x60"],"CFBundleIconName":"AppIcon"}},"DTXcodeBuild":"13A1030d","LSRequiresIPhoneOS":true,"UISupportedInterfaceOrientations":["UIInterfaceOrientationPortrait","UIInterfaceOrientationLandscapeLef
t","UIInterfaceOrientationLandscapeRight"],"UIViewControllerBasedStatusBarAppearance":false,"NSBonjourServices":["_dartobservatory._tcp"],"DTPlatformBuild":"19A339","NSLocalNetworkUsageDescription":"Allow Flutter tools on your computer to connect and debug your
application. This prompt will not appear on release builds."}
[   +4 ms] executing: xcrun simctl launch FCB4BE3E-33DA-49FC-A861-F647555D56A9 com.example.zones --enable-dart-profiling --enable-checked-mode --verify-entry-points --observatory-port=0
[ +205 ms] com.example.zones: 51465
[   +1 ms] Waiting for observatory port to be available...
[ +416 ms] Observatory URL on device: http://127.0.0.1:55348/QIoVQ24XVz0=/
[   +9 ms] Caching compiled dill
[  +51 ms] Connecting to service protocol: http://127.0.0.1:55348/QIoVQ24XVz0=/
[ +167 ms] Launching a Dart Developer Service (DDS) instance at http://127.0.0.1:0, connecting to VM service at http://127.0.0.1:55348/QIoVQ24XVz0=/.
[  +95 ms] DDS is listening at http://127.0.0.1:55351/1RcuH9jFcOE=/.
[  +59 ms] Successfully connected to service protocol: http://127.0.0.1:55348/QIoVQ24XVz0=/
[  +26 ms] DevFS: Creating new filesystem on the device (null)
[  +17 ms] DevFS: Created new filesystem on the device (file:///Users/felix/Library/Developer/CoreSimulator/Devices/FCB4BE3E-33DA-49FC-A861-F647555D56A9/data/Containers/Data/Application/42BE9414-534D-477C-ADEB-EDC73F58B7FA/tmp/zonesEyB4Fm/zones/)
[   +2 ms] Updating assets
[  +63 ms] Syncing files to device iPhone 13...
[   +2 ms] <- reset
[        ] Compiling dart to kernel with 0 updated files
[   +3 ms] <- recompile package:zones/main.dart 7fd16ad6-36b9-4ac5-99dd-f42726cef603
[        ] <- 7fd16ad6-36b9-4ac5-99dd-f42726cef603
[  +64 ms] Updating files.
[        ] DevFS: Sync finished
[        ] Syncing files to device iPhone 13... (completed in 71ms)
[        ] Synced 0.0MB.
[   +1 ms] <- accept
[   +6 ms] Connected to _flutterView/0x7fb30a810c20.
[   +3 ms] Flutter run key commands.
[   +1 ms] r Hot reload. 🔥🔥🔥
[        ] R Hot restart.
[        ] h List all available interactive commands.
[        ] d Detach (terminate "flutter run" but leave application running).
[        ] c Clear the screen
[        ] q Quit (terminate the application on the device).
[        ] 💪 Running with sound null safety 💪
[        ] An Observatory debugger and profiler on iPhone 13 is available at: http://127.0.0.1:55351/1RcuH9jFcOE=/
[ +490 ms] The Flutter DevTools debugger and profiler on iPhone 13 is available at: http://127.0.0.1:9102?uri=http://127.0.0.1:55351/1RcuH9jFcOE=/
[+4486 ms] Skipping target: gen_localizations
[        ] Skipping target: gen_dart_plugin_registrant
[        ] Skipping target: _composite
[        ] complete
[        ] Performing hot reload...
[  +11 ms] Scanned through 528 files in 6ms
[        ] Syncing files to device iPhone 13...
[        ] Compiling dart to kernel with 0 updated files
[        ] <- recompile package:zones/main.dart 564d0ee5-dbd9-4020-bfeb-4217c387483f
[        ] <- 564d0ee5-dbd9-4020-bfeb-4217c387483f
[   +6 ms] Updating files.
[   +2 ms] DevFS: Sync finished
[        ] Syncing files to device iPhone 13... (completed in 9ms)
[        ] Synced 0.0MB.
[  +11 ms] Reassembling application
[  +39 ms] Hot reload performed in 67ms.
[   +1 ms] Performing hot reload... (completed in 73ms)
[        ] Reloaded 0 libraries in 78ms.

No issues found! (ran in 1.9s)

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    • macOS (desktop)    • macos                                • darwin-x64     • macOS 12.0.1 21A559 darwin-x64
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• No issues found!

[danagbemava-nc]

Hi @felangel, you appear to be on an older version of beta.

Can you upgrade to the latest version to see if you still experience this issue?

Thank you

[felangel]

Hey @danagbemava-nc sorry for the delayed response.

I just verified that I'm seeing the same result on the master channel:

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel master, 2.9.0-1.0.pre.498, on macOS 12.0.1 21A559 darwin-x64, locale en-US)
[✓] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
[✓] Xcode - develop for iOS and macOS (Xcode 13.1)
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[✓] VS Code (version 1.64.0-insider)
[✓] Connected device (3 available)
    ! Error: Felix’s iPhone is not connected. Xcode will continue when Felix’s iPhone is connected. (code -13)
[✓] HTTP Host Availability

• No issues found!

[Hixie]

I suspect the same would happen in a unit test (with flutter_test). The problem is likely that Zone.current is not the zone you are expecting, because integration_test and flutter_test make heavy use of zones of their own. You might be able to find the data by walking up the chain of Zones until you get to the one you expect.

(In general I personaly would recommend against using Zones, they are a never-ending source of pain in my experience. Better to just inject an InheritedWidget and/or pass the data via arguments.)

[felangel]

I suspect the same would happen in a unit test (with flutter_test). The problem is likely that Zone.current is not the zone you are expecting, because integration_test and flutter_test make heavy use of zones of their own. You might be able to find the data by walking up the chain of Zones until you get to the one you expect.

Shouldn't integration_test and flutter_test respect the current zone they are in and fork it (preserving the zone values)?

(In general I personaly would recommend against using Zones, they are a never-ending source of pain in my experience. Better to just inject an InheritedWidget and/or pass the data via arguments.)

This is not feasible because this is an issue in the context of a pure Dart package being used within a Flutter application. The implementation is pure Dart.

[danagbemava-nc]

Reproducible using sample and steps in #96939 (comment).

code samples

main.dart

import 'dart:async';

import 'package:flutter/material.dart';

const zoneKey = Object();

void main() {
  runZoned(
    () => runApp(const MyApp()),
    zoneValues: {zoneKey: 'Hello World'},
  );
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    final zoneValue = Zone.current[zoneKey];
    
    // added to make print output visible
    print(
        '+============================+\nMyApp.build() $zoneValue\n+============================+'); // NULL during integration_test run
    return const MaterialApp();
  }
}

integration_test/app_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:it/main.dart' as app;

void main() {
  group('App', () {
    testWidgets('renders MyApp', (tester) async {
      app.main();
      await tester.pumpAndSettle();
      expect(find.byType(app.MyApp), findsOneWidget);
    });
  });
}

logs

run_log.txt
test_log.txt

flutter doctor -v

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[☠] IntelliJ IDEA Community Edition (the doctor check crashed)
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    ✗ FormatException: Unexpected extension byte (at offset 5)
    • #0      _Utf8Decoder.convertSingle (dart:convert-patch/convert_patch.dart:1789:7)
      #1      Utf8Decoder.convert (dart:convert/utf.dart:318:42)
      #2      InputStream.readString (package:archive/src/util/input_stream.dart:207:30)
      #3      new ZipDirectory.read (package:archive/src/zip/zip_directory.dart:40:30)
      #4      ZipDecoder.decodeBuffer (package:archive/src/zip_decoder.dart:19:30)
      #5      ZipDecoder.decodeBytes (package:archive/src/zip_decoder.dart:14:12)
      #6      IntelliJPlugins._findPluginXml (package:flutter_tools/src/intellij/intellij.dart:130:44)
      #7      IntelliJPlugins._readPackageVersion (package:flutter_tools/src/intellij/intellij.dart:141:40)
      #8      IntelliJPlugins.validatePackage (package:flutter_tools/src/intellij/intellij.dart:63:35)
      #9      IntelliJValidator.validate (package:flutter_tools/src/intellij/intellij_validator.dart:103:15)
      #10     asyncGuard.<anonymous closure> (package:flutter_tools/src/base/async_guard.dart:111:32)
      #11     asyncGuard.<anonymous closure> (package:flutter_tools/src/base/async_guard.dart:109:18)
      #12     _rootRun (dart:async/zone.dart:1428:13)
      #13     _CustomZone.run (dart:async/zone.dart:1328:19)
      #14     _runZoned (dart:async/zone.dart:1863:10)
      #15     runZonedGuarded (dart:async/zone.dart:1851:12)
      #16     runZoned (dart:async/zone.dart:1782:12)
      #17     asyncGuard (package:flutter_tools/src/base/async_guard.dart:109:3)
      #18     Doctor.startValidatorTasks (package:flutter_tools/src/doctor.dart:197:9)
      #19     Doctor.diagnose (package:flutter_tools/src/doctor.dart:301:47)
      #20     DoctorCommand.runCommand (package:flutter_tools/src/commands/doctor.dart:53:47)
      #21     FlutterCommand.verifyThenRunCommand (package:flutter_tools/src/runner/flutter_command.dart:1290:12)
      <asynchronous suspension>
      #22     FlutterCommand.run.<anonymous closure> (package:flutter_tools/src/runner/flutter_command.dart:1140:27)
      <asynchronous suspension>
      #23     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:150:19)
      <asynchronous suspension>
      #24     CommandRunner.runCommand (package:args/command_runner.dart:209:13)
      <asynchronous suspension>
      #25     FlutterCommandRunner.runCommand.<anonymous closure> (package:flutter_tools/src/runner/flutter_command_runner.dart:288:9)
      <asynchronous suspension>
      #26     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:150:19)
      <asynchronous suspension>
      #27     FlutterCommandRunner.runCommand (package:flutter_tools/src/runner/flutter_command_runner.dart:236:5)
      <asynchronous suspension>
      #28     run.<anonymous closure>.<anonymous closure> (package:flutter_tools/runner.dart:62:9)
      <asynchronous suspension>
      #29     AppContext.run.<anonymous closure> (package:flutter_tools/src/base/context.dart:150:19)
      <asynchronous suspension>
      #30     main (package:flutter_tools/executable.dart:94:3)
      <asynchronous suspension>


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