Testing taking screenshots in GitHub Actions.

See Notion > Integration Testing

Following these articles

• Take screenshot during Flutter integration tests - DEV Community
• Flutter automated screenshot testing using the integration_test package | Codemagic Blog

And running flutter drive --driver=integration_test/screenshot_test_driver.dart --target=integration_test/screenshot_test.dart -d <iphone_emulator_id>

gives:

flutter: 'package:flutter/src/foundation/binding.dart':
Failed assertion: line 55 pos 12:
flutter: '!_debugInitialized': is not true.

Importing flutter_driver

flutter_driver:
    sdk: flutter

And adding enableFlutterDriverExtension(); as the first line of main() in screenshot_test_driver.dart

gives:

../../SDKs/flutter/packages/flutter/lib/src/cupertino/bottom_tab_bar.dart:5:8: Error: Not found: 'dart:ui'
import 'dart:ui' show ImageFilter;
       ^
../../SDKs/flutter/packages/flutter/lib/src/cupertino/colors.dart:5:8: Error: Not found: 'dart:ui'
import 'dart:ui' show Color, Brightness;
       ^
...

Updating code to match the latest instructions at: https://github.com/flutter/flutter/tree/master/packages/integration_test

Gives the error described in: flutter/flutter#91668

Using the workaround described in the issue, ie.

updating flutter/packages/integration_test/ios/Classes/IntegrationTestPlugin.m

by adding a body to:

+ (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar> *)registrar {

to make it:

+ (void)registerWithRegistrar:(NSObject<FlutterPluginRegistrar> *)registrar {
    [[IntegrationTestPlugin instance] setupChannels:registrar.messenger];
}

And screenshots now work.

flutter drive \                                   
  --driver=test_driver/integration_test.dart \
  --target=integration_test/screenshot_test.dart

Saving the image data in the integration test allows us to use:

flutter test integration_test/screenshot_test.dart

And remove the driver code.