Report Flutter framework feature flags

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Features
 
 - Add `message` parameter to `captureException()` ([#2882](https://github.com/getsentry/sentry-dart/pull/2882))
+- Report Flutter framework feature flags ([#2991](https://github.com/getsentry/sentry-dart/pull/2991))
 
 ## 9.0.0
 

flutter/lib/src/integrations/flutter_framework_feature_flag_integration.dart

@@ -0,0 +1,42 @@
+import 'dart:async';
+
+import 'package:flutter/foundation.dart';
+import 'package:sentry/sentry.dart';
+
+const _featureFlag = 'FLUTTER_ENABLED_FEATURE_FLAGS';
+
+// The Flutter framework feature flag works like this:
+// An enabled (experimental) feature gets added to the `FLUTTER_ENABLED_FEATURE_FLAGS`
+// dart define. Being in there means the feature is enabled, the feature is disabled
+// if it's not in there.
+// As a result, we also don't know the whole list of flags, but only the active ones.
+//
+// See https://github.com/flutter/flutter/pull/168437
+class FlutterFrameworkFeatureFlagIntegration
+    extends Integration<SentryOptions> {
+  final String flags;
+
+  FlutterFrameworkFeatureFlagIntegration({
+    @visibleForTesting this.flags = const String.fromEnvironment(_featureFlag),
+  });
+
+  @override
+  FutureOr<void> call(Hub hub, SentryOptions options) {
+    final enabledFeatureFlags = flags.split(',');
+
+    for (final featureFlag in enabledFeatureFlags) {
+      Sentry.addFeatureFlag(featureFlag, true);
+    }
+    options.sdk.addIntegration('FlutterFrameworkFeatureFlagIntegration');
+  }
+}
+
+extension FlutterFrameworkFeatureFlagIntegrationX
+    on List<Integration<SentryOptions>> {
+  /// For better tree-shake-ability we only add the integration if any feature flag is enabled.
+  void addFlutterFrameworkFeatureFlagIntegration() {
+    if (const bool.hasEnvironment(_featureFlag)) {
+      add(FlutterFrameworkFeatureFlagIntegration());
+    }
+  }
+}

flutter/lib/src/sentry_flutter.dart

@@ -18,6 +18,7 @@ import 'file_system_transport.dart';
 import 'flutter_exception_type_identifier.dart';
 import 'frame_callback_handler.dart';
 import 'integrations/connectivity/connectivity_integration.dart';
+import 'integrations/flutter_framework_feature_flag_integration.dart';
 import 'integrations/frames_tracking_integration.dart';
 import 'integrations/integrations.dart';
 import 'integrations/native_app_start_handler.dart';
@@ -172,6 +173,9 @@ mixin SentryFlutter {
     // This tracks Flutter application events, such as lifecycle events.
     integrations.add(WidgetsBindingIntegration());
 
+    // Adds Flutter framework feature flags.
+    integrations.addFlutterFrameworkFeatureFlagIntegration();
+
     // The ordering here matters, as we'd like to first start the native integration.
     // That allow us to send events to the network and then the Flutter integrations.
     final native = _native;

flutter/test/integrations/flutter_framework_feature_flag_integration_test.dart

@@ -0,0 +1,28 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:sentry_flutter/src/integrations/flutter_framework_feature_flag_integration.dart';
+
+import '../mocks.dart';
+import '../mocks.mocks.dart';
+
+void main() {
+  group(FlutterFrameworkFeatureFlagIntegration, () {
+    test('adds sdk integration', () {
+      final options = defaultTestOptions();
+      FlutterFrameworkFeatureFlagIntegration(flags: 'foo,bar,baz')
+          .call(MockHub(), options);
+
+      expect(
+          options.sdk.integrations
+              .contains('FlutterFrameworkFeatureFlagIntegration'),
+          true);
+    });
+
+    test('adds feature flags', () {
+      final options = defaultTestOptions();
+      FlutterFrameworkFeatureFlagIntegration(flags: 'foo,bar,baz')
+          .call(MockHub(), options);
+
+      // TODO what expect to write here?
+    });
+  });
+}