Report feature flags enabled if the flutter tool crashes on a bot. (flutter#171304)

Towards flutter#38901.

Next PR will also add feature flags to `flutter doctor`.

Author: matanlurey

packages/flutter_tools/lib/runner.dart

@@ -119,6 +119,7 @@ Future<int> run(
             reportCrashes!,
             getVersion,
             shutdownHooks,
+            featureFlags: featureFlags,
           );
         }
       },
@@ -136,6 +137,7 @@ Future<int> run(
           reportCrashes!,
           getVersion,
           shutdownHooks,
+          featureFlags: featureFlags,
         );
       },
     )!;
@@ -149,8 +151,9 @@ Future<int> _handleToolError(
   List<String> args,
   bool reportCrashes,
   String Function() getFlutterVersion,
-  ShutdownHooks shutdownHooks,
-) async {
+  ShutdownHooks shutdownHooks, {
+  required FeatureFlags featureFlags,
+}) async {
   if (error is UsageException) {
     globals.printError('${error.message}\n');
     globals.printError(
@@ -187,11 +190,16 @@ Future<int> _handleToolError(
   } else {
     // We've crashed; emit a log report.
     globals.stdio.stderrWrite('\n');
-
     if (!reportCrashes) {
       // Print the stack trace on the bots - don't write a crash report.
       globals.stdio.stderrWrite('$error\n');
       globals.stdio.stderrWrite('$stackTrace\n');
+
+      final String featureFlagsEnabled = allConfigurableFeatures
+          .where(featureFlags.isEnabled)
+          .map((Feature f) => f.configSetting)
+          .join(', ');
+      globals.stdio.stderrWrite('Feature flags enabled: $featureFlagsEnabled\n');
       return exitWithHooks(1, shutdownHooks: shutdownHooks);
     }
 

packages/flutter_tools/test/general.shard/runner/runner_test.dart

@@ -34,6 +34,7 @@ void main() {
     int? firstExitCode;
     late MemoryFileSystem fileSystem;
     late FakeAnalytics fakeAnalytics;
+    late FakeStdio fakeStdio;
 
     setUp(() {
       // Instead of exiting with dart:io exit(), this causes an exception to
@@ -58,6 +59,7 @@ void main() {
         fs: fileSystem,
         fakeFlutterVersion: FakeFlutterVersion(),
       );
+      fakeStdio = FakeStdio();
     });
 
     tearDown(() {
@@ -120,6 +122,66 @@ void main() {
       },
     );
 
+    testUsingContext(
+      'error handling crash report (bot)',
+      () async {
+        final Completer<void> completer = Completer<void>();
+        // runner.run() asynchronously calls the exit function set above, so we
+        // catch it in a zone.
+        unawaited(
+          runZonedGuarded<Future<void>?>(
+            () {
+              unawaited(
+                runner.run(
+                  <String>['crash'],
+                  () => <FlutterCommand>[CrashingFlutterCommand()],
+                  // This flutterVersion disables crash reporting.
+                  flutterVersion: '[user-branch]/',
+                  shutdownHooks: ShutdownHooks(),
+                ),
+              );
+              return null;
+            },
+            (Object error, StackTrace stack) {
+              expect(firstExitCode, isNotNull);
+              expect(firstExitCode, isNot(0));
+              expect(error.toString(), 'Exception: test exit');
+              completer.complete();
+            },
+          ),
+        );
+        await completer.future;
+
+        expect(
+          fakeAnalytics.sentEvents,
+          isNot(contains(Event.exception(exception: '_Exception'))),
+          reason: 'Does not send a report on a bot',
+        );
+
+        expect(
+          fakeStdio.writtenToStderr,
+          contains(contains('Feature flags enabled:')),
+          reason: 'Should emit feature flags (ignore specifics for test stability)',
+        );
+      },
+      overrides: <Type, Generator>{
+        Platform:
+            () => FakePlatform(
+              environment: <String, String>{
+                'FLUTTER_ANALYTICS_LOG_FILE': 'test',
+                'FLUTTER_ROOT': '/',
+              },
+            ),
+        FileSystem: () => fileSystem,
+        ProcessManager: () => FakeProcessManager.any(),
+        Artifacts: () => Artifacts.test(),
+        HttpClientFactory: () => () => FakeHttpClient.any(),
+        Analytics: () => fakeAnalytics,
+        BotDetector: () => const FakeBotDetector(true),
+        io.Stdio: () => fakeStdio,
+      },
+    );
+
     // This Completer completes when CrashingFlutterCommand.runCommand
     // completes, but ideally we'd want it to complete when execution resumes
     // runner.run. Currently the distinction does not matter, but if it ever
@@ -282,6 +344,7 @@ void main() {
         fileSystem.currentDirectory = currentDirectory;
         inTestSetup = false;
       });
+
       testUsingContext(
         'create local report in temporary directory',
         () async {