catch StateError thrown from Chromium.close (flutter#154366)

Fixes crasher flutter#154203.

Also does a little refactoring to move exception handling into the `getChromeTabGuarded` utility function.

I plan on cherry-picking a subset of this change. This would be included in the custom CP patch for flutter#153064.

Author: andrewkolos

packages/flutter_tools/lib/src/isolated/resident_web_runner.dart

@@ -608,20 +608,17 @@ Please provide a valid TCP port (an integer between 0 and 65535, inclusive).
   }) async {
     if (_chromiumLauncher != null) {
       final Chromium chrome = await _chromiumLauncher!.connectedInstance;
-      ChromeTab? chromeTab;
-      try {
-        chromeTab = await getChromeTabGuarded(
-          chrome.chromeConnection,
-          (ChromeTab chromeTab) {
-            return !chromeTab.url.startsWith('chrome-extension');
-          },
-          retryFor: const Duration(seconds: 5),
-        );
-      } on HttpException catch (error, stackTrace) {
-        // We were unable to unable to communicate with Chrome.
-        _logger.printError(error.toString(), stackTrace: stackTrace);
-        chromeTab = null;
-      }
+      final ChromeTab? chromeTab = await getChromeTabGuarded(
+        chrome.chromeConnection,
+        (ChromeTab chromeTab) {
+          return !chromeTab.url.startsWith('chrome-extension');
+        },
+        retryFor: const Duration(seconds: 5),
+        onIoError: (Object error, StackTrace stackTrace) {
+          // We were unable to unable to communicate with Chrome.
+          _logger.printError(error.toString(), stackTrace: stackTrace);
+        }
+      );
       if (chromeTab == null) {
         appFailedToStart();
         throwToolExit('Failed to connect to Chrome instance.');

packages/flutter_tools/lib/src/test/flutter_web_platform.dart

@@ -454,9 +454,6 @@ class FlutterWebPlatform extends PlatformPlugin {
         } on FormatException catch (ex) {
           _logger.printError('Caught FormatException: $ex');
           return shelf.Response.ok('Caught exception: $ex');
-        } on IOException catch (ex) {
-          _logger.printError('Caught IOException: $ex');
-          return shelf.Response.ok('Caught exception: $ex');
         }
       }
       final String? errorMessage = await _testGoldenComparator.compareGoldens(testUri, bytes, goldenKey, updateGoldens);

packages/flutter_tools/lib/src/web/chrome.dart

@@ -6,7 +6,8 @@ import 'dart:async';
 
 import 'package:meta/meta.dart';
 import 'package:process/process.dart';
-import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart';
+import 'package:webkit_inspection_protocol/webkit_inspection_protocol.dart'
+    hide StackTrace;
 
 import '../base/async_guard.dart';
 import '../base/common.dart';
@@ -563,12 +564,37 @@ class Chromium {
   }
 }
 
-// TODO(andrewkolos): Remove when https://github.com/dart-lang/sdk/issues/56566
-//  is fixed.
+
+/// Wrapper for [ChromeConnection.getTab] that will catch any [IOException] or
+/// [StateError], delegate it to the [onIoError] callback, and return null.
+///
+/// This is useful for callers who are want to retrieve a [ChromeTab], but
+/// are okay with the operation failing (e.g. due to an network IO issue or
+/// the Chrome process no longer existing).
 Future<ChromeTab?> getChromeTabGuarded(
   ChromeConnection chromeConnection,
   bool Function(ChromeTab tab) accept, {
   Duration? retryFor,
-}) {
-  return asyncGuard(() => chromeConnection.getTab(accept, retryFor: retryFor));
+  void Function(Object error, StackTrace stackTrace)? onIoError,
+}) async {
+  try {
+    return asyncGuard(
+      () => chromeConnection.getTab(
+        accept,
+        retryFor: retryFor,
+      ),
+    );
+  } on IOException catch (error, stackTrace) {
+    if (onIoError != null) {
+      onIoError(error, stackTrace);
+    }
+    return null;
+    // The underlying HttpClient will throw a StateError when it tries to
+    // perform a request despite the connection already being closed.
+  } on StateError catch (error, stackTrace) {
+    if (onIoError != null) {
+      onIoError(error, stackTrace);
+    }
+    return null;
+  }
 }

packages/flutter_tools/test/web.shard/chrome_test.dart

@@ -758,7 +758,7 @@ void main() {
     expect(logger.errorText, contains('SocketException'));
   });
 
-  test('can recover if getTabs throws a connection exception', () async {
+  testWithoutContext('can recover if getTabs throws a connection exception', () async {
     final BufferLogger logger = BufferLogger.test();
     final FakeChromeConnection chromeConnection = FakeChromeConnection(maxRetries: 4);
     final ChromiumLauncher chromiumLauncher = ChromiumLauncher(
@@ -775,11 +775,11 @@ void main() {
     expect(logger.errorText, isEmpty);
   });
 
-  test('can recover if getTabs throws an HttpException', () async {
+  testWithoutContext('can recover if getTabs throws an HttpException', () async {
     final BufferLogger logger = BufferLogger.test();
     final FakeChromeConnection chromeConnection = FakeChromeConnection(
       maxRetries: 4,
-      exception: io.HttpException(
+      error: io.HttpException(
         'Connection closed before full header was received',
         uri: Uri.parse('http://localhost:52097/json'),
       ),
@@ -798,7 +798,27 @@ void main() {
     expect(logger.errorText, isEmpty);
   });
 
-  test('exits if getTabs throws a connection exception consistently', () async {
+  testWithoutContext('chrome.close can recover if getTab throws a StateError', () async {
+    final BufferLogger logger = BufferLogger.test();
+    final FakeChromeConnection chromeConnection = FakeChromeConnection(
+      maxRetries: 4,
+      error: StateError('Client is closed.'),
+    );
+    final ChromiumLauncher chromiumLauncher = ChromiumLauncher(
+      fileSystem: fileSystem,
+      platform: platform,
+      processManager: processManager,
+      operatingSystemUtils: operatingSystemUtils,
+      browserFinder: findChromeExecutable,
+      logger: logger,
+    );
+    final FakeProcess process = FakeProcess();
+    final Chromium chrome = Chromium(0, chromeConnection, chromiumLauncher: chromiumLauncher, process: process, logger: logger,);
+    await chrome.close();
+    expect(logger.errorText, isEmpty);
+  });
+
+  testWithoutContext('exits if getTabs throws a connection exception consistently', () async {
     final BufferLogger logger = BufferLogger.test();
     final FakeChromeConnection chromeConnection = FakeChromeConnection();
     final ChromiumLauncher chromiumLauncher = ChromiumLauncher(
@@ -825,7 +845,7 @@ void main() {
         ));
   });
 
-  test('Chromium close sends browser close command', () async {
+  testWithoutContext('Chromium close sends browser close command', () async {
     final BufferLogger logger = BufferLogger.test();
     final List<String> commands = <String>[];
     void onSendCommand(String cmd) { commands.add(cmd); }
@@ -845,7 +865,7 @@ void main() {
     expect(commands, contains('Browser.close'));
   });
 
-  test('Chromium close handles a SocketException when connecting to Chrome', () async {
+  testWithoutContext('Chromium close handles a SocketException when connecting to Chrome', () async {
     final BufferLogger logger = BufferLogger.test();
     final FakeChromeConnectionWithTab chromeConnection = FakeChromeConnectionWithTab();
     final ChromiumLauncher chromiumLauncher = ChromiumLauncher(
@@ -863,7 +883,7 @@ void main() {
     await chrome.close();
   });
 
-  test('Chromium close handles a WebSocketException when closing the WipConnection', () async {
+  testWithoutContext('Chromium close handles a WebSocketException when closing the WipConnection', () async {
     final BufferLogger logger = BufferLogger.test();
     final FakeChromeConnectionWithTab chromeConnection = FakeChromeConnectionWithTab(throwWebSocketException: true);
     final ChromiumLauncher chromiumLauncher = ChromiumLauncher(
@@ -887,8 +907,8 @@ class FakeChromeConnection extends Fake implements ChromeConnection {
   /// Create a connection that throws a connection exception on first
   /// [maxRetries] calls to [getTabs].
   /// If [maxRetries] is `null`, [getTabs] calls never succeed.
-  FakeChromeConnection({this.maxRetries, Exception? exception}) : _retries = 0 {
-    this.exception = exception ??
+  FakeChromeConnection({this.maxRetries, Object? error}) : _retries = 0 {
+    this.error = error ??
         ConnectionException(
           formatException: const FormatException('incorrect format'),
           responseStatus: 'OK,',
@@ -899,7 +919,7 @@ class FakeChromeConnection extends Fake implements ChromeConnection {
   final List<ChromeTab> tabs = <ChromeTab>[];
   final int? maxRetries;
   int _retries;
-  late final Exception exception;
+  late final Object error;
 
   @override
   Future<ChromeTab?> getTab(bool Function(ChromeTab tab) accept, {Duration? retryFor}) async {
@@ -910,7 +930,8 @@ class FakeChromeConnection extends Fake implements ChromeConnection {
   Future<List<ChromeTab>> getTabs({Duration? retryFor}) async {
     _retries ++;
     if (maxRetries == null || _retries < maxRetries!) {
-      throw exception;
+      // ignore: only_throw_errors -- This is fine for an ad-hoc test.
+      throw error;
     }
     return tabs;
   }