Don't crash flutter tool if Chrome is not available (#154941)

Instead of unawaiting the future, let's ignore it. 

Fixes issue #154940


I am not sure if tests would be required for this change or not.

## Pre-launch Checklist

- [ ] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [ ] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [ ] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [ ] I signed the [CLA].
- [ ] I listed at least one issue that this PR fixes in the description
above.
- [ ] I updated/added relevant documentation (doc comments with `///`).
- [ ] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [ ] All existing and new tests are passing.

If you need help, consider asking for advice on the #hackers-new channel
on [Discord].

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[Features we expect every widget to implement]:
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[CLA]: https://cla.developers.google.com/
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[breaking change policy]:
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[Discord]:
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[Data Driven Fixes]:
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---------

Co-authored-by: Christopher Fujino <christopherfujino@gmail.com>
Co-authored-by: Andrew Kolos <andrewrkolos@gmail.com>
Co-authored-by: Ben Konyi <bkonyi@google.com>

packages/flutter_tools/lib/src/resident_devtools_handler.dart

@@ -8,23 +8,25 @@
 
 import 'dart:async';
 
-import 'package:browser_launcher/browser_launcher.dart';
 import 'package:meta/meta.dart';
 
+import 'base/io.dart';
 import 'base/logger.dart';
 import 'build_info.dart';
 import 'resident_runner.dart';
 import 'vmservice.dart';
+import 'web/chrome.dart';
 
 typedef ResidentDevtoolsHandlerFactory =
-    ResidentDevtoolsHandler Function(DevtoolsLauncher?, ResidentRunner, Logger);
+    ResidentDevtoolsHandler Function(DevtoolsLauncher?, ResidentRunner, Logger, ChromiumLauncher);
 
 ResidentDevtoolsHandler createDefaultHandler(
   DevtoolsLauncher? launcher,
   ResidentRunner runner,
   Logger logger,
+  ChromiumLauncher chromiumLauncher,
 ) {
-  return FlutterResidentDevtoolsHandler(launcher, runner, logger);
+  return FlutterResidentDevtoolsHandler(launcher, runner, logger, chromiumLauncher);
 }
 
 /// Helper class to manage the life-cycle of devtools and its interaction with
@@ -66,12 +68,18 @@ abstract class ResidentDevtoolsHandler {
 }
 
 class FlutterResidentDevtoolsHandler implements ResidentDevtoolsHandler {
-  FlutterResidentDevtoolsHandler(this._devToolsLauncher, this._residentRunner, this._logger);
+  FlutterResidentDevtoolsHandler(
+    this._devToolsLauncher,
+    this._residentRunner,
+    this._logger,
+    this._chromiumLauncher,
+  );
 
   static const Duration launchInBrowserTimeout = Duration(seconds: 15);
 
   final DevtoolsLauncher? _devToolsLauncher;
   final ResidentRunner _residentRunner;
+  final ChromiumLauncher _chromiumLauncher;
   final Logger _logger;
   bool _shutdown = false;
 
@@ -184,11 +192,14 @@ class FlutterResidentDevtoolsHandler implements ResidentDevtoolsHandler {
                 queryParameters: <String, dynamic>{'uri': '${device!.vmService!.httpAddress}'},
               )
               .toString();
-      _logger.printStatus(
+      _logger.printStatus('Launching Flutter DevTools for ${device.device!.name} at $devToolsUrl');
-        'Launching Flutter DevTools for '
+
-        '${device.device!.displayName} at $devToolsUrl',
+      _chromiumLauncher.launch(devToolsUrl).catchError((Object e) {
-      );
+        _logger.printError('Failed to launch web browser: $e');
-      unawaited(Chrome.start(<String>[devToolsUrl]));
+        throw ProcessException('Chrome', <String>[
+          devToolsUrl,
+        ], 'Failed to launch browser for dev tools');
+      }).ignore();
     }
     launchedInBrowser = true;
   }
@@ -316,6 +327,7 @@ NoOpDevtoolsHandler createNoOpHandler(
   DevtoolsLauncher? launcher,
   ResidentRunner runner,
   Logger logger,
+  ChromiumLauncher? chromiumLauncher,
 ) {
   return NoOpDevtoolsHandler();
 }

packages/flutter_tools/lib/src/resident_runner.dart

@@ -41,6 +41,7 @@ import 'run_cold.dart';
 import 'run_hot.dart';
 import 'sksl_writer.dart';
 import 'vmservice.dart';
+import 'web/chrome.dart';
 
 class FlutterDevice {
   FlutterDevice(
@@ -1048,7 +1049,19 @@ abstract class ResidentRunner extends ResidentHandlers {
       artifactDirectory.createSync(recursive: true);
     }
     // TODO(bkonyi): remove when ready to serve DevTools from DDS.
-    _residentDevtoolsHandler = devtoolsHandler(DevtoolsLauncher.instance, this, globals.logger);
+    _residentDevtoolsHandler = devtoolsHandler(
+      DevtoolsLauncher.instance,
+      this,
+      globals.logger,
+      ChromiumLauncher(
+        fileSystem: globals.fs,
+        platform: globals.platform,
+        processManager: globals.processManager,
+        operatingSystemUtils: globals.os,
+        browserFinder: findChromeExecutable,
+        logger: globals.logger,
+      ),
+    );
   }
 
   @override

packages/flutter_tools/pubspec.yaml

@@ -12,7 +12,6 @@ dependencies:
   # https://github.com/flutter/flutter/blob/main/docs/infra/Updating-dependencies-in-Flutter.md
   archive: 3.6.1
   args: 2.6.0
-  browser_launcher: 1.1.3
   dds: 5.0.0
   dwds: 24.3.2
   completion: 1.0.1
@@ -71,6 +70,7 @@ dependencies:
   _fe_analyzer_shared: 76.0.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   analyzer: 6.11.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   boolean_selector: 2.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
+  browser_launcher: 1.1.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   built_collection: 5.1.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   built_value: 8.9.3 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   clock: 1.1.2 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"

packages/flutter_tools/test/general.shard/resident_devtools_handler_test.dart

@@ -6,6 +6,8 @@ import 'dart:async';
 
 import 'package:flutter_tools/src/artifacts.dart';
 import 'package:flutter_tools/src/base/dds.dart';
+import 'package:flutter_tools/src/base/file_system.dart';
+import 'package:flutter_tools/src/base/io.dart';
 import 'package:flutter_tools/src/base/logger.dart';
 import 'package:flutter_tools/src/build_info.dart';
 import 'package:flutter_tools/src/cache.dart';
@@ -14,6 +16,7 @@ import 'package:flutter_tools/src/devtools_launcher.dart';
 import 'package:flutter_tools/src/resident_devtools_handler.dart';
 import 'package:flutter_tools/src/resident_runner.dart';
 import 'package:flutter_tools/src/vmservice.dart';
+import 'package:flutter_tools/src/web/chrome.dart';
 import 'package:test/fake.dart';
 import 'package:vm_service/vm_service.dart' as vm_service;
 import 'package:vm_service/vm_service.dart';
@@ -58,6 +61,7 @@ void main() {
       null,
       FakeResidentRunner(),
       BufferLogger.test(),
+      _FakeChromiumLauncher(),
     );
 
     await handler.serveAndAnnounceDevTools(flutterDevices: <FlutterDevice>[]);
@@ -72,8 +76,8 @@ void main() {
         FakeDevtoolsLauncher(),
         FakeResidentRunner()..supportsServiceProtocol = false,
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
-
       await handler.serveAndAnnounceDevTools(flutterDevices: <FlutterDevice>[]);
 
       expect(handler.activeDevToolsServer, null);
@@ -94,6 +98,7 @@ void main() {
       launcher,
       FakeResidentRunner(),
       BufferLogger.test(),
+      _FakeChromiumLauncher(),
     );
 
     await handler.serveAndAnnounceDevTools(
@@ -114,6 +119,7 @@ void main() {
           ..devToolsUrl = Uri.parse('http://localhost:8080'),
         FakeResidentRunner(),
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
 
       // VM Service is intentionally null
@@ -132,6 +138,7 @@ void main() {
           ..devToolsUrl = Uri.parse('http://localhost:8080'),
         FakeResidentRunner(),
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
       final FakeVmServiceHost fakeVmServiceHost = FakeVmServiceHost(
         requests: <VmServiceExpectation>[
@@ -170,6 +177,7 @@ void main() {
       FakeDevtoolsLauncher()..activeDevToolsServer = null,
       FakeResidentRunner(),
       BufferLogger.test(),
+      _FakeChromiumLauncher(),
     );
     final FakeVmServiceHost fakeVmServiceHost = FakeVmServiceHost(
       requests: <VmServiceExpectation>[],
@@ -188,6 +196,7 @@ void main() {
         ..devToolsUrl = Uri.parse('http://localhost:8080'),
       FakeResidentRunner(),
       BufferLogger.test(),
+      _FakeChromiumLauncher(),
     );
     final FakeVmServiceHost fakeVmServiceHost = FakeVmServiceHost(
       requests: <VmServiceExpectation>[
@@ -228,6 +237,7 @@ void main() {
         FakeDevtoolsLauncher()..activeDevToolsServer = DevToolsServerAddress('localhost', 8080),
         FakeResidentRunner(),
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
       final FakeVmServiceHost fakeVmServiceHost = FakeVmServiceHost(
         requests: <VmServiceExpectation>[
@@ -258,6 +268,7 @@ void main() {
           ..devToolsUrl = Uri.parse('http://localhost:8080'),
         FakeResidentRunner(),
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
 
       final FakeVmServiceHost vmServiceHost = FakeVmServiceHost(
@@ -314,6 +325,7 @@ void main() {
       null,
       FakeResidentRunner(),
       BufferLogger.test(),
+      _FakeChromiumLauncher(),
     );
 
     handler.launchDevToolsInBrowser(flutterDevices: <FlutterDevice>[]);
@@ -328,6 +340,7 @@ void main() {
         FakeDevtoolsLauncher(),
         FakeResidentRunner()..supportsServiceProtocol = false,
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
 
       handler.launchDevToolsInBrowser(flutterDevices: <FlutterDevice>[]);
@@ -349,6 +362,7 @@ void main() {
           ..readyCompleter = completer,
         FakeResidentRunner(),
         BufferLogger.test(),
+        _FakeChromiumLauncher(),
       );
 
       expect(handler.launchDevToolsInBrowser(flutterDevices: <FlutterDevice>[]), isTrue);
@@ -369,12 +383,27 @@ void main() {
         ..activeDevToolsServer = DevToolsServerAddress('localhost', 8080),
       FakeResidentRunner(),
       BufferLogger.test(),
+      _FakeChromiumLauncher(),
     );
 
     expect(handler.launchDevToolsInBrowser(flutterDevices: <FlutterDevice>[]), isTrue);
     expect(handler.launchedInBrowser, isTrue);
   });
 
+  testWithoutContext('launchDevToolsInBrowser fails without Chrome installed', () async {
+    final FlutterResidentDevtoolsHandler handler = FlutterResidentDevtoolsHandler(
+      FakeDevtoolsLauncher()
+        ..devToolsUrl = Uri(host: 'localhost', port: 8080)
+        ..activeDevToolsServer = DevToolsServerAddress('localhost', 8080),
+      FakeResidentRunner(),
+      BufferLogger.test(),
+      _ThrowingChromiumLauncher(),
+    );
+
+    expect(handler.launchedInBrowser, isFalse);
+    expect(handler.launchDevToolsInBrowser(flutterDevices: <FlutterDevice>[]), isTrue);
+  });
+
   testWithoutContext(
     'Converts a VM Service URI with a query parameter to a pretty display string',
     () {
@@ -443,3 +472,19 @@ class FakeDartDevelopmentService extends Fake implements DartDevelopmentService
     disposed = true;
   }
 }
+
+class _ThrowingChromiumLauncher extends Fake implements ChromiumLauncher {
+  @override
+  Future<Chromium> launch(
+    String url, {
+    bool headless = false,
+    int? debugPort,
+    bool skipCheck = false,
+    Directory? cacheDir,
+    List<String> webBrowserFlags = const <String>[],
+  }) async {
+    throw ProcessException('ChromiumLauncher', <String>[url]);
+  }
+}
+
+class _FakeChromiumLauncher extends Fake implements ChromiumLauncher {}