feat(shorebird_cli): add shorebird flutter config command (#2984)

packages/shorebird_cli/lib/src/commands/flutter/config/config.dart

@@ -0,0 +1 @@
+export 'flutter_config_command.dart';

packages/shorebird_cli/lib/src/commands/flutter/config/flutter_config_command.dart

@@ -0,0 +1,20 @@
+import 'dart:async';
+
+import 'package:shorebird_cli/src/shorebird_command.dart';
+import 'package:shorebird_cli/src/shorebird_process.dart';
+
+/// {@template flutter_config_command}
+/// `shorebird flutter config`
+/// Manage your Shorebird Flutter Config.
+/// {@endtemplate}
+class FlutterConfigCommand extends ShorebirdProxyCommand {
+  @override
+  String get description =>
+      'Configure Flutter settings. This proxies to the underlying `flutter config` command.';
+
+  @override
+  String get name => 'config';
+
+  @override
+  FutureOr<int> run() => process.stream('flutter', ['config', ...results.rest]);
+}

packages/shorebird_cli/lib/src/commands/flutter/flutter.dart

@@ -1,2 +1,3 @@
+export 'config/config.dart';
 export 'flutter_command.dart';
 export 'versions/versions.dart';

packages/shorebird_cli/lib/src/commands/flutter/flutter_command.dart

@@ -9,6 +9,7 @@ class FlutterCommand extends ShorebirdCommand {
   /// {@macro flutter_command}
   FlutterCommand() {
     addSubcommand(FlutterVersionsCommand());
+    addSubcommand(FlutterConfigCommand());
   }
 
   @override

packages/shorebird_cli/lib/src/shorebird_command.dart

@@ -44,3 +44,11 @@ abstract class ShorebirdCommand extends Command<int> {
   /// [ArgResults] for the current command.
   ArgResults get results => testArgResults ?? argResults!;
 }
+
+/// {@template shorebird_proxy_command}
+/// A command in the Shorebird CLI that proxies to an underlying process.
+/// {@endtemplate}
+abstract class ShorebirdProxyCommand extends ShorebirdCommand {
+  @override
+  ArgParser get argParser => ArgParser.allowAnything();
+}

packages/shorebird_cli/test/src/commands/flutter/config/flutter_config_command_test.dart

@@ -0,0 +1,54 @@
+import 'package:args/args.dart';
+import 'package:mason_logger/mason_logger.dart';
+import 'package:mocktail/mocktail.dart';
+import 'package:scoped_deps/scoped_deps.dart';
+import 'package:shorebird_cli/src/commands/flutter/config/flutter_config_command.dart';
+import 'package:shorebird_cli/src/shorebird_process.dart';
+import 'package:test/test.dart';
+
+import '../../../mocks.dart';
+
+void main() {
+  group(FlutterConfigCommand, () {
+    late ShorebirdProcess process;
+    late ArgResults argResults;
+    late FlutterConfigCommand command;
+
+    R runWithOverrides<R>(R Function() body) {
+      return runScoped(body, values: {processRef.overrideWith(() => process)});
+    }
+
+    setUp(() {
+      argResults = MockArgResults();
+      process = MockShorebirdProcess();
+      command = runWithOverrides(FlutterConfigCommand.new)
+        ..testArgResults = argResults;
+    });
+
+    test('has correct name and description', () {
+      expect(command.name, equals('config'));
+      expect(
+        command.description,
+        equals(
+          'Configure Flutter settings. This proxies to the underlying `flutter config` command.',
+        ),
+      );
+    });
+
+    test('runs the `flutter config` command', () async {
+      final exitCode = ExitCode.success.code;
+      final args = ['--jdk-dir', '/path/to/jdk'];
+      when(() => argResults.rest).thenReturn(args);
+      when(
+        () => process.stream('flutter', ['config', ...args]),
+      ).thenAnswer((_) async => exitCode);
+
+      await expectLater(
+        runWithOverrides(command.run),
+        completion(equals(exitCode)),
+      );
+
+      verify(() => process.stream('flutter', ['config', ...args])).called(1);
+    });
+  });
+}