Fix xctest tests

script/tool/lib/src/xctest_command.dart

@@ -6,6 +6,7 @@ import 'dart:convert';
 import 'dart:io' as io;
 
 import 'package:file/file.dart';
+import 'package:platform/platform.dart';
 
 import 'common/core.dart';
 import 'common/package_looping_command.dart';
@@ -31,7 +32,8 @@ class XCTestCommand extends PackageLoopingCommand {
   XCTestCommand(
     Directory packagesDir, {
     ProcessRunner processRunner = const ProcessRunner(),
-  }) : super(packagesDir, processRunner: processRunner) {
+    Platform platform = const LocalPlatform(),
+  }) : super(packagesDir, processRunner: processRunner, platform: platform) {
     argParser.addOption(
       _kiOSDestination,
       help:

script/tool/test/xctest_command_test.dart

@@ -90,16 +90,18 @@ void main() {
 
   group('test xctest_command', () {
     late FileSystem fileSystem;
+    late MockPlatform mockPlatform;
     late Directory packagesDir;
     late CommandRunner<void> runner;
     late RecordingProcessRunner processRunner;
 
     setUp(() {
       fileSystem = MemoryFileSystem();
+      mockPlatform = MockPlatform(isMacOS: true);
       packagesDir = createPackagesDirectory(fileSystem: fileSystem);
       processRunner = RecordingProcessRunner();
-      final XCTestCommand command =
-          XCTestCommand(packagesDir, processRunner: processRunner);
+      final XCTestCommand command = XCTestCommand(packagesDir,
+          processRunner: processRunner, platform: mockPlatform);
 
       runner = CommandRunner<void>('xctest_command', 'Test for xctest_command');
       runner.addCommand(command);