fix: replace Future.delayed with explicit timestamps in tests (#3497)

packages/shorebird_cli/test/src/artifact_manager_test.dart

@@ -597,7 +597,7 @@ void main() {
         late Directory oldArchiveDirectory;
         late Directory newArchiveDirectory;
 
-        setUp(() async {
+        setUp(() {
           oldArchiveDirectory = Directory(
             p.join(
               projectRoot.path,
@@ -607,9 +607,6 @@ void main() {
               'Runner.xcarchive',
             ),
           )..createSync(recursive: true);
-          // Wait to ensure the new archive directory is created after the old
-          // archive directory.
-          await Future<void>.delayed(const Duration(milliseconds: 50));
           newArchiveDirectory = Directory(
             p.join(
               projectRoot.path,
@@ -619,6 +616,9 @@ void main() {
               'Runner2.xcarchive',
             ),
           )..createSync(recursive: true);
+          // Set explicit modification times so newArchiveDirectory is newer.
+          _setDirectoryMtime(oldArchiveDirectory, DateTime(2024));
+          _setDirectoryMtime(newArchiveDirectory, DateTime(2025));
         });
 
         test('selects the most recently updated xcarchive', () async {
@@ -688,7 +688,7 @@ void main() {
         late Directory oldAppDirectory;
         late Directory newAppDirectory;
 
-        setUp(() async {
+        setUp(() {
           oldAppDirectory = Directory(
             p.join(
               projectRoot.path,
@@ -700,9 +700,6 @@ void main() {
               'Runner.app',
             ),
           )..createSync(recursive: true);
-          // Wait to ensure the new app directory is created after the old
-          // app directory.
-          await Future<void>.delayed(const Duration(milliseconds: 50));
           newAppDirectory = Directory(
             p.join(
               projectRoot.path,
@@ -714,6 +711,9 @@ void main() {
               'Runner2.app',
             ),
           )..createSync(recursive: true);
+          // Set explicit modification times so newAppDirectory is newer.
+          _setDirectoryMtime(oldAppDirectory, DateTime(2024));
+          _setDirectoryMtime(newAppDirectory, DateTime(2025));
         });
 
         test('selects the most recently updated app', () async {
@@ -1000,3 +1000,41 @@ void main() {
     });
   });
 }
+
+/// Sets the modification time of [directory] to [mtime].
+///
+/// Dart's [Directory] does not expose `setLastModifiedSync`, so we shell out
+/// to platform-specific commands.
+void _setDirectoryMtime(Directory directory, DateTime mtime) {
+  final ProcessResult result;
+  if (Platform.isWindows) {
+    final formatted = mtime.toIso8601String();
+    result = Process.runSync('powershell', [
+      '-Command',
+      "(Get-Item '${directory.path}').LastWriteTime = '$formatted'",
+    ]);
+  } else {
+    result = Process.runSync('touch', [
+      '-t',
+      _toTouchTimestamp(mtime),
+      directory.path,
+    ]);
+  }
+  if (result.exitCode != 0) {
+    throw ProcessException(
+      'Failed to set mtime',
+      [],
+      '${result.stderr}',
+      result.exitCode,
+    );
+  }
+}
+
+String _toTouchTimestamp(DateTime dt) {
+  final y = dt.year.toString().padLeft(4, '0');
+  final m = dt.month.toString().padLeft(2, '0');
+  final d = dt.day.toString().padLeft(2, '0');
+  final h = dt.hour.toString().padLeft(2, '0');
+  final min = dt.minute.toString().padLeft(2, '0');
+  return '$y$m$d$h$min';
+}

packages/shorebird_cli/test/src/platform/windows/windows_test.dart

@@ -62,11 +62,12 @@ void main() {
       group('when an exact match does not exist', () {
         late File app;
 
-        setUp(() async {
-          File(p.join(tempDir.path, 'other.exe')).createSync();
-          // Ensure my_app is created after other.
-          await Future<void>.delayed(const Duration(seconds: 1));
+        setUp(() {
+          final other = File(p.join(tempDir.path, 'other.exe'))..createSync();
           app = File(p.join(tempDir.path, '$projectName.exe'))..createSync();
+          // Set modification times so my_app is newer than other.
+          other.setLastModifiedSync(DateTime(2024));
+          app.setLastModifiedSync(DateTime(2025));
         });
 
         test('returns most recently modified executable', () {