diff --git a/packages/flutter_test/lib/src/_matchers_io.dart b/packages/flutter_test/lib/src/_matchers_io.dart
index 74a3d49760..0c17612d28 100644
--- a/packages/flutter_test/lib/src/_matchers_io.dart
+++ b/packages/flutter_test/lib/src/_matchers_io.dart
@@ -60,8 +60,9 @@ class MatchesGoldenFile extends AsyncMatcher {
     final Uri testNameUri = goldenFileComparator.getTestUri(key, version);
 
     Uint8List? buffer;
-    if (item is Future<List<int>>) {
-      buffer = Uint8List.fromList(await item);
+    if (item is Future<List<int>?>) {
+      final List<int>? bytes = await item;
+      buffer = bytes == null ? null : Uint8List.fromList(bytes);
     } else if (item is List<int>) {
       buffer = Uint8List.fromList(item);
     }
diff --git a/packages/flutter_test/test/matchers_test.dart b/packages/flutter_test/test/matchers_test.dart
index 7e37125c80..36598dc796 100644
--- a/packages/flutter_test/test/matchers_test.dart
+++ b/packages/flutter_test/test/matchers_test.dart
@@ -470,6 +470,14 @@ void main() {
         expect(comparator.imageBytes, equals(<int>[1, 2]));
         expect(comparator.golden, Uri.parse('foo.png'));
       });
+
+      testWidgets('future nullable list of integers',
+          (WidgetTester tester) async {
+        await expectLater(Future<List<int>?>.value(<int>[1, 2]), matchesGoldenFile('foo.png'));
+        expect(comparator.invocation, _ComparatorInvocation.compare);
+        expect(comparator.imageBytes, equals(<int>[1, 2]));
+        expect(comparator.golden, Uri.parse('foo.png'));
+      });
     });
 
     group('does not match', () {