feat: add list-buckets test for no buckets

We need to check to make sure list-buckets returns a correct
empty list when no buckets created.

tests/integration/group-tests.go

@@ -86,6 +86,7 @@ func TestListBuckets(s *S3Conf) {
 	ListBuckets_invalid_max_buckets(s)
 	ListBuckets_truncated(s)
 	ListBuckets_success(s)
+	ListBuckets_empty_success(s)
 }
 
 func TestDeleteBucket(s *S3Conf) {
@@ -696,6 +697,7 @@ func GetIntTests() IntTests {
 		"ListBuckets_invalid_max_buckets":                                     ListBuckets_invalid_max_buckets,
 		"ListBuckets_truncated":                                               ListBuckets_truncated,
 		"ListBuckets_success":                                                 ListBuckets_success,
+		"ListBuckets_empty_success":                                           ListBuckets_empty_success,
 		"DeleteBucket_non_existing_bucket":                                    DeleteBucket_non_existing_bucket,
 		"DeleteBucket_non_empty_bucket":                                       DeleteBucket_non_empty_bucket,
 		"DeleteBucket_success_status_code":                                    DeleteBucket_success_status_code,

tests/integration/tests.go

@@ -2160,6 +2160,7 @@ func ListBuckets_with_prefix(s *S3Conf) error {
 		return nil
 	})
 }
+
 func ListBuckets_invalid_max_buckets(s *S3Conf) error {
 	testName := "ListBuckets_invalid_max_buckets"
 	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {
@@ -2255,6 +2256,24 @@ func ListBuckets_truncated(s *S3Conf) error {
 	})
 }
 
+func ListBuckets_empty_success(s *S3Conf) error {
+	testName := "ListBuckets_empty_success"
+	return actionHandlerNoSetup(s, testName, func(s3client *s3.Client, bucket string) error {
+		ctx, cancel := context.WithTimeout(context.Background(), shortTimeout)
+		out, err := s3client.ListBuckets(ctx, &s3.ListBucketsInput{})
+		cancel()
+		if err != nil {
+			return err
+		}
+
+		if len(out.Buckets) > 0 {
+			return fmt.Errorf("expected list buckets result to be %v, instead got %v", []types.Bucket{}, out.Buckets)
+		}
+
+		return nil
+	})
+}
+
 func ListBuckets_success(s *S3Conf) error {
 	testName := "ListBuckets_success"
 	return actionHandler(s, testName, func(s3client *s3.Client, bucket string) error {

tests/integration/utils.go

@@ -213,6 +213,21 @@ func actionHandler(s *S3Conf, testName string, handler func(s3client *s3.Client,
 	return handlerErr
 }
 
+func actionHandlerNoSetup(s *S3Conf, testName string, handler func(s3client *s3.Client, bucket string) error, _ ...setupOpt) error {
+	runF(testName)
+	client := s3.NewFromConfig(s.Config())
+	handlerErr := handler(client, "")
+	if handlerErr != nil {
+		failF("%v: %v", testName, handlerErr)
+	}
+
+	if handlerErr == nil {
+		passF(testName)
+	}
+
+	return handlerErr
+}
+
 type authConfig struct {
 	testName string
 	path     string