s3: count stored versions as bucket contents on delete (#11775)

* s3: count stored versions as bucket contents

A <key>.versions directory holding version entries is user data; skipping
it let bucketHasUserObjects report an empty bucket while the recursive
delete dropped every stored version.

* test: rename stale reserved-folders case in bucket delete test

.versions directories are now descended into, so the case only holds
because the folder is empty.

weed/s3api/s3api_bucket_delete_test.go

@@ -152,7 +152,7 @@ func TestBucketHasUserObjects_EmptyDirectories(t *testing.T) {
 			wantHasUser: true,
 		},
 		{
-			name: "bucket with only reserved folders (.uploads, *.versions)",
+			name: "empty *.versions folder and .uploads do not count",
 			entriesByDir: map[string][]*filer_pb.Entry{
 				"/buckets/b": {
 					{Name: s3_constants.MultipartUploadsFolder, IsDirectory: true},
@@ -162,7 +162,7 @@ func TestBucketHasUserObjects_EmptyDirectories(t *testing.T) {
 			wantHasUser: false,
 		},
 		{
-			name: "nested versions-named directories are internal",
+			name: "nested versions directory with stored versions counts",
 			entriesByDir: map[string][]*filer_pb.Entry{
 				"/buckets/b": {
 					{Name: "logs", IsDirectory: true},
@@ -174,6 +174,19 @@ func TestBucketHasUserObjects_EmptyDirectories(t *testing.T) {
 					{Name: "v1", IsDirectory: false},
 				},
 			},
+			wantHasUser: true,
+		},
+		{
+			name: "nested versions directory left empty does not count",
+			entriesByDir: map[string][]*filer_pb.Entry{
+				"/buckets/b": {
+					{Name: "logs", IsDirectory: true},
+				},
+				"/buckets/b/logs": {
+					{Name: "foo" + s3_constants.VersionsFolder, IsDirectory: true},
+				},
+				"/buckets/b/logs/foo" + s3_constants.VersionsFolder: {},
+			},
 			wantHasUser: false,
 		},
 		{