fix #25627 (#25700)

@demotomohiro this was caused by your PR please review
#25627

tests/objects/t25627.nim

@@ -0,0 +1,22 @@
+# issue #25627
+
+import std/tables
+
+type
+  FsoKind = enum
+    fsoFile
+    fsoDir
+    fsoLink
+
+  FakeFso = ref object
+    kind: FsoKind
+    dirName: string
+    files: OrderedTable[string, FakeFso]
+
+  DirStruct = object
+    root = FakeFso(kind: fsoDir, dirName: "/")
+
+let dir = DirStruct()
+doAssert dir.root.kind == fsoDir
+doAssert dir.root.dirName == "/"
+doAssert dir.root.files.len == 0