hugofs: Fix mount with hole regression

Fixes #6854

hugofs/decorators.go

@@ -81,12 +81,28 @@ func DecorateBasePathFs(base *afero.BasePathFs) afero.Fs {
 // NewBaseFileDecorator decorates the given Fs to provide the real filename
 // and an Opener func.
 func NewBaseFileDecorator(fs afero.Fs) afero.Fs {
-
 	ffs := &baseFileDecoratorFs{Fs: fs}
 
 	decorator := func(fi os.FileInfo, filename string) (os.FileInfo, error) {
 		// Store away the original in case it's a symlink.
 		meta := FileMeta{metaKeyName: fi.Name()}
+		if fi.IsDir() {
+			meta[metaKeyJoinStat] = func(name string) (FileMetaInfo, error) {
+				joinedFilename := filepath.Join(filename, name)
+				fi, _, err := lstatIfPossible(fs, joinedFilename)
+				if err != nil {
+					return nil, err
+				}
+
+				fi, err = ffs.decorate(fi, joinedFilename)
+				if err != nil {
+					return nil, err
+				}
+
+				return fi.(FileMetaInfo), nil
+			}
+		}
+
 		isSymlink := isSymlink(fi)
 		if isSymlink {
 			meta[metaKeyOriginalFilename] = filename