diff --git a/predicatefs.go b/predicatefs.go
index 12f28e7..29332c9 100644
--- a/predicatefs.go
+++ b/predicatefs.go
@@ -8,10 +8,12 @@ import (
 	"time"
 )
 
+type predFn func(bool, string) bool
+
 // FilePredicateFs filters files (not directories) by predicate,
 // which takes file path as an arg.
 type FilePredicateFs struct {
-	pred   func(string) bool
+	pred   predFn
 	source Fs
 }
 
@@ -19,49 +21,43 @@ var (
 	_ fs.ReadDirFile = (*PredicateFile)(nil)
 )
 
-func NewFilePredicateFs(source Fs, pred func(string) bool) Fs {
+func NewFilePredicateFs(source Fs, pred predFn) Fs {
 	return &FilePredicateFs{source: source, pred: pred}
 }
 
 type PredicateFile struct {
 	f    File
-	pred func(string) bool
+	pred predFn
 }
 
 func (p *FilePredicateFs) validate(path string) error {
-	if p.pred(path) {
+	dir, err := IsDir(p.source, path)
+	if err != nil {
+		return err
+	}
+
+	if p.pred(dir, path) {
 		return nil
 	}
 	return syscall.ENOENT
 }
 
-func (p *FilePredicateFs) dirOrValidPath(path string) error {
-	dir, err := IsDir(p.source, path)
-	if err != nil {
-		return err
-	}
-	if dir {
-		return nil
-	}
-	return p.validate(path)
-}
-
 func (p *FilePredicateFs) Chtimes(path string, a, m time.Time) error {
-	if err := p.dirOrValidPath(path); err != nil {
+	if err := p.validate(path); err != nil {
 		return err
 	}
 	return p.source.Chtimes(path, a, m)
 }
 
 func (p *FilePredicateFs) Chmod(path string, mode os.FileMode) error {
-	if err := p.dirOrValidPath(path); err != nil {
+	if err := p.validate(path); err != nil {
 		return err
 	}
 	return p.source.Chmod(path, mode)
 }
 
 func (p *FilePredicateFs) Chown(path string, uid, gid int) error {
-	if err := p.dirOrValidPath(path); err != nil {
+	if err := p.validate(path); err != nil {
 		return err
 	}
 	return p.source.Chown(path, uid, gid)
@@ -72,7 +68,7 @@ func (p *FilePredicateFs) Name() string {
 }
 
 func (p *FilePredicateFs) Stat(path string) (os.FileInfo, error) {
-	if err := p.dirOrValidPath(path); err != nil {
+	if err := p.validate(path); err != nil {
 		return nil, err
 	}
 	return p.source.Stat(path)
@@ -96,42 +92,30 @@ func (p *FilePredicateFs) Rename(oldname, newname string) error {
 }
 
 func (p *FilePredicateFs) RemoveAll(path string) error {
-	dir, err := IsDir(p.source, path)
-	if err != nil {
+	if err := p.validate(path); err != nil {
 		return err
 	}
-	if !dir {
-		if err := p.validate(path); err != nil {
-			return err
-		}
-	}
 	return p.source.RemoveAll(path)
 }
 
 func (p *FilePredicateFs) Remove(path string) error {
-	if err := p.dirOrValidPath(path); err != nil {
+	if err := p.validate(path); err != nil {
 		return err
 	}
 	return p.source.Remove(path)
 }
 
 func (p *FilePredicateFs) OpenFile(path string, flag int, perm os.FileMode) (File, error) {
-	if err := p.dirOrValidPath(path); err != nil {
+	if err := p.validate(path); err != nil {
 		return nil, err
 	}
 	return p.source.OpenFile(path, flag, perm)
 }
 
 func (p *FilePredicateFs) Open(path string) (File, error) {
-	dir, err := IsDir(p.source, path)
-	if err != nil {
+	if err := p.validate(path); err != nil {
 		return nil, err
 	}
-	if !dir {
-		if err := p.validate(path); err != nil {
-			return nil, err
-		}
-	}
 	f, err := p.source.Open(path)
 	if err != nil {
 		return nil, err
@@ -182,18 +166,18 @@ func (f *PredicateFile) Name() string {
 	return f.f.Name()
 }
 
-func (f *PredicateFile) Readdir(c int) (fi []os.FileInfo, err error) {
-	var pfi []os.FileInfo
-	pfi, err = f.f.Readdir(c)
+func (f *PredicateFile) Readdir(c int) (filtered []os.FileInfo, err error) {
+	var infos []os.FileInfo
+	infos, err = f.f.Readdir(c)
 	if err != nil {
 		return nil, err
 	}
-	for _, i := range pfi {
-		if i.IsDir() || f.pred(filepath.Join(f.f.Name(), i.Name())) {
-			fi = append(fi, i)
+	for _, i := range infos {
+		if f.pred(i.IsDir(), filepath.Join(f.f.Name(), i.Name())) {
+			filtered = append(filtered, i)
 		}
 	}
-	return fi, nil
+	return filtered, nil
 }
 
 func (f *PredicateFile) ReadDir(n int) (filtered []fs.DirEntry, err error) {
@@ -207,12 +191,11 @@ func (f *PredicateFile) ReadDir(n int) (filtered []fs.DirEntry, err error) {
 		return nil, err
 	}
 	for _, e := range entreis {
-		if e.IsDir() || f.pred(filepath.Join(f.f.Name(), e.Name())) {
+		if f.pred(e.IsDir(), filepath.Join(f.f.Name(), e.Name())) {
 			filtered = append(filtered, e)
 		}
 	}
 	return filtered, nil
-
 }
 
 func (f *PredicateFile) Readdirnames(c int) (n []string, err error) {
diff --git a/predicatefs_test.go b/predicatefs_test.go
index 74040cd..03cad18 100644
--- a/predicatefs_test.go
+++ b/predicatefs_test.go
@@ -26,8 +26,8 @@ func TestFilePredicateFs(t *testing.T) {
 		return strings.HasSuffix(filepath.Dir(path), ".hidden")
 	}
 
-	pred := func(path string) bool {
-		return nonEmpty(path) && txtExts(path) && !inHiddenDir(path)
+	pred := func(isDir bool, path string) bool {
+		return isDir || (nonEmpty(path) && txtExts(path) && !inHiddenDir(path))
 	}
 
 	fs := &FilePredicateFs{pred: pred, source: mfs}