diff --git a/file_test.go b/file_test.go
index 8abf469..4c67a5b 100644
--- a/file_test.go
+++ b/file_test.go
@@ -3,13 +3,13 @@ package main
 import (
   "io"
   "os"
-  "errors"
   "reflect"
-  "strings"
   "strconv"
   "testing"
   "io/ioutil"
   "path/filepath"
+
+  "github.com/JamTools/goff/fsutil"
 )
 
 func tmpFile(t *testing.T, input string, f func(in *os.File)) {
@@ -30,45 +30,6 @@ func tmpFile(t *testing.T, input string, f func(in *os.File)) {
   f(in)
 }
 
-type testFile struct {
-  name, contents string
-}
-
-func createTestFiles(files []*testFile, t *testing.T) string {
-  td, err := ioutil.TempDir("", "")
-  if err != nil {
-    t.Fatal(err)
-  }
-
-  for i := range files {
-    if len(files[i].name) == 0 {
-      continue
-    }
-
-    pa := strings.Split(files[i].name, "/")
-    p := filepath.Join(td, filepath.Join(pa[:len(pa)-1]...))
-
-    // create parent dirs
-    if len(pa) > 1 {
-      err := os.MkdirAll(p, 0777)
-      if err != nil {
-        t.Fatal(err)
-      }
-    }
-
-    // create file
-    if len(pa[len(pa)-1]) > 0 {
-      fullpath := filepath.Join(p, pa[len(pa)-1])
-      err := ioutil.WriteFile(fullpath, []byte(files[i].contents), 0644)
-      if err != nil {
-        t.Fatal(err)
-      }
-    }
-  }
-
-  return td
-}
-
 func TestPathInfo(t *testing.T) {
   tests := []struct {
     artist, base, path string
@@ -140,58 +101,6 @@ func TestOnlyDir(t *testing.T) {
   }
 }
 
-func TestFilesByExtensionImages(t *testing.T) {
-  files := []*testFile{
-    {"file1", ""},
-    {"file2.jpeg", ""},
-    {"dir1/file3.JPG", ""},
-    {"dir1/dir2/file4.png", ""},
-  }
-
-  result := []string{
-    "dir1/dir2/file4.png",
-    "dir1/file3.JPG",
-    "file2.jpeg",
-  }
-
-  dir := createTestFiles(files, t)
-  defer os.RemoveAll(dir)
-
-  paths := filesByExtension(dir, imageExts)
-  if strings.Join(paths, "\n") != strings.Join(result, "\n") {
-    t.Errorf("Expected %v, got %v", result, paths)
-  }
-}
-
-func TestFilesByExtensionAudio(t *testing.T) {
-  files := []*testFile{
-    {"not audio file", ""},
-    {"file1.FLAC", ""},
-    {"file2.m4a", ""},
-    {"dir1/file3.mp3", ""},
-    {"dir1/dir2/file4.mp4", ""},
-    {"dir1/dir2/file5.SHN", ""},
-    {"dir1/dir2/file6.WAV", ""},
-  }
-
-  result := []string{
-    "dir1/dir2/file4.mp4",
-    "dir1/dir2/file5.SHN",
-    "dir1/dir2/file6.WAV",
-    "dir1/file3.mp3",
-    "file1.FLAC",
-    "file2.m4a",
-  }
-
-  dir := createTestFiles(files, t)
-  defer os.RemoveAll(dir)
-
-  paths := filesByExtension(dir, audioExts)
-  if strings.Join(paths, "\n") != strings.Join(result, "\n") {
-    t.Errorf("Expected %v, got %v", result, paths)
-  }
-}
-
 func TestBundleFiles(t *testing.T) {
   testFiles := []string{
     "artist1/file1",
@@ -250,111 +159,8 @@ func TestSafeFilename(t *testing.T) {
   }
 }
 
-func testFilesFullPath(t *testing.T, f func(dir string, files []string)) {
-  newFiles := []*testFile{
-    {"file1", "abcde"},
-    {"file2.jpeg", "a"},
-    {"dir1/file3.JPG", "acddfefsefd"},
-    {"dir1/dir2/file4.png", "dfadfd"},
-  }
-
-  dir := createTestFiles(newFiles, t)
-  defer os.RemoveAll(dir)
-
-  files := []string{}
-  for i := range newFiles {
-    files = append(files, filepath.Join(dir, newFiles[i].name))
-  }
-
-  f(dir, files)
-}
-
-func TestNthFileSize(t *testing.T) {
-  tests := []struct {
-    smallest bool
-    result string
-    other string
-  }{
-    { smallest: true, result: "file2.jpeg" },
-    { smallest: false, result: "dir1/file3.JPG" },
-    { other: "audiocc-file-def-dne", result: "" },
-  }
-
-  testFilesFullPath(t, func(dir string, files []string) {
-    for i := range tests {
-      // test file does not exist
-      if len(tests[i].other) > 0 {
-        files = []string{ tests[i].other }
-      }
-      r, err := nthFileSize(files, tests[i].smallest)
-
-      // test errors by setting empty result
-      if err != nil && tests[i].result == "" {
-        continue
-      }
-
-      res := filepath.Join(dir, tests[i].result)
-      if r != res {
-        t.Errorf("Expected %v, got %v", res, r)
-      }
-    }
-  })
-}
-
-func TestIsLarger(t *testing.T) {
-  testFilesFullPath(t, func(dir string, files []string) {
-    tests := []struct {
-      src, dest string
-      result bool
-    }{
-      { src: files[0], dest: files[1], result: true },
-      { src: files[1], dest: files[0], result: false },
-      { src: files[2], dest: files[3], result: true },
-      { src: "audiocc-file-def-dne", dest: files[3], result: false },
-    }
-
-    for i := range tests {
-      r := isLarger(tests[i].src, tests[i].dest)
-      if r != tests[i].result {
-        t.Errorf("Expected %v, got %v", tests[i].result, r)
-      }
-    }
-  })
-}
-
-func TestCopyFile(t *testing.T) {
-  testFilesFullPath(t, func(dir string, files []string) {
-    // destination dir
-    td, err := ioutil.TempDir("", "")
-    if err != nil {
-      t.Fatal(err)
-    }
-    defer os.RemoveAll(td)
-
-    tests := []struct {
-      src, dest string
-      error error
-    }{
-      { src: files[2], dest: filepath.Join(td, "file1"), error: nil },
-      { src: files[3], dest: filepath.Join(td, "file3"), error: nil },
-      { src: "audiocc-file-def-dne", dest: files[1],
-        error: errors.New("audiocc-file-def-dne") },
-    }
-
-    for i := range tests {
-      e := copyFile(tests[i].src, tests[i].dest)
-      if e == nil && tests[i].error == nil {
-        break
-      }
-      if e.Error() != tests[i].error.Error() {
-        t.Errorf("Expected %#v, got %#v", tests[i].error.Error(), e.Error())
-      }
-    }
-  })
-}
-
 func TestRenameFolder(t *testing.T) {
-  testFiles := []*testFile{
+  testFiles := []*fsutil.TestFile{
     {"dir1/file1", "abcde"},
     {"dir2/file2", "a"},
     {"dir3/file3", ""},
@@ -362,7 +168,7 @@ func TestRenameFolder(t *testing.T) {
     {"dir6/file6", ""},
   }
 
-  dir := createTestFiles(testFiles, t)
+  dir := fsutil.CreateTestFiles(t, testFiles)
   defer os.RemoveAll(dir)
 
   tests := [][]string{