saving new turn

pkg/repo/fs/fs.go

@@ -75,6 +75,10 @@ func (f *fs) Lock() (func() error, error) {
 	return unlock, nil
 }
 
+func (f *fs) Exist(path string) (bool, error) {
+	return fileExists(filepath.Join(f.root, path))
+}
+
 func (f *fs) Write(path string, v encoding.BinaryMarshaler) error {
 	if v == nil {
 		return errors.New("cant't marshal from nil object")

pkg/repo/fs/fs_test.go

@@ -33,6 +33,27 @@ func TestLock(t *testing.T) {
 	assert.False(t, exists, "lock file must be removed")
 }
 
+func TestExist(t *testing.T) {
+	root, cleanup := createWorkDir(t)
+	defer cleanup()
+
+	fileName := "some-file.ext"
+	if err := os.WriteFile(filepath.Join(root, fileName), []byte{1, 2, 3, 4}, os.ModePerm); err != nil {
+		t.Fatal(err)
+	}
+
+	fs, err := NewFileStorage(root)
+	assert.NoError(t, err, "create file storage")
+
+	exist, err := fs.Exist(fileName)
+	assert.NoError(t, err)
+	assert.True(t, exist)
+
+	exist, err = fs.Exist("random/path")
+	assert.NoError(t, err)
+	assert.False(t, exist)
+}
+
 func TestWrite(t *testing.T) {
 	root, cleanup := createWorkDir(t)
 	defer cleanup()