Add tests for file util

internal/util/file_test.go

@@ -1,6 +1,7 @@
 package util
 
 import (
+	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -11,10 +12,46 @@ func TestExists(t *testing.T) {
 	assert.False(t, Exists("./foo.jpg"))
 }
 
-func TestExpandedFilename(t *testing.T) {
-	filename := ExpandedFilename("./testdata/test.jpg")
+func TestOverwrite(t *testing.T) {
+	data := make([]byte, 3)
+	data[1] = 3
+	data[2] = 8
+	tmpPath := "./testdata/_tmp"
+	os.Mkdir(tmpPath, 0777)
 
-	assert.IsType(t, "", filename)
+	defer os.RemoveAll(tmpPath)
+	result := Overwrite("./testdata/_tmp/notyetexisting.jpg", data)
+	assert.FileExists(t, "./testdata/_tmp/notyetexisting.jpg")
+	t.Log(result)
 
-	t.Logf("ExpandedFilename: %s", filename)
+}
+
+func TestExpandedFilename(t *testing.T) {
+	t.Run("test.jpg", func(t *testing.T) {
+		filename := ExpandedFilename("./testdata/test.jpg")
+		assert.Contains(t, filename, "/testdata/test.jpg")
+		assert.IsType(t, "", filename)
+	})
+	t.Run("empty filename", func(t *testing.T) {
+		filename := ExpandedFilename("")
+		assert.Equal(t, "", filename)
+		assert.IsType(t, "", filename)
+	})
+	t.Run("~ in filename", func(t *testing.T) {
+		filename := ExpandedFilename("~/test.jpg")
+		assert.Equal(t, "/root/test.jpg", filename)
+		assert.IsType(t, "", filename)
+	})
+}
+
+func TestDirectoryIsEmpty(t *testing.T) {
+	t.Run("not empty path", func(t *testing.T) {
+		assert.Equal(t, false, DirectoryIsEmpty("./testdata"))
+	})
+	t.Run("not existing path", func(t *testing.T) {
+		assert.Equal(t, false, DirectoryIsEmpty("./xxx"))
+	})
+	t.Run("photo-lover", func(t *testing.T) {
+		assert.Equal(t, true, DirectoryIsEmpty("./testdata/emptyDir"))
+	})
 }