Add tests for filesystem driver

Gopkg.lock

@@ -350,6 +350,7 @@
     "github.com/spf13/viper",
     "github.com/stretchr/testify/assert",
     "github.com/stretchr/testify/mock",
+    "github.com/stretchr/testify/require",
     "github.com/stretchr/testify/suite",
     "github.com/tevino/abool",
     "github.com/thedevsaddam/govalidator",

db/fs/fs.go

@@ -17,10 +17,6 @@ type Filesystem struct {
 }
 
 func (f *Filesystem) FindCapeByUsername(username string) (*model.Cape, error) {
-	if username == "" {
-		return nil, nil
-	}
-
 	capePath := path.Join(f.path, strings.ToLower(username)+".png")
 	file, err := os.Open(capePath)
 	if err != nil {

db/fs/fs_integration_test.go

@@ -0,0 +1,56 @@
+package fs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestNew(t *testing.T) {
+	fs, err := New("base/path")
+	require.Nil(t, err)
+	require.Equal(t, "base/path", fs.path)
+}
+
+func TestFilesystem(t *testing.T) {
+	t.Run("FindCapeByUsername", func(t *testing.T) {
+		dir, err := ioutil.TempDir("", "capes")
+		if err != nil {
+			panic(fmt.Errorf("cannot crete temp directory for tests: %w", err))
+		}
+		defer os.RemoveAll(dir)
+
+		t.Run("exists cape", func(t *testing.T) {
+			file, err := os.Create(path.Join(dir, "username.png"))
+			if err != nil {
+				panic(fmt.Errorf("cannot create temp skin for tests: %w", err))
+			}
+			defer os.Remove(file.Name())
+
+			fs, _ := New(dir)
+			cape, err := fs.FindCapeByUsername("username")
+			require.Nil(t, err)
+			require.NotNil(t, cape)
+			capeFile, _ := cape.File.(*os.File)
+			require.Equal(t, file.Name(), capeFile.Name())
+		})
+
+		t.Run("not exists cape", func(t *testing.T) {
+			fs, _ := New(dir)
+			cape, err := fs.FindCapeByUsername("username")
+			require.Nil(t, err)
+			require.Nil(t, cape)
+		})
+
+		t.Run("empty username", func(t *testing.T) {
+			fs, _ := New(dir)
+			cape, err := fs.FindCapeByUsername("")
+			require.Nil(t, err)
+			require.Nil(t, cape)
+		})
+	})
+}