Fix panic in toupper

filehandlers/imgs/img.go

@@ -83,7 +83,7 @@ func (h *UploadImgHandler) metaImg(data *PostMetaData) error {
 
 	img, err := shared.GetImageForOptimization(tee, data.MimeType)
 	finalName := shared.SanitizeFileExt(data.Filename)
-	if errors.Is(err, shared.AlreadyWebPError) {
+	if errors.Is(err, shared.ErrAlreadyWebPError) {
 		h.Cfg.Logger.Infof("(%s) is already webp, skipping encoding", data.Filename)
 		finalName = fmt.Sprintf("%s.webp", finalName)
 		webpReader = tee

shared/img.go

@@ -40,8 +40,8 @@ type Ratio struct {
 	Height int
 }
 
-var AlreadyWebPError = errors.New("image is already webp")
-var IsSvgError = errors.New("image is an svg")
+var ErrAlreadyWebPError = errors.New("image is already webp")
+var ErrIsSvgError = errors.New("image is an svg")
 
 func GetImageForOptimization(r io.Reader, mimeType string) (image.Image, error) {
 	switch mimeType {
@@ -54,7 +54,7 @@ func GetImageForOptimization(r io.Reader, mimeType string) (image.Image, error)
 	case "image/gif":
 		return gif.Decode(r)
 	case "image/webp":
-		return nil, AlreadyWebPError
+		return nil, ErrAlreadyWebPError
 	}
 
 	return nil, fmt.Errorf("(%s) not supported for optimization", mimeType)

shared/util.go

@@ -41,8 +41,12 @@ func FilenameToTitle(filename string, title string) string {
 
 func ToUpper(str string) string {
 	pre := fnameRe.ReplaceAllString(str, " ")
+
 	r := []rune(pre)
-	r[0] = unicode.ToUpper(r[0])
+	if len(r) > 0 {
+		r[0] = unicode.ToUpper(r[0])
+	}
+
 	return string(r)
 }