check rename condition in the service method instead of outside

Author: lunny

routers/web/admin/users.go

@@ -347,7 +347,7 @@ func EditUserPost(ctx *context.Context) {
 		return
 	}
 
-	if form.UserName != "" && form.UserName != u.Name {
+	if form.UserName != "" {
 		if err := user_service.RenameUser(ctx, u, form.UserName); err != nil {
 			switch {
 			case user_model.IsErrUserIsNotLocal(err):

services/user/user.go

@@ -32,6 +32,10 @@ import (
 
 // RenameUser renames a user
 func RenameUser(ctx context.Context, u *user_model.User, newUserName string) error {
+	if newUserName == u.Name {
+		return nil
+	}
+
 	// Non-local users are not allowed to change their username.
 	if !u.IsOrganization() && !u.IsLocal() {
 		return user_model.ErrUserIsNotLocal{
@@ -40,10 +44,6 @@ func RenameUser(ctx context.Context, u *user_model.User, newUserName string) err
 		}
 	}
 
-	if newUserName == u.Name {
-		return nil
-	}
-
 	if err := user_model.IsUsableUsername(newUserName); err != nil {
 		return err
 	}