Change hash field to Option[String].

src/main/scala/gitbucket/core/controller/IndexController.scala

@@ -19,12 +19,12 @@ trait IndexControllerBase extends ControllerBase {
   self: RepositoryService with ActivityService with AccountService with RepositorySearchService
     with UsersAuthenticator with ReferrerAuthenticator =>
 
-  case class SignInForm(userName: String, password: String, hash: String)
+  case class SignInForm(userName: String, password: String, hash: Option[String])
 
   val signinForm = mapping(
     "userName" -> trim(label("Username", text(required))),
     "password" -> trim(label("Password", text(required))),
-    "hash" -> text()
+    "hash" -> trim(optional(text()))
   )(SignInForm.apply)
 
 //  val searchForm = mapping(
@@ -87,7 +87,7 @@ trait IndexControllerBase extends ControllerBase {
   /**
    * Set account information into HttpSession and redirect.
    */
-  private def signin(account: Account, hash: String) = {
+  private def signin(account: Account, hash: Option[String]) = {
     session.setAttribute(Keys.Session.LoginAccount, account)
     updateLastLoginDate(account.userName)
 
@@ -99,7 +99,7 @@ trait IndexControllerBase extends ControllerBase {
       if(redirectUrl.stripSuffix("/") == request.getContextPath){
         redirect("/")
       } else {
-        redirect(redirectUrl + hash)
+        redirect(redirectUrl + hash.getOrElse(""))
       }
     }.getOrElse {
       redirect("/")