From 78acebcd70163cf74c20395f11a8f4612d8f2584 Mon Sep 17 00:00:00 2001
From: Dominic Grimm <dominic.grimm@gmail.com>
Date: Tue, 8 Mar 2022 10:54:30 +0100
Subject: [PATCH] Fix vote teacher selection can be empty

---
 docker/backend/src/backend/api/schema/mutation.cr | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docker/backend/src/backend/api/schema/mutation.cr b/docker/backend/src/backend/api/schema/mutation.cr
index 6fce16d..358ce43 100644
--- a/docker/backend/src/backend/api/schema/mutation.cr
+++ b/docker/backend/src/backend/api/schema/mutation.cr
@@ -143,6 +143,8 @@ module Backend
         def create_vote(context : Context, input : VoteCreateInput) : Vote
           context.student!
 
+          raise "Teacher selection can't be empty" if input.teacher_ids.empty?
+
           skif = context.external.as(Db::Student).skif
           input.teacher_ids.each do |id|
             teacher = Db::Teacher.find(id)