fix tests

app/controllers/comment_votes_controller.rb

@@ -8,7 +8,7 @@ class CommentVotesController < ApplicationController
     @comment_vote = @comment.vote!(params[:score])
   rescue CommentVote::Error, ActiveRecord::RecordInvalid => x
     @error = x
-    render status: 500
+    render status: 422
   end
 
   def destroy
@@ -16,6 +16,6 @@ class CommentVotesController < ApplicationController
     @comment.unvote!
   rescue CommentVote::Error => x
     @error = x
-    render status: 500
+    render status: 422
   end
 end

app/views/comment_votes/create.json.erb

@@ -1,4 +1,6 @@
-<% if @comment_vote.errors.any? %>
+<% if @error %>
+  {"success": false, "errors": <%= @error.to_s.to_json.html_safe %>}
+<% elsif @comment_vote.errors.any? %>
   {"success": false, "errors": <%= @comment_vote.errors.full_messages.to_json.html_safe %>}
 <% else %>
   {"success": true}