FIX: handle badge grant for deleted badge (#11558)

app/services/badge_granter.rb

@@ -44,7 +44,7 @@ class BadgeGranter
 
   def grant
     return if @granted_by && !Guardian.new(@granted_by).can_grant_badges?(@user)
-    return unless @badge.enabled?
+    return unless @badge.present? && @badge.enabled?
     return if @badge.badge_grouping_id == BadgeGrouping::GettingStarted && @badge.id != Badge::NewUserOfTheMonth && @user.user_option.skip_new_user_tips
 
     find_by = { badge_id: @badge.id, user_id: @user.id }

spec/services/badge_granter_spec.rb

@@ -208,6 +208,12 @@ describe BadgeGranter do
       expect(Notification.where(user_id: user.id).count).to eq(0)
     end
 
+    it "handles deleted badge" do
+      freeze_time
+      user_badge = BadgeGranter.grant(nil, user, created_at: 1.year.ago)
+      expect(user_badge).to eq(nil)
+    end
+
     it "doesn't grant disabled badges" do
       freeze_time
       badge = Fabricate(:badge, badge_type_id: BadgeType::Bronze, enabled: false)