Add winner method to match

app/models/match.rb

@@ -19,6 +19,11 @@ class Match < ApplicationRecord
     stage ? stage.owner : group.owner
   end
 
+  def winner
+    evaluate_winner
+    # This should maybe be cached or put into db
+  end
+
   private
 
   def evaluate_winner

spec/models/match_spec.rb

@@ -43,6 +43,23 @@ RSpec.describe Match, type: :model do
     end
   end
 
+  context '#winner' do
+    before do
+      @undecided_match = create(:undecided_group_match)
+      @decided_match = create(:decided_playoff_match)
+    end
+
+    it 'returns a winner Team for a decided match' do
+      winner = @decided_match.winner
+      expect(winner).to be_a Team
+    end
+
+    it 'returns nil for an undecided match' do
+      winner = @undecided_match.winner
+      expect(winner).to be(nil)
+    end
+  end
+
   context '#teams' do
     before do
       @playoff_match = create(:running_playoff_match)