Increase Budget Result spec to check incompatible investments can't be winners

Why:

* A incompatible investment can't be chosen as a winner
* When a winner investment is marked as incompatible, winnersmust be recalculated and it can't be a winner

How:

* Increasing existing scenarios to include a incompatible investment
* Adding a new scenario where a winner investment gets flagged as incompatible

spec/models/budget/result_spec.rb

@@ -7,29 +7,48 @@ describe Budget::Result do
     let(:group) { create(:budget_group, budget: budget) }
     let(:heading) { create(:budget_heading, group: group, price: 1000) }
 
-    it "calculates a budget's winner investments" do
-      investment1 = create(:budget_investment, :selected, heading: heading, price: 200, ballot_lines_count: 900)
-      investment2 = create(:budget_investment, :selected, heading: heading, price: 300, ballot_lines_count: 800)
-      investment3 = create(:budget_investment, :selected, heading: heading, price: 500, ballot_lines_count: 700)
-      investment4 = create(:budget_investment, :selected, heading: heading, price: 100, ballot_lines_count: 600)
+    context "When there is no winners" do
+      it "calculates the correct winner set" do
+        investment1 = create(:budget_investment, :selected, heading: heading, price: 200, ballot_lines_count: 900, winner: false)
+        investment2 = create(:budget_investment, :selected, heading: heading, price: 300, ballot_lines_count: 800, winner: false)
+        investment3 = create(:budget_investment, :incompatible, heading: heading, price: 500, ballot_lines_count: 700, winner: false)
+        investment4 = create(:budget_investment, :selected, heading: heading, price: 500, ballot_lines_count: 600, winner: false)
+        investment5 = create(:budget_investment, :selected, heading: heading, price: 100, ballot_lines_count: 500, winner: false)
 
-      result = Budget::Result.new(budget, heading)
-      result.calculate_winners
+        Budget::Result.new(budget, heading).calculate_winners
 
-      expect(result.winners).to eq([investment1, investment2, investment3])
+        expect(heading.investments.winners.pluck(:id)).to match_array([investment1.id, investment2.id, investment4.id])
+      end
     end
 
-    it "resets winners before recalculating" do
-      investment1 = create(:budget_investment, :selected, heading: heading, price: 200, ballot_lines_count: 900, winner: true)
-      investment2 = create(:budget_investment, :selected, heading: heading, price: 300, ballot_lines_count: 800, winner: true)
-      investment3 = create(:budget_investment, :selected, heading: heading, price: 500, ballot_lines_count: 700, winner: true)
-      investment4 = create(:budget_investment, :selected, heading: heading, price: 100, ballot_lines_count: 600, winner: true)
+    context "When there are winners" do
+      it "removes winners and recalculates" do
+        investment1 = create(:budget_investment, :winner, heading: heading, price: 200, ballot_lines_count: 900)
+        investment2 = create(:budget_investment, :winner, heading: heading, price: 300, ballot_lines_count: 800)
+        investment3 = create(:budget_investment, :incompatible, heading: heading, price: 500, ballot_lines_count: 700, winner: true)
+        investment4 = create(:budget_investment, :winner, heading: heading, price: 500, ballot_lines_count: 600)
+        investment5 = create(:budget_investment, :winner, heading: heading, price: 100, ballot_lines_count: 500)
 
-      result = Budget::Result.new(budget, heading)
-      result.calculate_winners
+        Budget::Result.new(budget, heading).calculate_winners
 
-      expect(result.winners).to eq([investment1, investment2, investment3])
+        expect(heading.investments.winners.pluck(:id)).to match_array([investment1.id, investment2.id, investment4.id])
+      end
+    end
+
+    context "When a winner is flagged as incompatible" do
+      it "recalculates winners leaving it out" do
+        investment1 = create(:budget_investment, :winner, heading: heading, price: 200, ballot_lines_count: 900)
+        investment2 = create(:budget_investment, :winner, heading: heading, price: 300, ballot_lines_count: 800)
+        investment3 = create(:budget_investment, :winner, heading: heading, price: 500, ballot_lines_count: 700)
+        investment4 = create(:budget_investment, :winner, heading: heading, price: 500, ballot_lines_count: 600)
+        investment5 = create(:budget_investment, :winner, heading: heading, price: 100, ballot_lines_count: 500)
+
+        investment3.incompatible = true
+        investment3.save
+
+        expect(heading.investments.winners.pluck(:id)).to match_array([investment1.id, investment2.id, investment4.id])
+      end
     end
   end
 
-end
+end