Fix booth recounts poll stats discrepancies

Due to technical issues, sometimes users voted in booths and their vote
couldn't be added to the database. So we're including them in the users
with no demographic data.

app/models/poll/stats.rb

@@ -89,6 +89,10 @@ class Poll::Stats
     end
   end
 
+  def total_no_demographic_data
+    super + total_unregistered_booth
+  end
+
   private
 
     def participant_ids
@@ -103,6 +107,14 @@ class Poll::Stats
       @recounts ||= poll.recounts
     end
 
+    def total_registered_booth
+      voters.where(origin: "booth").count
+    end
+
+    def total_unregistered_booth
+      [total_participants_booth - total_registered_booth, 0].max
+    end
+
     stats_cache(*stats_methods)
 
     def stats_cache(key, &block)

spec/models/poll/stats_spec.rb

@@ -186,6 +186,34 @@ describe Poll::Stats do
     end
   end
 
+  describe "#total_no_demographic_data" do
+    before do
+      create(:poll_voter, :from_web, poll: poll, user: create(:user, :level_two, gender: nil))
+    end
+
+    context "more registered participants than participants in recounts" do
+      before do
+        create(:poll_recount, :from_booth, poll: poll, total_amount: 1)
+        2.times { create(:poll_voter, :from_booth, poll: poll) }
+      end
+
+      it "returns registered users with no demographic data" do
+        expect(stats.total_no_demographic_data).to eq 1
+      end
+    end
+
+    context "more participants in recounts than registered participants" do
+      before do
+        create(:poll_recount, :from_booth, poll: poll, total_amount: 3)
+        2.times { create(:poll_voter, :from_booth, poll: poll) }
+      end
+
+      it "returns registered users with no demographic data plus users not registered" do
+        expect(stats.total_no_demographic_data).to eq 2
+      end
+    end
+  end
+
   describe "#channels" do
     context "no participants" do
       it "returns no channels" do