Order translations using ruby

Joining the translations table caused duplicate records to appear.
Ordering with SQL is simply too hard because we need to consider
fallback locales.

Thanks Senén for providing most of the tests in the poll spec.

spec/models/poll/poll_spec.rb

@@ -359,4 +359,58 @@ describe Poll do
 
   end
 
+  describe "#sort_for_list" do
+    it "returns polls sorted by name ASC" do
+      starts_at = Time.current + 1.day
+      poll1 = create(:poll, geozone_restricted: true, starts_at: starts_at, name: "Zzz...")
+      poll2 = create(:poll, geozone_restricted: true, starts_at: starts_at, name: "Mmmm...")
+      poll3 = create(:poll, geozone_restricted: true, starts_at: starts_at, name: "Aaaaah!")
+
+      expect(Poll.sort_for_list).to eq [poll3, poll2, poll1]
+    end
+
+    it "returns not geozone restricted polls first" do
+      starts_at = Time.current + 1.day
+      poll1 = create(:poll, geozone_restricted: false, starts_at: starts_at, name: "Zzz...")
+      poll2 = create(:poll, geozone_restricted: true, starts_at: starts_at, name: "Aaaaaah!")
+
+      expect(Poll.sort_for_list).to eq [poll1, poll2]
+    end
+
+    it "returns polls earlier to start first" do
+      starts_at = Time.current + 1.day
+      poll1 = create(:poll, geozone_restricted: false, starts_at: starts_at - 1.hour, name: "Zzz...")
+      poll2 = create(:poll, geozone_restricted: false, starts_at: starts_at, name: "Aaaaah!")
+
+      expect(Poll.sort_for_list).to eq [poll1, poll2]
+    end
+
+    it "returns polls with multiple translations only once" do
+      create(:poll, name_en: "English", name_es: "Spanish")
+
+      expect(Poll.sort_for_list.count).to eq 1
+    end
+
+    context "fallback locales" do
+      before do
+        allow(I18n.fallbacks).to receive(:[]).and_return([:es])
+        Globalize.set_fallbacks_to_all_available_locales
+      end
+
+      it "orders by name considering fallback locales" do
+        starts_at = Time.current + 1.day
+        poll1 = create(:poll, starts_at: starts_at, name: "Charlie")
+        poll2 = create(:poll, starts_at: starts_at, name: "Delta")
+        poll3 = Globalize.with_locale(:es) do
+          create(:poll, starts_at: starts_at, name: "Zzz...", name_fr: "Aaaah!")
+        end
+        poll4 = Globalize.with_locale(:es) do
+          create(:poll, starts_at: starts_at, name: "Bravo")
+        end
+
+        expect(Poll.sort_for_list.count).to eq 4
+        expect(Poll.sort_for_list).to eq [poll4, poll1, poll2, poll3]
+      end
+    end
+  end
 end