Use system specs instead of feature specs

We get rid of database cleaner, and JavaScript tests are faster because
between tests we now rollback transactions instead of truncating the
database.

spec/system/localization_spec.rb

@@ -0,0 +1,91 @@
+require "rails_helper"
+
+describe "Localization" do
+  scenario "Wrong locale" do
+    I18n.with_locale(:es) do
+      create(:widget_card, title: "Bienvenido a CONSUL",
+                           description: "Software libre para la participación ciudadana.",
+                           link_text: "Más información",
+                           link_url: "http://consulproject.org/",
+                           header: true)
+    end
+
+    visit root_path(locale: :es)
+    visit root_path(locale: :klingon)
+
+    expect(page).to have_text("Bienvenido a CONSUL")
+  end
+
+  scenario "Available locales appear in the locale switcher" do
+    visit "/"
+
+    within(".locale-form .js-location-changer") do
+      expect(page).to have_content "Español"
+      expect(page).to have_content "English"
+    end
+  end
+
+  scenario "The current locale is selected" do
+    visit "/"
+    expect(page).to have_select("locale-switcher", selected: "English")
+  end
+
+  scenario "Changing the locale", :js do
+    visit "/"
+    expect(page).to have_content("Language")
+
+    select("Español", from: "locale-switcher")
+    expect(page).to have_content("Idioma")
+    expect(page).not_to have_content("Language")
+    expect(page).to have_select("locale-switcher", selected: "Español")
+  end
+
+  scenario "Keeps query parameters while using protected redirects", :js do
+    visit "/debates?order=created_at&host=evil.dev"
+
+    select("Español", from: "locale-switcher")
+
+    expect(current_host).to eq "http://127.0.0.1"
+    expect(page).to have_current_path "/debates?locale=es&order=created_at"
+  end
+
+  context "Only one locale" do
+    before do
+      allow(I18n).to receive(:available_locales).and_return([:en])
+      I18n.reload!
+    end
+
+    after { I18n.reload! }
+
+    scenario "Locale switcher not present" do
+      visit "/"
+      expect(page).not_to have_content("Language")
+      expect(page).not_to have_css("div.locale")
+    end
+  end
+
+  context "Missing language names" do
+    let!(:default_enforce) { I18n.enforce_available_locales }
+    let!(:default_locales) { I18n.available_locales.dup }
+
+    before do
+      I18n.enforce_available_locales = false
+      I18n.available_locales = default_locales + [:wl]
+      I18n.locale = :wl
+    end
+
+    after do
+      I18n.enforce_available_locales = default_enforce
+      I18n.available_locales = default_locales
+      I18n.locale = I18n.default_locale
+    end
+
+    scenario "Available locales without language translation display locale key" do
+      visit "/"
+
+      within(".locale-form .js-location-changer") do
+        expect(page).to have_content "wl"
+      end
+    end
+  end
+end