perf(usager): cache tabs with a simple and fast cache_key

Plutôt que d'include dans la cache_key tous les scopes utilisés par l'onglet,
(ce qui provquerait une requête par scope),
on le base simplement sur les dossiers & invitations.
Les deleted dossiers sont inclus indirectement car ça correspond à la
suppression (N-1) d'un dossier.

app/views/users/dossiers/index.html.haml

@@ -25,6 +25,7 @@
           = render Dossiers::UserProcedureFilterComponent.new(procedures_for_select: @procedures_for_select)
 
     - if @search_terms.blank?
+      - cache([current_user.id, @statut, current_user.dossiers, current_user.dossiers_invites], expires_in: 1.hour) do
         %nav.fr-tabs{ role: 'navigation', 'aria-label': t('views.users.dossiers.secondary_menu') }
           %ul.fr-tabs__list{ role: 'tablist' }
             - if @user_dossiers.present?

spec/views/users/dossiers/index.html.haml_spec.rb

@@ -3,15 +3,15 @@ describe 'users/dossiers/index', type: :view do
   let(:dossier_brouillon) { create(:dossier, state: Dossier.states.fetch(:brouillon), user: user) }
   let(:dossier_en_construction) { create(:dossier, state: Dossier.states.fetch(:en_construction), user: user) }
   let(:dossier_termine) { create(:dossier, state: Dossier.states.fetch(:accepte), user: user) }
-  let(:user_dossiers) { [dossier_brouillon, dossier_en_construction, dossier_termine] }
   let(:dossiers_invites) { [] }
+  let(:user_dossiers) { Kaminari.paginate_array([dossier_brouillon, dossier_en_construction, dossier_termine]).page(1) }
   let(:statut) { 'en-cours' }
   let(:filter) { DossiersFilter.new(user, ActionController::Parameters.new(random_param: 'random_param')) }
 
-  before do
+  before do |config|
     allow(view).to receive(:new_demarche_url).and_return('#')
     allow(controller).to receive(:current_user) { user }
-    assign(:user_dossiers, Kaminari.paginate_array(user_dossiers).page(1))
+    assign(:user_dossiers, user_dossiers)
     assign(:dossiers_invites, Kaminari.paginate_array(dossiers_invites).page(1))
     assign(:dossiers_supprimes_recemment, Kaminari.paginate_array(user_dossiers).page(1))
     assign(:dossiers_supprimes_definitivement, Kaminari.paginate_array(user_dossiers).page(1))
@@ -22,7 +22,8 @@ describe 'users/dossiers/index', type: :view do
     assign(:statut, statut)
     assign(:filter, filter)
     assign(:all_dossiers_uniq_procedures_count, 0)
-    render
+
+    render if !config.metadata[:caching]
   end
 
   it 'affiche les dossiers' do
@@ -101,4 +102,62 @@ describe 'users/dossiers/index', type: :view do
       expect(rendered).to have_text("Supprimer le dossier")
     end
   end
+
+  context 'caching', caching: true do
+    it "works" do
+      expect(user_dossiers).to receive(:present?).once
+      2.times { render; user.reload }
+    end
+
+    it "cache key depends on statut" do
+      expect(user_dossiers).to receive(:present?).twice
+      render
+
+      assign(:statut, "termines")
+      user.reload
+
+      render
+    end
+
+    it "cache key depends on dossier updated_at" do
+      expect(user_dossiers).to receive(:present?).twice
+      render
+
+      dossier_termine.touch
+      user.reload
+
+      render
+    end
+
+    it "cache key depends on dossiers list" do
+      render
+      expect(rendered).to have_text(/3\s+en cours/)
+
+      assign(:user_dossiers, Kaminari.paginate_array(user_dossiers.concat([create(:dossier, :en_construction, user: user)])).page(1))
+      user.reload
+
+      render
+      expect(rendered).to have_text(/4\s+en cours/)
+    end
+
+    it "cache key dpeends on dossier invites" do
+      expect(user_dossiers).to receive(:present?).twice
+      render
+
+      create(:invite, user:)
+      user.reload
+
+      render
+    end
+
+    it "cache key depends on dossier deletion" do
+      expect(user_dossiers).to receive(:present?).twice
+      render
+
+      dossier_termine.expired_keep_track_and_destroy!
+      user.reload
+
+      render
+    end
+  end
 end