dossier: send deletion email also to the following gestionnaires

app/models/dossier.rb

@@ -276,8 +276,12 @@ class Dossier < ApplicationRecord
     now = Time.now
     deleted_dossier = DeletedDossier.create!(dossier_id: id, procedure: procedure, state: state, deleted_at: now)
     update(hidden_at: now)
+
+    administration_emails = followers_gestionnaires.present? ? followers_gestionnaires.pluck(:email) : [procedure.administrateur.email]
+    administration_emails.each do |email|
+      DossierMailer.notify_deletion_to_administration(deleted_dossier, email).deliver_later
+    end
     DossierMailer.notify_deletion_to_user(deleted_dossier, user.email).deliver_later
-    DossierMailer.notify_deletion_to_administration(deleted_dossier, procedure.administrateur.email).deliver_later
   end
 
   private

spec/models/dossier_spec.rb

@@ -828,9 +828,29 @@ describe Dossier do
       expect(deleted_dossier.deleted_at).to be_present
     end
 
-    it 'sends notification emails' do
+    it 'notifies the user' do
       expect(DossierMailer).to have_received(:notify_deletion_to_user).with(deleted_dossier, dossier.user.email)
-      expect(DossierMailer).to have_received(:notify_deletion_to_administration).with(deleted_dossier, dossier.procedure.administrateur.email)
+    end
+
+    context 'where gestionnaires are following the dossier' do
+      let(:dossier) { create(:dossier, :followed) }
+      let!(:non_following_gestionnaire) do
+        non_following_gestionnaire = create(:gestionnaire)
+        non_following_gestionnaire.procedures << dossier.procedure
+        non_following_gestionnaire
+      end
+
+      it 'notifies the following gestionnaires' do
+        expect(DossierMailer).to have_received(:notify_deletion_to_administration).once
+        expect(DossierMailer).to have_received(:notify_deletion_to_administration).with(deleted_dossier, dossier.followers_gestionnaires.first.email)
+      end
+    end
+
+    context 'when there are no following gestionnaires' do
+      it 'notifies the procedure administrateur' do
+        expect(DossierMailer).to have_received(:notify_deletion_to_administration).once
+        expect(DossierMailer).to have_received(:notify_deletion_to_administration).with(deleted_dossier, dossier.procedure.administrateur.email)
+      end
     end
   end