add flash alert if email field empty

app/controllers/concerns/create_avis_concern.rb

@@ -4,6 +4,11 @@ module CreateAvisConcern
   private
 
   def create_avis_from_params(dossier, instructeur_or_expert, confidentiel = false)
+    if create_avis_params[:emails].empty?
+      flash.alert = t('activerecord.errors.models.email.empty')
+      return Avis.new(create_avis_params)
+    end
+
     confidentiel ||= create_avis_params[:confidentiel]
     # Because of a limitation of the email_field rails helper,
     # the :emails parameter is a 1-element array.

config/locales/models/avis/en.yml

@@ -7,6 +7,10 @@ en:
         answer: "Answer"
         claimant: Claimant
         confidentiel: Confidential
+    errors:
+      models:
+        email:
+          empty: Email field can not be empty
   helpers:
     label:
       invite_linked_dossiers:

config/locales/models/avis/fr.yml

@@ -7,6 +7,10 @@ fr:
         answer: "Réponse"
         claimant: Demandeur
         confidentiel: confidentiel
+    errors:
+      models:
+        email:
+          empty: Le champ email ne peut pas être vide
   helpers:
     label:
       invite_linked_dossiers:

spec/controllers/instructeurs/dossiers_controller_spec.rb

@@ -628,6 +628,17 @@ describe Instructeurs::DossiersController, type: :controller do
         it { expect(dossier.last_avis_updated_at).to eq(nil) }
       end
 
+      context "with no email" do
+        let(:emails) { "" }
+
+        before { subject }
+
+        it { expect(response).to render_template :avis }
+        it { expect(flash.alert).to eq("Le champ email ne peut pas être vide") }
+        it { expect { subject }.not_to change(Avis, :count) }
+        it { expect(dossier.last_avis_updated_at).to eq(nil) }
+      end
+
       context 'with multiple emails' do
         let(:emails) { "[\"toto.fr\",\"titi@titimail.com\"]" }