[#1421] linked dropdwon user view

app/assets/javascripts/new_design/champs/linked_drop_down_list.js

@@ -0,0 +1,30 @@
+document.addEventListener('turbolinks:load', function() {
+  var masters, i, master, slave, slaveOptions;
+
+  masters = document.querySelectorAll('select[data-slave-options]');
+  for (i = 0; i < masters.length; i++) {
+    master = masters[i];
+    slave = document.querySelector('select[data-slave-id="' + master.dataset.masterId + '"]');
+    slaveOptions = JSON.parse(master.dataset.slaveOptions);
+
+    master.addEventListener('change', function(e) {
+      var option, options, element;
+
+      while ((option = slave.firstChild)) {
+        slave.removeChild(option);
+      }
+
+      options = slaveOptions[e.target.value];
+
+      for (i = 0; i < options.length; i++) {
+        option = options[i];
+        element = document.createElement("option");
+        element.textContent = option;
+        element.value = option;
+        slave.appendChild(element);
+      }
+
+      slave.selectedIndex = 0;
+    });
+  }
+});

app/controllers/new_user/dossiers_controller.rb

@@ -145,7 +145,7 @@ module NewUser
     def champs_params
       params.permit(dossier: {
         champs_attributes: [
-          :id, :value, :piece_justificative_file, value: [],
+          :id, :value, :master_value, :slave_value, :piece_justificative_file, value: [],
           etablissement_attributes: Champs::SiretChamp::ETABLISSEMENT_ATTRIBUTES
         ]
       })

app/views/shared/dossiers/editable_champs/_linked_drop_down_list.html.haml

@@ -0,0 +1,10 @@
+- if champ.drop_down_list && champ.drop_down_list.options.any?
+  - champ_id = champ.object_id
+  = form.select :master_value,
+    champ.master_options,
+    { required: champ.mandatory? },
+    { data: { "slave-options" => champ.slave_options, "master-id" => champ_id } }
+  = form.select :slave_value,
+    champ.slave_options[champ.master_value],
+    { required: champ.mandatory? },
+    { data: { "slave-id" => champ_id } }

spec/features/new_user/linked_dropdown_spec.rb

@@ -0,0 +1,76 @@
+require 'spec_helper'
+
+feature 'linked dropdown lists' do
+  let(:password) { 'secret_password' }
+  let!(:user) { create(:user, password: password) }
+
+  let(:list_items) do
+    <<~END_OF_LIST
+      --Master 1--
+      Slave 1.1
+      Slave 1.2
+      --Master 2--
+      Slave 2.1
+      Slave 2.2
+      Slave 2.3
+    END_OF_LIST
+  end
+  let(:drop_down_list) { create(:drop_down_list, value: list_items) }
+  let(:type_de_champ) { create(:type_de_champ_linked_drop_down_list, libelle: 'linked dropdown', drop_down_list: drop_down_list) }
+
+  let!(:procedure) do
+    p = create(:procedure, :published, :for_individual)
+    p.types_de_champ << type_de_champ
+    p
+  end
+
+  let(:user_dossier) { user.dossiers.first }
+
+  scenario 'change master value, slave options are updated', js: true do
+    log_in(user.email, password, procedure)
+
+    fill_individual
+
+    # Select a master value
+    select('Master 2', from: master_id_for('linked dropdown'))
+
+    # Slave menu reflects chosen master value
+    expect(page).to have_select(slave_id_for('linked dropdown'), options: ['', 'Slave 2.1', 'Slave 2.2', 'Slave 2.3'])
+
+    # Select another master value
+    select('Master 1', from: master_id_for('linked dropdown'))
+
+    # Slave menu gets updated
+    expect(page).to have_select(slave_id_for('linked dropdown'), options: ['', 'Slave 1.1', 'Slave 1.2'])
+  end
+
+  private
+
+  def log_in(email, password, procedure)
+    visit "/commencer/#{procedure.procedure_path.path}"
+    expect(page).to have_current_path(new_user_session_path)
+
+    fill_in 'user_email', with: email
+    fill_in 'user_password', with: password
+    click_on 'Se connecter'
+    expect(page).to have_current_path(identite_dossier_path(user_dossier))
+  end
+
+  def fill_individual
+    fill_in('individual_prenom', with: 'prenom')
+    fill_in('individual_nom', with: 'nom')
+    check 'dossier_autorisation_donnees'
+    click_on 'Continuer'
+    expect(page).to have_current_path(modifier_dossier_path(user_dossier))
+  end
+
+  def master_id_for(libelle)
+    find(:xpath, ".//label[contains(text()[normalize-space()], '#{libelle}')]")[:for]
+  end
+
+  def slave_id_for(libelle)
+    master_id = master_id_for(libelle)
+    link = find("\##{master_id}")['data-master-id']
+    find("[data-slave-id=\"#{link}\"]")['id']
+  end
+end