Move #selected_options to the only relevant model

app/models/champs/multiple_drop_down_list_champ.rb

@@ -2,7 +2,11 @@ class Champs::MultipleDropDownListChamp < Champ
   before_save :format_before_save
 
   def search_terms
-    drop_down_list.selected_options(self)
+    selected_options
+  end
+
+  def selected_options
+    value.blank? ? [] : JSON.parse(value)
   end
 
   private
@@ -20,10 +24,10 @@ class Champs::MultipleDropDownListChamp < Champ
   end
 
   def string_value
-    drop_down_list.selected_options(self).join(', ')
+    selected_options.join(', ')
   end
 
   def value_for_export
-    drop_down_list.selected_options(self).join(', ')
+    selected_options.join(', ')
   end
 end

app/models/drop_down_list.rb

@@ -10,10 +10,6 @@ class DropDownList < ApplicationRecord
     options.select { |v| (v =~ /^--.*--$/).present? }
   end
 
-  def selected_options(champ)
-    champ.value.blank? ? [] : multiple ? JSON.parse(champ.value) : [champ.value]
-  end
-
   def multiple
     type_de_champ.type_champ == TypeDeChamp.type_champs.fetch(:multiple_drop_down_list)
   end

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

@@ -1,7 +1,7 @@
 - if champ.drop_down_list && champ.drop_down_list.options.any?
   = form.select :value,
       champ.drop_down_list.options,
-      { selected: champ.drop_down_list.selected_options(champ),
+      { selected: champ.selected_options,
         disabled: champ.drop_down_list.disabled_options },
       multiple: true,
       class: 'select2'