[#1421] Move same_hour / same_minute to typed champ

app/models/champ.rb

@@ -32,27 +32,10 @@ class Champ < ApplicationRecord
     !private?
   end
 
-  def same_hour?(num)
-    same_date? num, '%H'
-  end
-
-  def same_minute?(num)
-    same_date? num, '%M'
-  end
-
   def mandatory_and_blank?
     mandatory? && value.blank?
   end
 
-  def same_date?(num, compare)
-    if type_champ == 'datetime' && value.present?
-      if value.to_datetime.strftime(compare) == num
-        return true
-      end
-    end
-    false
-  end
-
   def self.regions
     JSON.parse(Carto::GeoAPI::Driver.regions).sort_by { |e| e['nom'] }.pluck("nom")
   end

app/models/champs/datetime_champ.rb

@@ -1,8 +1,20 @@
 class Champs::DatetimeChamp < Champ
   before_save :format_before_save
 
+  def same_hour?(num)
+    same_date?(num, '%H')
+  end
+
+  def same_minute?(num)
+    same_date?(num, '%M')
+  end
+
   private
 
+  def same_date?(num, compare)
+    return value.present? && value.to_datetime.strftime(compare) == num
+  end
+
   def format_before_save
     if (value =~ /=>/).present?
       self.value =