Adds a custom validator for dates (#12736).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11124 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/core_ext/active_record.rb

@@ -38,3 +38,14 @@ module ActiveRecord
     end
   end
 end
+
+class DateValidator < ActiveModel::EachValidator
+  def validate_each(record, attribute, value)
+    before_type_cast = record.attributes_before_type_cast[attribute.to_s]
+    if before_type_cast.is_a?(String) && before_type_cast.present?
+      unless before_type_cast =~ /\A\d{4}-\d{2}-\d{2}\z/ && value
+        record.errors.add attribute, :not_a_date
+      end
+    end
+  end
+end