how to translate symbol/attributes of models into some french language

I have been using an date picker control, if some one enters text instead of date then there is custom massage that i want to show, I have done it with English language but i am unable to translate it. I have put its translation in fr.yml file but it cant work.

Let me show you my code

invoice.rb **

base.validates_date :due_date, :allow_nil => true
def validates_date(*args)
      options = temporal_validation_options({ :message => _("is an invalid date") }, args)
.
.
      record.errors.add(args, options[:message])
end

**

The string "is an invalid date" get translat开发者_Python百科ed that i done in fr.po file but the word "Due date" also get attached with it and remain untranslated.

I tried to resolve it in my fr.yml file by the following code

fr.yml

  activerecord:   
    errors:
      models:
        invoice: 
      attributes:
        invoice:
        due_date: "date d'échéance"

but what i am getting when i switch to french version is

"Due date est une date invalide " while it should be "date d'échéance est une date invalide "

---

I think the errors is not needed and you have to indent the due_date:

fr:
  activerecord:   
    models:
      invoice: "la facture"
    attributes:
      invoice:
        due_date: "date d'échéance"