爲什麼SimpleForm不適用於日期字段？

Question

我使用歷時simple_form寶石及以下simple_form形式呈現錯誤：

cant`t convert Symbol into String

= simple_form_for @student, html: { multipart: true, class: 'form-horizontal' } do |f| 
    = f.input :email, disabled: true 
    = f.input :birthdate 
    = f.input :address_number 
    = f.input :address_street 
    = f.button :submit, class: "btn btn-primary pull-right" 

# == Schema Information 
# 
# Table name: students 
# 
# address_number   :string(255) 
# address_postalcode  :string(255) 
# address_street   :string(255) 
# approved    :boolean   default(FALSE), not null 
# ask_counter    :integer   default(0) 
# authentication_token :string(255) 
# birthdate    :date 

這裏是edit觀點和Student：https://gist.github.com/ccbef8a0fb67a164efee

我的Gemfile：https://gist.github.com/00ec5a897a6cb88e0bab

發行寶石github上頁：https://github.com/plataformatec/simple_form/issues/695#issuecomment-10495237

Rails的：3.2.8 SF：2.0.3

如何解決呢？

Answer 1

該問題的解決方案在這裏： https://github.com/plataformatec/simple_form/issues/695#issuecomment-10495237