为什么SimpleForm不适用于日期字段？

Question

我正在使用持续的simple_form gem并遵循simple_form表单呈现错误：

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

以下是edit视图和Student：https://gist.github.com/ccbef8a0fb67a164efee

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

gem github页面上的问题：https://github.com/plataformatec/simple_form/issues/695#issuecomment-10495237

Rails：3.2.8 SF：2.0.3

如何解决这个问题？

Answer 1

该问题的解决方案如下： https://github.com/plataformatec/simple_form/issues/695#issuecomment-10495237