我正在尝试向部分内部的用户显示错误。我正在使用以下 simple_form：

<%= simple_form_for :appropriateness_test_results,url: url  do |f| %>
  <%= f.error_notification %>
  <%= f.error_notification message: f.object.errors[:base].to_sentence if f.object.errors[:base].present? %>

  <% randomize_questions.each_with_index.map do |q,i| %>
    <%= f.input "[#{i}][answer]",label: "#{i+1}. #{q[:question]}",collection: q[:answers].map.with_index { |a,i| [a,i.to_s] },as: :radio_buttons,wrapper_class: 'input simple-radio-buttons'%>
  <% end %>
  <%= f.button :submit,'Submit' %>
<% end %>

在 new.html.erb 中呈现的内容

<%= render 'appropriateness_test/shared/form',url: appropriateness_test_step_one_path,randomize_questions: @randomize_questions  %>

控制器内部没有什么特别之处：

module AppropriatenessTest
  class BaseController < SignupBaseController
    before_action :randomize_questions,only: %i[new create]
    include AppropriatenessTest::ParserHelper

    def new
      @appropriateness_test_result = AppropriatenessTestResult.new
    end

    def create
      @appropriateness_test_result = current_user.appropriateness_test_results.new(
        answer: user_answers,)

      if @appropriateness_test_result.save
        redirect_to next_step_path
      else
        render :new,status: :unprocessable_entity
      end
    end

# user_answers output 
{"0"=>{"id"=>"21","answer"=>""},"1"=>{"id"=>"22","2"=>{"id"=>"23","3"=>{"id"=>"18","4"=>{"id"=>"19","5"=>{"id"=>"20","answer"=>""}}

这是注册过程中的步骤之一。但是我无法使用此表单显示页面，因为出现以下错误：

undefined method errors for nil:NilClass
Extracted source (around line #3):
1 <%= simple_form_for :appropriateness_test_results,url: url  do |f| %>
2 <%= f.error_notification %>
3  <%= f.error_notification message: f.object.errors[:base].to_sentence if f.object.errors[:base].present? %>
4
5  <% randomize_questions.each_with_index.map do |q,i| %>
6    <%= f.input "[#{i}][answer]",wrapper_class: 'input simple-radio-buttons'%>

当我删除负责显示错误的行时，它运行良好，但很自然地，我无法向用户显示验证错误。所以问题是如何显示错误并避免这种 undefined method 错误？