我不知道为什么这个参数突然出现在我的角色创建页面上。在我添加了权限复选框后，它就出现了。
new.html.erb

<% provide(:title, "Create Roles") %>
<h1 class="dashboard">Create Role</h1>

<div class="row">
 <div class="col-md-6 col-md-offset-3">
  <%= form_with(model: @role, local: true) do |f| %>
  <%= render 'shared/error_messages', object: f.object %>

  <%= f.label :name %>
  <%= f.text_field :name, class: 'form-control' %>

  <%= @permissions.each do |permission|%>
   <%= check_box_tag 'permission_ids[]', permission.id %>
   <%= f.label :permission_name, permission.name %>
  <% end %>

  <%= f.hidden_field :company_id , value: 2%>

  <%= f.submit "Create Role", class: "btn btn-primary bottom" %>
  <% end %>
 </div>
</div>

Parameter show at role create page