<%= form_for(resource, as: resource_name, url: session_path(resource_name)) do |f| %>
  <div><%= f.label :email %><br />
  <%= f.email_field :email, autofocus: true %></div>
  <div><%= f.label :password %><br />
    <%= f.password_field :password, autocomplete: "off" %></div>
  <div><%= f.submit "Sign in" %></div>
<% end %>

module ApplicationHelper
  def resource_name
    :user
  end

  def resource
    @resource ||= User.new
  end

  def devise_mapping
    @devise_mapping ||= Devise.mappings[:user]
  end
end