RSpec Looking for spree.admin_items_path (Raise admin_items_path undefined)

index.html.erb

<h1>Featured Items</h1>

<table>
  <thead>
    <tr>
      <th>IMAGE</th>
      <th>Name</th>
      <th>Description</th>
      <th>SHOW</th>
      <th>EDIT</th>
      <th>DELETE</th>
    </tr>
  </thead>

  <tbody>
    <% @items.each do |item| %>
      <tr>
        <td><%= image_tag item.marketing_image, :style => "height: 50px;" %></td>
        <td><%= item.name %></td>
        <td><%= item.description %></td>
        <td><%= link_to 'Show', admin_item_path(item) %></td>
        <td><%= link_to 'Edit', edit_admin_item_path(item) %></td>
        <td><%= link_to 'Destroy', admin_item_path(item), method: :delete, data: { confirm: 'Are you sure?' } %></td>
      </tr>
    <% end %>
  </tbody>
</table>

<br>

<%= link_to 'New Item', new_admin_item_path %>

index.html.erb_spec.rb

require 'spec_helper'

describe "spree/admin/items/index" do

  before(:each) do
    assign(:items, [
      stub_model(Spree::Item,
        :name => "Name",
        :description => "Description"
      ),
      stub_model(Spree::Item,
        :name => "Name",
        :description => "Description"
      )
    ])
  end

  it "renders a list of spree/admin/items" do
    render
    # Run the generator again with the --webrat flag if you want to use webrat matchers
    assert_select "tr>td", :text => "Name".to_s, :count => 2
    assert_select "tr>td", :text => "Description".to_s, :count => 2
  end
end

PATHS

app/views/spree/admin/items/index.html.erb
config/routes.rb

spec/views/spree/admin/items/index.html.erb_spec.rb
spec/spec_helper.rb

routes.rb

Spree::Core::Engine.routes.draw do
  namespace :admin do
    resources :items
  end
end

spec_helper.rb

# Run Coverage report
require 'simplecov'
SimpleCov.start do
  add_filter 'spec/dummy'
  add_group 'Controllers', 'app/controllers'
  add_group 'Helpers', 'app/helpers'
  add_group 'Mailers', 'app/mailers'
  add_group 'Models', 'app/models'
  add_group 'Views', 'app/views'
  add_group 'Libraries', 'lib'
end

# Configure Rails Environment
ENV['RAILS_ENV'] = 'test'

require File.expand_path('../dummy/config/environment.rb',  __FILE__)

require 'rspec/rails'
require 'database_cleaner'
require 'ffaker'

# Requires supporting ruby files with custom matchers and macros, etc,
# in spec/support/ and its subdirectories.
Dir[File.join(File.dirname(__FILE__), 'support/**/*.rb')].each { |f| require f }

# Requires factories defined in spree_core
require 'spree/testing_support/factories'
require 'spree/testing_support/controller_requests'
require 'spree/testing_support/authorization_helpers'
require 'spree/testing_support/url_helpers'

# Requires factories defined in lib/spree_marketing_featured_items/factories.rb
require 'spree_marketing_featured_items/factories'

RSpec.configure do |config|
  config.include FactoryGirl::Syntax::Methods
  config.include Devise::TestHelpers, :type => :controller

  # == URL Helpers
  #
  # Allows access to Spree's routes in specs:
  #
  # visit spree.admin_path
  # current_path.should eql(spree.products_path)
  config.include Spree::TestingSupport::UrlHelpers
  config.include Spree::TestingSupport::ControllerRequests
  # == Mock Framework
  #
  # If you prefer to use mocha, flexmock or RR, uncomment the appropriate line:
  #
  # config.mock_with :mocha
  # config.mock_with :flexmock
  # config.mock_with :rr
  config.mock_with :rspec
  config.color = true

  # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
  config.fixture_path = "#{::Rails.root}/spec/fixtures"

  # Capybara javascript drivers require transactional fixtures set to false, and we use DatabaseCleaner
  # to cleanup after each test instead.  Without transactional fixtures set to false the records created
  # to setup a test will be unavailable to the browser, which runs under a seperate server instance.
  config.use_transactional_fixtures = false

  # Ensure Suite is set to use transactions for speed.
  config.before :suite do
    DatabaseCleaner.strategy = :transaction
    DatabaseCleaner.clean_with :truncation
  end

  # Before each spec check if it is a Javascript test and switch between using database transactions or not where necessary.
  config.before :each do
    DatabaseCleaner.strategy = example.metadata[:js] ? :truncation : :transaction
    DatabaseCleaner.start
  end

  # After each spec clean the database.
  config.after :each do
    DatabaseCleaner.clean
  end

  config.fail_fast = ENV['FAIL_FAST'] || false
end

This is the error

25. spree/admin/items/index renders a list of spree/admin/items
    Failure/Error: render
    ActionView::Template::Error:
    undefined method `admin_item_path' for #<#Class:0x007f94a0a98558:0x007f949f864760>

    ./app/views/spree/admin/items/index.html.erb:21:in`block in _03503b2d377e4ad82c488c69e41d0bb1'

    ./app/views/spree/admin/items/index.html.erb:16:in `each'

    ./app/views/spree/admin/items/index.html.erb:16:in`_03503b2d377e4ad82c488c69e41d0bb1'

    ./spec/views/spree/admin/items/index.html.erb_spec.rb:19:in `block (2 levels) in <top (required)>'

If I use spree.anything_path in views, all tests runs OK