运行’bundle exec rspec spec /’后,我收到以下错误：

1) Authentication authorization as wrong user submitting a PATCH request to the Users#update action 
     Failure/Error: specify { expect(response).to redirect_to(root_url) }
     ArgumentError:
       Missing host to link to! Please provide the :host parameter,set default_url_options[:host],or set :only_path to true
     # ./spec/features/authentication_pages_spec.rb:79:in `block (5 levels) in <top (required)>'

我的验证测试代码是：

需要’spec_helper’

describe "Authentication",type: :request do

  subject { page }


  describe "signin page" do
    before { visit signin_path }

    it { should have_content('Sign in') }
    it { should have_title('Sign in') }
  end

  describe "signin" do
    before { visit signin_path }

    describe "with invalid information" do
      before { click_button "Sign in" }

      it { should have_title('Sign in') }
      it { should have_selector('div.alert.alert-error',text: 'Invalid') }

      describe "after visiting another page" do
        before { click_link "Home" }
        it { should_not have_selector('div.alert.alert-error') }
      end

    end

    describe "with valid information" do
      let(:user) { FactoryGirl.create(:user) }
      before { sign_in user }

      #it { should have_title(user.name) }
      it { should have_link('Profile',href: user_path(user)) }
      it { should have_link('Settings',href: edit_user_path(user)) }
      it { should have_link('Sign out',href: signout_path) }
      it { should_not have_link('Sign in',href: signin_path) }

      describe "followed by signout" do
        before { click_link "Sign out" }
        it { should have_link('Sign in') }
      end
    end
  end

  describe "authorization" do

    describe "for non-signed-in users" do
      let(:user) { FactoryGirl.create(:user) }

      describe "in the Users controller" do

        describe "visiting the edit page" do
          before { visit edit_user_path(user) }
          it { should have_title('Sign in') }
        end

        describe "submitting to the update action" do
          before { patch user_path(user) }
          specify { expect(response).to redirect_to(signin_path) }
        end
      end
    end

    describe "as wrong user" do
      let(:user) { FactoryGirl.create(:user) }
      let(:wrong_user) { FactoryGirl.create(:user,email: "wrong@example.com") }
      before { sign_in user,no_capybara: true }

      describe "visiting Users#edit page" do
        before { visit edit_user_path(wrong_user) }
        #it { should_not have_title(full_title('Edit user')) }
      end

      describe "submitting a PATCH request to the Users#update action" do
        before { patch user_path(wrong_user) }
        specify { expect(response).to redirect_to(root_url) }
      end
    end

  end
end

我不知道如何解决这个问题,所以测试通过.我该如何解决？有人可以解释出了什么问题吗？ (根据教程测试应该通过).