Use _url routes instead of _path

lib/devise/failure_app.rb

@@ -96,15 +96,15 @@ module Devise
           request.referrer
         end
 
-        path || scope_path
+        path || scope_url
       else
-        scope_path
+        scope_url
       end
     end
 
-    def scope_path
+    def scope_url
       opts  = {}
-      route = :"new_#{scope}_session_path"
+      route = :"new_#{scope}_session_url"
       opts[:format] = request_format unless skip_format?
 
       config = Rails.application.config
@@ -114,8 +114,8 @@ module Devise
 
       if context.respond_to?(route)
         context.send(route, opts)
-      elsif respond_to?(:root_path)
-        root_path(opts)
+      elsif respond_to?(:root_url)
+        root_url(opts)
       else
         "/"
       end

test/failure_app_test.rb

@@ -8,6 +8,16 @@ class FailureTest < ActiveSupport::TestCase
     end
   end
 
+  class FailureWithSubdomain < RootFailureApp
+    routes = ActionDispatch::Routing::RouteSet.new
+
+    routes.draw do
+      root to: 'foo#bar', constraints: { subdomain: 'sub' }
+    end
+
+    include routes.url_helpers
+  end
+
   class FailureWithI18nOptions < Devise::FailureApp
     def i18n_options(options)
       options.merge(name: 'Steve')
@@ -42,6 +52,13 @@ class FailureTest < ActiveSupport::TestCase
       assert_equal 'http://test.host/users/sign_in', @response.second['Location']
     end
 
+    test 'returns to the default redirect location considering subdomain' do
+      call_failure('warden.options' => { scope: :subdomain_user })
+      assert_equal 302, @response.first
+      assert_equal 'You need to sign in or sign up before continuing.', @request.flash[:alert]
+      assert_equal 'http://sub.test.host/subdomain_users/sign_in', @response.second['Location']
+    end
+
     test 'returns to the default redirect location for wildcard requests' do
       call_failure 'action_dispatch.request.formats' => nil, 'HTTP_ACCEPT' => '*/*'
       assert_equal 302, @response.first
@@ -57,6 +74,15 @@ class FailureTest < ActiveSupport::TestCase
       end
     end
 
+    test 'returns to the root path considering subdomain if no session path is available' do
+      swap Devise, router_name: :fake_app do
+        call_failure app: FailureWithSubdomain
+        assert_equal 302, @response.first
+        assert_equal 'You need to sign in or sign up before continuing.', @request.flash[:alert]
+        assert_equal 'http://sub.test.host/', @response.second['Location']
+      end
+    end
+
     if Rails.application.config.respond_to?(:relative_url_root)
       test 'returns to the default redirect location considering the relative url root' do
         swap Rails.application.config, relative_url_root: "/sample" do
@@ -65,6 +91,14 @@ class FailureTest < ActiveSupport::TestCase
           assert_equal 'http://test.host/sample/users/sign_in', @response.second['Location']
         end
       end
+
+      test 'returns to the default redirect location considering the relative url root and subdomain' do
+        swap Rails.application.config, relative_url_root: "/sample" do
+          call_failure('warden.options' => { scope: :subdomain_user })
+          assert_equal 302, @response.first
+          assert_equal 'http://sub.test.host/sample/subdomain_users/sign_in', @response.second['Location']
+        end
+      end
     end
 
     test 'uses the proxy failure message as symbol' do

test/rails_app/config/routes.rb

@@ -66,6 +66,10 @@ Rails.application.routes.draw do
     devise_for :homebase_admin, class_name: "Admin", path: "homebase"
   end
 
+  constraints(subdomain: 'sub') do
+    devise_for :subdomain_users, class_name: "User", only: [:sessions]
+  end
+
   devise_for :skip_admin, class_name: "Admin", skip: :all
 
   # Routes for format=false testing