2 files changed, 12 insertions, 4 deletions
diff --git a/actionpack/test/dispatch/response_test.rb b/actionpack/test/dispatch/response_test.rb
index c61423dce4..5fbd19acdf 100644
--- a/actionpack/test/dispatch/response_test.rb
+++ b/actionpack/test/dispatch/response_test.rb
@@ -254,10 +254,6 @@ class ResponseTest < ActiveSupport::TestCase
 end
 
 class ResponseIntegrationTest < ActionDispatch::IntegrationTest
-  def app
-    @app
-  end
-
   test "response cache control from railsish app" do
     @app = lambda { |env|
       ActionDispatch::Response.new.tap { |resp|
diff --git a/actionpack/test/dispatch/routing_test.rb b/actionpack/test/dispatch/routing_test.rb
index 3a95a9025f..ca5de05814 100644
--- a/actionpack/test/dispatch/routing_test.rb
+++ b/actionpack/test/dispatch/routing_test.rb
@@ -3477,6 +3477,18 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     assert_equal '/post/comments/new', new_comment_path
   end
 
+  def test_head_fetch_with_mount_on_root
+    draw do
+      get '/home' => 'test#index'
+      mount lambda { |env| [404, {"Content-Type" => "text/html"}, ["testing"]] }, at: '/'
+    end
+    head '/home'
+    assert_response :success
+
+    head '/'
+    assert_response :not_found
+  end
+
 private
 
   def draw(&block)