3 files changed, 9 insertions, 15 deletions
diff --git a/actionpack/lib/action_dispatch/testing/assertions/dom.rb b/actionpack/lib/action_dispatch/testing/assertions/dom.rb
index 8f90a1223e..241a39393a 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/dom.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/dom.rb
@@ -7,20 +7,20 @@ module ActionDispatch
       #
       #   # assert that the referenced method generates the appropriate HTML string
       #   assert_dom_equal '<a href="http://www.example.com">Apples</a>', link_to("Apples", "http://www.example.com")
-      def assert_dom_equal(expected, actual, message = "")
+      def assert_dom_equal(expected, actual, message = nil)
         expected_dom = HTML::Document.new(expected).root
         actual_dom   = HTML::Document.new(actual).root
-        assert_equal expected_dom, actual_dom
+        assert_equal expected_dom, actual_dom, message
       end
 
       # The negated form of +assert_dom_equivalent+.
       #
       #   # assert that the referenced method does not generate the specified HTML string
       #   assert_dom_not_equal '<a href="http://www.example.com">Apples</a>', link_to("Oranges", "http://www.example.com")
-      def assert_dom_not_equal(expected, actual, message = "")
+      def assert_dom_not_equal(expected, actual, message = nil)
         expected_dom = HTML::Document.new(expected).root
         actual_dom   = HTML::Document.new(actual).root
-        assert_not_equal expected_dom, actual_dom
+        assert_not_equal expected_dom, actual_dom, message
       end
     end
   end
diff --git a/actionpack/lib/action_dispatch/testing/integration.rb b/actionpack/lib/action_dispatch/testing/integration.rb
index 1f899a434c..9beb30307b 100644
--- a/actionpack/lib/action_dispatch/testing/integration.rb
+++ b/actionpack/lib/action_dispatch/testing/integration.rb
@@ -298,8 +298,6 @@ module ActionDispatch
 
           session = Rack::Test::Session.new(_mock_session)
 
-          env.merge!(env)
-
           # NOTE: rack-test v0.5 doesn't build a default uri correctly
           # Make sure requested path is always a full uri
           uri = URI.parse('/')
@@ -489,10 +487,6 @@ module ActionDispatch
     @@app = nil
 
     def self.app
-      if !@@app && !ActionDispatch.test_app
-        ActiveSupport::Deprecation.warn "Rails application fallback is deprecated and no longer works, please set ActionDispatch.test_app"
-      end
-
       @@app || ActionDispatch.test_app
     end
 
diff --git a/actionpack/lib/action_dispatch/testing/test_request.rb b/actionpack/lib/action_dispatch/testing/test_request.rb
index c63778f870..57c678843b 100644
--- a/actionpack/lib/action_dispatch/testing/test_request.rb
+++ b/actionpack/lib/action_dispatch/testing/test_request.rb
@@ -3,7 +3,11 @@ require 'rack/utils'
 
 module ActionDispatch
   class TestRequest < Request
-    DEFAULT_ENV = Rack::MockRequest.env_for('/')
+    DEFAULT_ENV = Rack::MockRequest.env_for('/',
+      'HTTP_HOST'       => 'test.host',
+      'REMOTE_ADDR'     => '0.0.0.0',
+      'HTTP_USER_AGENT' => 'Rails Testing'
+    )
 
     def self.new(env = {})
       super
@@ -12,10 +16,6 @@ module ActionDispatch
     def initialize(env = {})
       env = Rails.application.env_config.merge(env) if defined?(Rails.application) && Rails.application
       super(default_env.merge(env))
-
-      self.host        = 'test.host'
-      self.remote_addr = '0.0.0.0'
-      self.user_agent  = 'Rails Testing'
     end
 
     def request_method=(method)