Add redirection path in the error message of assert_response if response is :redirect

- If the assert_response is checking for any non-redirect response like
  :success and actual response is :redirect then, the error message displayed
  was -

     Expected response to be a <success>, but was <302>

- This commit adds the redirect path to the error message of
  assert_response if the response is :redirect.
  So above message is changed to -

     Expected response to be a <success>, but was a redirect to <http://test.host/posts/lol>

2 files changed, 31 insertions, 1 deletions

diff --git a/actionpack/lib/action_dispatch/testing/assertions/response.rb b/actionpack/lib/action_dispatch/testing/assertions/response.rb
index eab20b075d..5af052afb4 100644
--- a/actionpack/lib/action_dispatch/testing/assertions/response.rb
+++ b/actionpack/lib/action_dispatch/testing/assertions/response.rb
@@ -27,6 +27,8 @@ module ActionDispatch
       #   # Asserts that the response code was status code 401 (unauthorized)
       #   assert_response 401
       def assert_response(type, message = nil)
+        message ||= generate_response_message(type)
+
         if Symbol === type
           if [:success, :missing, :redirect, :error].include?(type)
             assert_predicate @response, RESPONSE_PREDICATES[type], message
@@ -82,6 +84,19 @@ module ActionDispatch
             handle._compute_redirect_to_location(@request, fragment)
           end
         end
+
+        def generate_response_message(type)
+          message = "Expected response to be a <#{type}>, but was"
+
+          if @response.redirection?
+            redirect_is = normalize_argument_to_redirection(@response.location)
+            message << " a redirect to <#{redirect_is}>"
+          else
+            message << " <#{@response.response_code}>"
+          end
+
+          message
+        end
     end
   end
 end
diff --git a/actionpack/test/assertions/response_assertions_test.rb b/actionpack/test/assertions/response_assertions_test.rb
index 82c747680d..6c7036aa1a 100644
--- a/actionpack/test/assertions/response_assertions_test.rb
+++ b/actionpack/test/assertions/response_assertions_test.rb
@@ -6,7 +6,12 @@ module ActionDispatch
     class ResponseAssertionsTest < ActiveSupport::TestCase
       include ResponseAssertions
 
-      FakeResponse = Struct.new(:response_code) do
+      FakeResponse = Struct.new(:response_code, :location) do
+        def initialize(*)
+          super
+          self.location ||= "http://test.example.com/posts"
+        end
+
         [:successful, :not_found, :redirection, :server_error].each do |sym|
           define_method("#{sym}?") do
             sym == response_code
@@ -58,6 +63,16 @@ module ActionDispatch
           assert_response :succezz
         }
       end
+
+      def test_message_when_response_is_redirect_but_asserted_for_status_other_than_redirect
+        @response = FakeResponse.new :redirection, "http://test.host/posts/redirect/1"
+        error = assert_raises(Minitest::Assertion) do
+          assert_response :success
+        end
+
+        expected = "Expected response to be a <success>, but was a redirect to <http://test.host/posts/redirect/1>."
+        assert_match expected, error.message
+      end
     end
   end
 end