2 files changed, 35 insertions, 9 deletions

diff --git a/actionpack/test/controller/routing_test.rb b/actionpack/test/controller/routing_test.rb
index fefb84e095..f09051b306 100644
--- a/actionpack/test/controller/routing_test.rb
+++ b/actionpack/test/controller/routing_test.rb
@@ -96,6 +96,22 @@ class LegacyRouteSetTests < ActiveSupport::TestCase
     assert_equal({ "artist" => "journey", "song" => "faithfully" }, hash)
   end
 
+  def test_id_encoding
+    rs.draw do
+      get "/journey/:id", to: lambda { |env|
+        param = ActionDispatch::Request.new(env).path_parameters
+        resp = ActiveSupport::JSON.encode param
+        [200, {}, [resp]]
+      }
+    end
+
+    # The encoding of the URL in production is *binary*, so we add a
+    # .b here.
+    hash = ActiveSupport::JSON.decode get(URI("http://example.org/journey/%E5%A4%AA%E9%83%8E".b))
+    assert_equal({ "id" => "太郎" }, hash)
+    assert_equal ::Encoding::UTF_8, hash["id"].encoding
+  end
+
   def test_id_with_dash
     rs.draw do
       get "/journey/:id", to: lambda { |env|
diff --git a/actionpack/test/dispatch/routing_test.rb b/actionpack/test/dispatch/routing_test.rb
index 1af0edc1d3..446b65a9b9 100644
--- a/actionpack/test/dispatch/routing_test.rb
+++ b/actionpack/test/dispatch/routing_test.rb
@@ -4416,39 +4416,49 @@ end
 
 class TestInvalidUrls < ActionDispatch::IntegrationTest
   class FooController < ActionController::Base
+    def self.binary_params_for?(action)
+      action == "show"
+    end
+
     def show
       render plain: "foo#show"
     end
   end
 
-  test "invalid UTF-8 encoding is treated as ASCII 8BIT encode" do
+  test "invalid UTF-8 encoding returns a bad request" do
     with_routing do |set|
       set.draw do
         get "/bar/:id", to: redirect("/foo/show/%{id}")
-        get "/foo/show(/:id)", to: "test_invalid_urls/foo#show"
 
         ok = lambda { |env| [200, { "Content-Type" => "text/plain" }, []] }
         get "/foobar/:id", to: ok
 
         ActiveSupport::Deprecation.silence do
-          get "/foo(/:action(/:id))", controller: "test_invalid_urls/foo"
           get "/:controller(/:action(/:id))"
         end
       end
 
       get "/%E2%EF%BF%BD%A6"
-      assert_response :not_found
+      assert_response :bad_request
 
       get "/foo/%E2%EF%BF%BD%A6"
-      assert_response :not_found
-
-      get "/foo/show/%E2%EF%BF%BD%A6"
-      assert_response :ok
+      assert_response :bad_request
 
       get "/bar/%E2%EF%BF%BD%A6"
-      assert_response :redirect
+      assert_response :bad_request
 
       get "/foobar/%E2%EF%BF%BD%A6"
+      assert_response :bad_request
+    end
+  end
+
+  test "params encoded with binary_params_for? are treated as ASCII 8bit" do
+    with_routing do |set|
+      set.draw do
+        get "/foo/show(/:id)", to: "test_invalid_urls/foo#show"
+      end
+
+      get "/foo/show/%E2%EF%BF%BD%A6"
       assert_response :ok
     end
   end