Make `parsed_body` extract parser from the content type.

We're not guaranteed to have a `RequestEncoder` to assign on `get` requests
because we aren't extracting the parser from the response content type.

Until now.

1 files changed, 10 insertions, 0 deletions

diff --git a/actionpack/test/controller/integration_test.rb b/actionpack/test/controller/integration_test.rb
index cb524bacb2..ea50f05f4d 100644
--- a/actionpack/test/controller/integration_test.rb
+++ b/actionpack/test/controller/integration_test.rb
@@ -1171,6 +1171,16 @@ class IntegrationRequestEncodersTest < ActionDispatch::IntegrationTest
     Mime::Type.unregister :wibble
   end
 
+  def test_parsed_body_without_as_option
+    with_routing do |routes|
+      routes.draw { get ':action' => FooController }
+
+      get '/foos_json.json', params: { foo: 'heyo' }
+
+      assert_equal({ 'foo' => 'heyo' }, response.parsed_body)
+    end
+  end
+
   private
     def post_to_foos(as:)
       with_routing do |routes|