1 files changed, 14 insertions, 0 deletions
diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index 17d834d55f..1ca668b9b1 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "abstract_unit"
 require "controller/fake_models"
 
@@ -604,6 +606,18 @@ class MetalRenderTest < ActionController::TestCase
   end
 end
 
+class ActionControllerRenderTest < ActionController::TestCase
+  class MinimalController < ActionController::Metal
+    include AbstractController::Rendering
+    include ActionController::Rendering
+  end
+
+  def test_direct_render_to_string_with_body
+    mc = MinimalController.new
+    assert_equal "Hello world!", mc.render_to_string(body: ["Hello world!"])
+  end
+end
+
 class ActionControllerBaseRenderTest < ActionController::TestCase
   def test_direct_render_to_string
     ac = ActionController::Base.new()