backport #8662, charset should not be appended for `head` responses

      1) Failure:
    test_head_created_with_image_png_content_type(RenderTest) [test/controller/render_test.rb:1238]:
    Expected: "image/png"
      Actual: "image/png; charset=utf-8"

1 files changed, 12 insertions, 1 deletions

diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index 8c631e218f..be5d25a436 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -503,6 +503,10 @@ class TestController < ActionController::Base
     head :created, :content_type => "application/json"
   end
 
+  def head_ok_with_image_png_content_type
+    head :ok, :content_type => "image/png"
+  end
+
   def head_with_location_header
     head :location => "/foo"
   end
@@ -1197,10 +1201,17 @@ class RenderTest < ActionController::TestCase
   def test_head_created_with_application_json_content_type
     post :head_created_with_application_json_content_type
     assert_blank @response.body
-    assert_equal "application/json", @response.content_type
+    assert_equal "application/json", @response.header["Content-Type"]
     assert_response :created
   end
 
+  def test_head_ok_with_image_png_content_type
+    post :head_ok_with_image_png_content_type
+    assert_blank @response.body
+    assert_equal "image/png", @response.header["Content-Type"]
+    assert_response :ok
+  end
+
   def test_head_with_location_header
     get :head_with_location_header
     assert_blank @response.body