Correctly use the response's status code calling head

Commit 20fece1 introduced the `_status_code` method to fix calls to
`head :ok`. This method has been added on both ActionController::Metal
and ActionDispatch::Response.

As for the latter, this method is just equivalent to the `response_code`
one so commit aefec3c removed it from the `Reponse` object so call to
the `_status_code` method on an ActionController::Base instance would be
handled by the `Metal` class (which `Base` inherits from) but the status
code is not updated according to the response at this level.

The fix is to actually rely on `response_code` for ActionController::Base
instances but this method doesn't exist for bare Metal controllers so we
need to define it.

4 files changed, 23 insertions, 5 deletions

diff --git a/actionpack/CHANGELOG.md b/actionpack/CHANGELOG.md
index b5380a46e8..3f29d810d5 100644
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
@@ -1,3 +1,7 @@
+*   Correctly rely on the response's status code to handle calls to `head`.
+
+    *Robin Dupret*
+
 *   Using `head` method returns empty response_body instead
     of returning a single space " ".
 
diff --git a/actionpack/lib/action_controller/metal.rb b/actionpack/lib/action_controller/metal.rb
index 6dd213b2f7..993f8e150d 100644
--- a/actionpack/lib/action_controller/metal.rb
+++ b/actionpack/lib/action_controller/metal.rb
@@ -173,6 +173,7 @@ module ActionController
     def status
       @_status
     end
+    alias :response_code :status # :nodoc:
 
     def status=(status)
       @_status = Rack::Utils.status_code(status)
@@ -236,9 +237,5 @@ module ActionController
         lambda { |env| new.dispatch(name, klass.new(env)) }
       end
     end
-
-    def _status_code #:nodoc:
-      @_status
-    end
   end
 end
diff --git a/actionpack/lib/action_controller/metal/head.rb b/actionpack/lib/action_controller/metal/head.rb
index 57e60222cd..0d93e2f7aa 100644
--- a/actionpack/lib/action_controller/metal/head.rb
+++ b/actionpack/lib/action_controller/metal/head.rb
@@ -31,7 +31,7 @@ module ActionController
 
       self.response_body = ""
 
-      if include_content?(self._status_code)
+      if include_content?(self.response_code)
         self.content_type = content_type || (Mime[formats.first] if formats)
         self.response.charset = false if self.response
       else
diff --git a/actionpack/test/controller/render_test.rb b/actionpack/test/controller/render_test.rb
index b036b6c08e..929b161eb6 100644
--- a/actionpack/test/controller/render_test.rb
+++ b/actionpack/test/controller/render_test.rb
@@ -217,6 +217,15 @@ class TestController < ActionController::Base
     head :forbidden, :x_custom_header => "something"
   end
 
+  def head_with_no_content
+    # Fill in the headers with dummy data to make
+    # sure they get removed during the testing
+    response.headers["Content-Type"] = "dummy"
+    response.headers["Content-Length"] = 42
+
+    head 204
+  end
+
   private
 
     def set_variable_for_layout
@@ -545,6 +554,14 @@ class HeadRenderTest < ActionController::TestCase
     end
   end
 
+  def test_head_with_no_content
+    get :head_with_no_content
+
+    assert_equal 204, @response.status
+    assert_nil @response.headers["Content-Type"]
+    assert_nil @response.headers["Content-Length"]
+  end
+
   def test_head_with_string_status
     get :head_with_string_status, :status => "404 Eat Dirt"
     assert_equal 404, @response.response_code