Remove content-length as well

actionpack/lib/action_controller/metal/head.rb

@@ -28,10 +28,11 @@ module ActionController
       self.status = status
       self.location = url_for(location) if location
 
-      if include_content_type?(self.status)
+      if include_content_headers?(self.status)
         self.content_type = Mime[formats.first] if formats
       else
         headers.delete('Content-Type')
+        headers.delete('Content-Length')
       end
 
       self.response_body = " "
@@ -39,7 +40,7 @@ module ActionController
 
     private
     # :nodoc:
-    def include_content_type?(status)
+    def include_content_headers?(status)
       case status
       when 100..199
         false

actionpack/test/controller/new_base/bare_metal_test.rb

@@ -78,31 +78,37 @@ module BareMetalTest
     test "head :continue (100) does not return a content-type header" do
       headers = HeadController.action(:continue).call(Rack::MockRequest.env_for("/")).second
       assert_nil headers['Content-Type']
+      assert_nil headers['Content-Length']
     end
 
     test "head :continue (101) does not return a content-type header" do
       headers = HeadController.action(:continue).call(Rack::MockRequest.env_for("/")).second
       assert_nil headers['Content-Type']
+      assert_nil headers['Content-Length']
     end
 
     test "head :processing (102) does not return a content-type header" do
       headers = HeadController.action(:processing).call(Rack::MockRequest.env_for("/")).second
       assert_nil headers['Content-Type']
+      assert_nil headers['Content-Length']
     end
 
     test "head :no_content (204) does not return a content-type header" do
       headers = HeadController.action(:no_content).call(Rack::MockRequest.env_for("/")).second
       assert_nil headers['Content-Type']
+      assert_nil headers['Content-Length']
     end
 
     test "head :reset_content (205) does not return a content-type header" do
       headers = HeadController.action(:reset_content).call(Rack::MockRequest.env_for("/")).second
       assert_nil headers['Content-Type']
+      assert_nil headers['Content-Length']
     end
 
     test "head :not_modified (304) does not return a content-type header" do
       headers = HeadController.action(:not_modified).call(Rack::MockRequest.env_for("/")).second
       assert_nil headers['Content-Type']
+      assert_nil headers['Content-Length']
     end
   end