Test for r18158 (#22481).

Patch by Go MAEDA.


git-svn-id: http://svn.redmine.org/redmine/trunk@18159 e93f8b46-1217-0410-a6f0-8f06a7374b81

test/functional/attachments_controller_test.rb

@@ -404,6 +404,16 @@ class AttachmentsControllerTest < Redmine::ControllerTest
       assert_response 304
     end
 
+    def test_thumbnail_for_pdf_should_be_png
+      Attachment.clear_thumbnails
+      @request.session[:user_id] = 2
+      get :thumbnail, :params => {
+          :id => 23   # ecookbook-gantt.pdf
+        }
+      assert_response :success
+      assert_equal 'image/png', response.content_type
+    end
+
     def test_thumbnail_should_not_exceed_maximum_size
       Redmine::Thumbnail.expects(:generate).with {|source, target, size| size == 800}