1 files changed, 6 insertions, 0 deletions
diff --git a/actionpack/test/controller/mime_type_test.rb b/actionpack/test/controller/mime_type_test.rb
index aa1d4459ee..436251b0f9 100644
--- a/actionpack/test/controller/mime_type_test.rb
+++ b/actionpack/test/controller/mime_type_test.rb
@@ -21,4 +21,10 @@ class MimeTypeTest < Test::Unit::TestCase
     expect = [Mime::HTML, Mime::XML, Mime::PNG, Mime::PLAIN, Mime::YAML, Mime::ALL]
     assert_equal expect, Mime::Type.parse(accept)
   end
+  
+  def test_custom_type
+    Mime::Type.register("image/gif", :gif)
+    assert_nothing_raised { Mime::GIF }
+    Mime.send :remove_const, :GIF
+  end
 end
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