diff --git a/test/test_ronn_document.rb b/test/test_ronn_document.rb
index 75788dc..a86793f 100644
--- a/test/test_ronn_document.rb
+++ b/test/test_ronn_document.rb
@@ -146,7 +146,7 @@ def canonicalize(text)
                      'toc'          => [['NAME', 'NAME']],
                      'organization' => nil,
                      'manual'       => nil
-                   }, YAML.load(@doc.to_yaml))
+                   }, YAML.load(@doc.to_yaml, permitted_classes: [Time]))
     end
 
     test 'converting to json' do