[ruby/rubygems] Skip test when Psych unsafe_load is used

ruby/rubygems@2636b4d24a

Author: hsbt

test/rubygems/test_gem_commands_owner_command.rb

@@ -55,7 +55,11 @@ def test_show_owners
   end
 
   def test_show_owners_dont_load_objects
-    pend "testing a psych-only API" unless defined?(::Psych::DisallowedClass)
+    Gem.load_yaml
+
+    # Gem::SafeYAML.load uses Psych.unsafe_load when Psych is enabled,
+    # which does not restrict classes. Only YAMLSerializer restricts object tags.
+    pend "Gem::SafeYAML.load uses Psych.unsafe_load which does not restrict classes" if Gem.use_psych?
 
     response = <<EOF
 ---